mirrored file at http://SaturnianCosmology.Org/ For complete access to all the files of this collection see http://SaturnianCosmology.org/search.php ========================================================== ITRDB Forum FAQ Version 98.1 Last Modified Dec 1998 _________________________________________________________________ The International Tree Ring Data Bank Forum Frequently Asked Questions a.k.a. THE TREE RING FAQ Current FAQ Editors: R.Argent at civag.unimelb.edu.au http://www.civag.unimelb.edu.au/~argent/ rjwilson at julian.uwo.ca Page Access Counter (Since 3 August, 2000) _________________________________________________________________ Welcome to the Tree Ring FAQ. Below you will find the list of Frequently Asked Questions (FAQ's) that are currently answered in the FAQ. Note that the questions are all listed as "Qx.x:", so the quickest way to find the answer you are after (if you are reading this in electronic form) is to search for the string "Qx.x:". Ideas for layout , themes, approaches and even content for this FAQ were stolen from: Heitkoetter, Joerg and Beasley, David, eds. (1994) "The Hitch-Hiker's Guide to Evolutionary Computation: A list of Frequently Asked Questions (FAQ)", USENET: comp.ai.genetic. Available via anonymous FTP from rtfm.mit.edu:/pub/usenet/news.answers/ai-faq/genetic/ About 90 pages. and The on-line hacker Jargon File, Version 3.2.0, Mar 15 1995: Spring (That's northern hemisphere spring, naturally!) 1995 update. Latest version available via anon. ftp at ftp.gnu.ai.mit.edu:/pub/gnu/ 23822 lines, 185961 words, 1226358 characters, and 2031 entries. Disclaimer: We cannot hope to answer all the questions and problems of the tree-ring community, but our hope is that this will be at least a good start. If your answer is not here then why not present your problem to the Forum. This FAQ is not a "Teach yourself Tree-Rings in 2 hours", but rather an aid to the "Bigger Picture". Acknowledgement: Page Counter supplied by http://www.digits.com/ _________________________________________________________________ CONTENTS 0. FAQ Introduction Q0.1: What is a FAQ? Q0.2: What is this FAQ? Q0.3: What is netiquette? Q0.4: Where have the answers to these questions come from? Q0.5: How accurate are the answers? 1. Background Q1.1: What is the ITRDB? Q1.2: Where can I find tree-ring chronologies? Q1.3: Contribution of new data? Q1.3.1: What information should I include with tree-ring contributions? Q1.3.2: What are the minimum requirements for tree-ring data? Q1.3.3: How do I contribute my tree-ring data? Q1.4: and the Tree Ring Society? 2. The Forum Q2.1: And how about this email forum, the ITRDB Forum? Q2.2: How do I subscribe/ unsubscribe/ stop my mail while I'm away? Q2.3: Why shouldn't I just use the "Reply" function? (why shouldn't I ask Henri this question?) 3. Dendro Basics Q3.1: What is Dendrochronology? Q3.2: Subfields of Dendrochronolgy? Q3.3: What is crossdating? Q3.4: Why is crossdating so important? Q3.5: Methods of crossdating? Q3.6: Principles of Dendrochronology? Q3.6.1: Basic Definitions? Q3.6.2: Basic Principles? 4. Dendro Information Q4.1. What are the standard texts in the fields? Q4.2: key papers? Q4.3: journals? Q4.4: WWW Home Pages? Q4.5: Other electronic sources? Q4.6: How do I translate Feuerwunde and Zellwandwachstum? Q4.7: Where do I find the dendro bibliography? Q4.8: The European Catalogue of Tree-Ring Chronologies. Q4.8.1: Background Q4.8.2: Objectives of the Catalogue Q4.8.3: Participants Q4.8.4: Information listed in the Catalogue Q4.8.5: Collecting and Displaying the information Q4.8.6: The Future of the Catalogue 5. Software Q5.1: What software is available? Q5.2: What's the ITRDB Program Library? Q5.2.1: the DPL? Q5.2.2: Arstan? Q5.2.3: Cofecha? Q5.3: European software packages? Q5.4: Other tree-ring related software? Q5.4.1: ITRDB Display Software and PaleoVu? Q5.4.2: Precon 5.01? Q5.4.3: WinDENDRO? Q5.4.4: TREERING 3.0? Q5.4.5: FHX2? Q5.4.6: Free Palaeoclimatic Software? Q5.4.7: DendroScan? 6. Data Formats Q6.1: What are all the different data formats? Q6.2: Which should I use? Q6.3: Can I convert between them? 7. Equipment Q7.1: What equipment do I need to become a dendro? Q7.2: How do I tell a good corer from an average one? Q7.3: Where do I get a good corer? Q7.4: straws? Q7.5: a measuring system? Q7.6: other equipment? 8. Field Work Q8.1: How do I use a corer (safely)? Q8.2: A chainsaw? Q8.3: I've stuck my corer in a tree - how do I get it out? Q8.4: Does coring damage trees much? 9. Sample Preparation Q9.1: How do I safely transport and preserve samples? Q9.2: Sample/surface preparation? Q9.3: What should I use to enhance the surface? Q9.4: How do I get resin off my cores? Q9.5: Twisted cores? 10. More Information Q10.1: Where can I find out more? 50. Glossary Q50.0: Do you have a glossary of tree ring terms? _________________________________________________________________ ANSWERS ---------------------------- 0. FAQ Introduction Q0.1: What is a FAQ? {top} FAQ /F-A-Q/ or /fak/ [USENET] n. 1. A Frequently Asked Question. 2. A compendium of accumulated lore, posted periodically to high-volume newsgroups in an attempt to forestall such questions. Some people prefer the term `FAQ list' or `FAQL' /fa'kl/, reserving `FAQ' for sense 1. RTFAQ /R-T-F-A-Q/ [USENET: primarily written] imp. Abbrev. for `Read the FAQ!', an exhortation that the person addressed ought to read the newsgroup's FAQ list before posting questions. To put it simply, a FAQ is a list of Frequently Asked Questions about a subject and normally answers are even provided. Q0.2: What is this FAQ? {top} This FAQ is the FAQ of the International Tree Ring Data Bank Forum (ITRDB forum). There are presently two versions of this FAQ. The Internet version that can be found at: http://aqua.civag.unimelb.edu.au/~argent/treering/treefaq.html or the Windows Help me file version that can be downloaded from: ftp://ftp.geog.uwo.ca/rob/treefaq/ Q0.3: What is netiquette? {top} Netiquette /net'ee-ket/ or /net'i-ket/ n. [portmanteau from "network etiquette"] The conventions of politeness recognized on usenet, such as avoidance of cross-posting to inappropriate groups, limiting of a signature (.sig) file to five lines and refraining from commercial pluggery. Although usenet is usually characterized as "an anarchy, with no laws and no one in charge" there have "emerged" several rules over the past years that facilitate life within newsgroups and mail lists. The rules concerning message subjects and subject lines are of particular interest, as follow: 1. Requests Requests are articles of the form "I am looking for X" where X is something public like a book, an article, a piece of software. If multiple different answers can be expected, the person making the request should prepare to make a summary of the answers he/she got and announce to do so with a phrase like "Please e-mail, I'll summarize" at the end of the posting. The Subject line of the posting should then be something like "Request: X" 2. Questions As opposed to requests, questions are concerned with something so specific that general interest cannot readily be assumed. If the poster thinks that the topic is of some general interest, he/she should announce a summary (see above). The Subject line of the posting should be something like "Question: this-and-that" (Q: this-and-that) or have the form of a question (i.e., end with a question mark) 3. Answers These are reactions to questions or requests. As a rule of thumb articles of type "answer" should be rare. Ideally, in most cases either the answer is too specific to be of general interest (and should thus be e-mailed to the poster) or a summary was announced with the question or request (and answers should thus be e-mailed to the poster). The subject lines of answers are automatically adjusted by the news software. 4. Summaries In all cases of requests or questions the answers for which can be assumed to be of some general interest, the poster of the request or question shall summarize the answers he/she received. Such a summary should be announced in the original posting of the question or request with a phrase like "Please answer by e-mail, I'll summarize" In such a case answers should NOT be posted to the newsgroup but instead be mailed to the poster who collects and reviews them. After about 10 to 20 days from the original posting, its poster should make the summary of answers and post it to the net. Some care should be invested into a summary: a) simple concatenation of all the answers might not be enough; instead redundancies, irrelevancies, verbosities and errors should be filtered out (as good as possible), b) the answers shall be separated clearly c) the contributors of the individual answers shall be identifiable unless they requested to remain anonymous d) the summary shall start with the "quintessence" of the answers, as seen by the original poster e) A summary should, when posted, clearly be indicated to be one by giving it a Subject line starting with "Summary:" Note that a good summary is pure gold for the rest of the newsgroup community, so summary work will be most appreciated by all of us. (Good summaries are more valuable than any moderator!) 5. Announcements Some articles never need any public reaction. These are called announcements (for instance for a workshop, conference or the availability of some technical report or software system). Announcements should be clearly indicated to be such by giving them a subject line of the form "Announcement: this-and-that", or just "A: this-and-that". Due to common practice, conference announcements usually carry a "CFP:" in their subject line, i.e. "call for papers" (or: "call for participation"). 6. Reports Sometimes people spontaneously want to report something to the newsgroup. This might be special experiences with some software, results of own experiments or conceptual work, or especially interesting information from somewhere else. Reports should be clearly indicated to be such by giving them a subject line of the form "Report: this-and-that" 7. Discussions An especially valuable possibility of USENET is of course that of discussing a certain topic with hundreds of potential participants. All traffic in the newsgroup that can not be subsumed under one of the above categories should belong to a discussion. If somebody explicitly wants to start a discussion, he/she can do so by giving the posting a subject line of the form "Start discussion: this-and-that" (People who react on this, please remove the "Start discussion: " label from the subject line of your replies) Q0.4: Where have the answers to these questions come from? {top} Rob and Rob's fertile imagination and limited field, lab and forum-reading experience, along with contributions from Hal Fritts, Henri Grissino-Mayer, Michele Kaennel, Bob Keeland, Martin Munro, Fritz Schweingruber, Dave Yamaguchi, Ed Cook, Rupert Wimmer, Tom Levanic, Paul Krusic, Frank Rinn, Malcolm Hughes, Dave LeBlanc, Jacques Tardif, John Brown, Dave Lawrence, Richard Holmes, John Innes, Wayne Shepperd, Peter Kelly, Kevin Smith, Frank Telewski, Stephanie Wear, Rex Adams, Constantin Sander, Malcolm Cleaveland, Piyal Kariyawasam, Geoff Downes, William Wright, Elaine Kennedy Sutherland, Joy Young, Jim Parks, Neil Pederson, Russ Hutchinson, Yves Begin, Ian Campbell, Won-Kyu Park, Oriol Bosch, Bruce Bauer, Osamu Kobayashi, Jennifer Hillam, Fabian Meyer, Karriaunna Scotti and many others. THANK YOU ALL!! Q0.5: How accurate are the answers? {top} Good Question! Information supplied to the FAQ editors and to the ITRDB Forum is given freely by people with a wide range of field and lab experience in a HUGE range of dendro-related fields. The accumulated expertise probably runs to a couple of millennia, and with constant cross-fertilisation of ideas via papers, meetings, e-mail discussions and World Wide Web home pages the answers given here probably represent some of the best advice around. The caveat on this is, of course, "you get the quality that you pay for"! ---------------------------- 1. Background Q1.1: What is the ITRDB? {top} The International Tree-Ring Data Bank (ITRDB) is a professional organization providing the only central store-house for dendrochronological data from around the world. The ITRDB was formed in 1974 at a workshop of dendrochronologists and has been run exclusively as a "grass roots" organization. It was developed largely on a volunteer basis, with modest funding from the United States National Science Foundation, as a supplement to research support to Harold Fritts at the Laboratory of Tree-Ring Research, The University of Arizona. Its holdings include dated tree-ring width and density measurements and site chronologies with appropriate site information. These data can be used for all applications in dendrochronology, and are available to all researchers in all fields. The primary purpose for the ITRDB is to provide a permanent location for the storage of well-dated dendrochronological data from around the world. This protects data from loss when laboratories move or dissolve or when scientists move to other projects or retire. Membership in the ITRDB is automatic for those individuals and institutions that contribute dendrochronological data. It is more important to stress that the collective data is shared around the world when it is submitted to the ITRDB. For more information connect to the following web sites: http://web.utk.edu/~grissino/itrdb.htm http://www.ngdc.noaa.gov/paleo/treering.html Q1.2: Where can I find tree-ring chronologies? {top} Tree-ring chronologies held by the ITRDB are available from the National Geophysical Data Center (NGDC) via anonymous FTP or through the World Wide Web. Obtain the tree-ring chronologies held by the ITRDB via FTP from ftp://ftp.ngdc.noaa.gov/paleo/treering A number of directories exist to choose from; chronologies, forast, measurements, reconstructions, software and more. Here, you will notice that the chronologies have been broken down into geographical regions, and you need not down-load all chronologies, just the ones you may be interested in. For example, if I wanted to only investigate tree-ring data from South America, I would get "samerica.exe" (make sure transfers are done in binary mode). These are "self-extracting" EXE files - once they are placed on your computer, just run them (e.g. type "samerica" at a DOS prompt or double click on them in a program manager) and the chronology files will be extracted automatically. The ITRDB Home Page can be accessed through the World Wide Web at http://www.ngdc.noaa.gov/paleo/treering.html Links from this home page are available to the chronology subdirectory, from where the chronologies can be exported. The entire set of chronologies, as well as software used to display and retrieve the data, can also be obtained on diskette by contacting the Data Manager of the ITRDB: Bruce Bauer, Paleoclimate Program, NOAA/NGDC, 325 Broadway E/GC, Boulder, CO 80303 USA, phone: 303-497-6280, e-mail: bab at mail.ngdc.noaa.gov. Q1.3: Contribution of New Data? {top} Q1.3.1: What information should I include with tree-ring contributions? {top} The ITRDB requires specific site information, including: State or Country, Name of site, Site code, Elevation (meters), Latitude, Longitude, Species code (four letter abbreviation used by the ITRDB), Species common name, Measurement type (total ring width, maximum latewood density, etc.), Chronology type (Standard, residual, arstan), First year, Last year, and names of all principal investigators. (If you are contributing only raw measurement data, the chronology type is not needed.) The species codes and accepted common names come from the species list maintained by the ITRDB and distributed on the ITRDB Program Library diskette. The ITRDB Program Library includes a program called "Header" that prompts the user for the correct site information, then automatically creates the necessary header lines in either the raw measurement file or the index chronology file. Once the header information is added, the files are essentially ready for contribution to the ITRDB. However, we strongly encourage the contribution of additional information about the data that would be useful to future users. For example, were soil conditions and types detrimental to these data sets? Were these tree-ring data sampled for analysis of insect outbreaks? We would especially appreciate being sent information on the specific standardisation options used. This additional information can be sent as a simple text (ASCII) file, and it will be included with the holdings of the ITRDB (*.txt) for use by potential users. Q1.3.2: What are the minimum requirements for tree-ring data? {top} (1) Each tree-ring chronology must have been developed from at least 10 trees. (2) The minimum length of the final chronology should be at least 100 years. (3) The ITRDB requests contributions of the original tree-ring measurements used to develop the final master chronologies. We make this request to ensure that original measurements are available in the future should new methods and techniques be developed. (4) It is expected that the series have undergone intense scrutiny by the principal investigator to ensure all individual series are correctly crossdated, and that errors during measurement have been minimised. (5) All necessary documentation must be delivered to the ITRDB (for example, all site data or information on publications that used the data) to ensure as much information is archived as possible. Under special circumstances, these requirements can be waived when samples are too few and scarce (as, for example, with archaeological tree-ring material), or when the data were developed for extremely detailed analyses (as, for example, in stem growth analyses)." Q1.3.3: How do I contribute my tree-ring data? {top} Several methods are available: (1) Send the data on diskette to Bruce Bauer, along with the required documentation. (2) Send the data and information as an e-mail message (many programs now let one attach a file to an outgoing message), to Bruce Bauer. (3) Use anonymous ftp to send your data and information to the NGDC server - be sure to place it in the "pub" directory, and let Bruce Bauer know immediately. Bruce Bauer is the Data Manager for the ITRDB. Q1.4: and the Tree Ring Society? {top} The TRS is an international scientific society dedicated to the application of tree-ring analyses to a wide variety of disciplines. The operation of the society is somewhat peculiar, based on comparisons with other scientific organizations. There are no annual dues, but rather, each time a volume of the Tree Ring Bulletin is published it is accompanied by an invoice. The implication is that the $15 US is the cost of the Bulletin, not membership dues. However, the $15 more than covers publication costs, and so, some monies do accrue to the Society. The Tree Ring Bulletin is the only manifestation of the activities of the Tree Ring Society that is apparent to the general membership. Some society funds were expended at the Tucson conference (International Conference on Tree Rings, Environment and Humanity: Relationships and Processes, May, 1994) to support the meeting, particularly in assisting scientists from distant countries to attend. Also, members of the Society have been active in the planning and implementation of past international tree-ring conferences. ---------------------------- 2. The Forum Q2.1: And how about this email forum, the ITRDB Forum? {top} The ITRDB email forum helps dendrochronologists to keep in contact and supports those collecting and developing tree-ring chronologies throughout the world. Anyone interested in dendrochronology can participate in the forum. The forum operates through the Internet, and can be used by members to address important issues confronting dendrochronologists in current research efforts. The forum can be used to (1) discuss current issues relevant to tree-ring research; (2) announce upcoming meetings relevant to dendrochronologists, (3) announce the publication of articles relevant to dendrochronology, (4) communicate personally with other members of the forum, and (5) announce news items that other scientists may find useful. New participants are encouraged to submit a short, one paragraph outline of interests and current research to inform members who may have similar interests. Messages sent to the forum are automatically routed to the entire membership. The address for the forum is: ITRDBFOR at LISTSERV.ARIZONA.EDU Participation in the forum is strictly optional, but it is more useful if a large number of researchers actively contribute. Two options are available for those wishing to join the ITRDB forum. It is preferable to send an interactive mail message to the forum server at the University of Arizona Mail facility using your respective computer system. Send the command "subscribe itrdbfor " as a one-line text in the mail message (please omit the brackets) to the following address: LISTSERV at LISTSERV.ARIZONA.EDU For example, to join the forum using the Mail facility on a DEC VAX computer, simply send the following one-line message: subscribe itrdbfor Jo Smith If you have difficulty subscribing to the forum interactively, write to Henri Grissino-Mayer directly using the address below, either by electronic mail or by normal postal service, and he will make every effort to see that you join the membership. Dr. Henri D. Grissino-Mayer Department of Geography The University of Tennessee Knoxville, Tennessee 37996, U.S.A. 865-974-6029 (office); 865-974-6025 (fax) grissino at UTKUX.UTCC.UTK.EDU Q2.2: How do I subscribe/ unsubscribe/ stop my mail while I'm away? {top} If you plan on leaving for an extended period, you should temporarily take yourself off any list to which you belong. For the ITRDB forum, send this simple one-line message to listserv at listserv.arizona.edu: set itrdbfor nomail Upon your return, send the message: set itrdbfor mail Below is a list of commands that can be sent to the same address to get more information: Help Obtains this short list Info Order documentation SUBscribe itrdbfor Subscribe to a list SIGNOFF itrdbfor Sign off from a list REView itrdbfor Review a list Query itrdbfor Query your subscription options SET itrdbfor options Update your subscription options GET filename filetype Order a file from LISTSERV Q2.3: Why shouldn't I just use the "Reply" function? (why shouldn't I ask Henri this question?) {top} Basically, when one uses the "reply" function, then your message will be seen (and possibly read) by all on the forum. Please make it a habit NOT TO REPLY to a message, and send to the address of the individual you are in correspondence with. Of course, the "reply" function is OK if you want to address the whole Forum on an issue. ---------------------------- 3. Dendro Basics Q3.1: What is Dendrochronology? {top} Dendrochronology is defined broadly to include all tree-ring studies where the annual growth layers have been assigned to or are assumed to be associated with specific calendar years (Hal Fritt's "Tree Rings and Climate") Dendrochronology (ca. 1928): the science of dating events and variations in environment in former periods by comparative study of growth rings in trees and aged woods. (Websters Ninth New Collegiate Dictionary, 1990 ed.) Q3.2: Subfields of Dendrochronolgy? {top} In our post-modernist society all these hang-ups over reductionism and the need to define everything is rather dated, but if you really, really wish to learn about possible sub-fields (in the loosest possible sense) then please read on. Dendrochronology may be divided into a number of subfields, each of which covers one or more aspects of the use of tree-ring data: DENDROCLIMATOLOGY: This is the oldest and probably also the most widely practiced subfield of dendrochronology, being concerned with measuring the widths, densities or other characteristics of annual rings in selected trees at a certain site with the aim of producing an averaged tree-ring chronology for that site. This enables one to study past and present climatic conditions and attempt palaeoclimatic reconstructions. DENDROGEOMORPHOLOGY: This is the application of dated tree-rings to the investigation of landforms and geomorphic processes. eg. mass movement, accumulation processes and avalanche analysis. DENDROGLACIOLOGY: The application of dated tree-rings to the study of glacial related process such as glacial fluctuations. DENDROHYDROLOGY: Utilizes tree-ring data to study hydrological problems such as past variations in stream flows, lake levels and flood history. DENDROECOLOGY: A subfield of dendrochronology which encompasses all the subfields utilising dated tree rings to study ecological problems and the environment, for example: climate (dendroclimatology), streams (dendrohydrology), geomorphic processes (dendrogeomorphology), glacier movements (dendroglaciology), snow, tectonic processes, fire, forest stand dynamics, anthropogenic inputs, etc. Note: According to Hal Fritts' definition (pers. comm.), dendroecology does NOT encompass the above mentioned fields, but draws upon them as environmental inputs, and differs from them as it focuses on community and ecosystem changes and environmental conditions past and present. DENDROCHEMISTRY: The use of tree rings to document trends in chemical constituents of tree rings (whether organic or heavy or trace metal concentrations). DENDROPYROCHRONOLOGY: The use of tree rings to document the history of past forest fires. (Note - originally termed "pyrodendrochronology,") DENDROARCHAEOLOGY(DENDROHISTORY): System of scientific methods used to determine the exact time span of a period during which timber has been felled, transported, processed, and used for construction. Q3.3: What is crossdating? {top} The procedure of matching ring-width variations and other structural characteristics among trees that have grown in nearby areas, allowing the identification of the exact year in which each ring was formed. See also Q6.3.2. Q3.4: Why is crossdating so important? {top} Crossdating is perhaps the MOST CRUCIAL PROCEDURE in tree-ring analysis. It is of vital importance in assuring that each ring width/ climatic value/ density value/ isotopic measurement/ etc. is placed in its proper time sequence. One commonly finds tree-ring and climatic studies where only rings counts are made. Chronologies resulting from such studies can contain errors due to counting, mistaken identification of ring features and ring absence. A surprising number of absent sets or false rings occur, even for sites that are relatively temperate. Through cross-dating, these problems can be ameliorated. Q3.5: Methods of crossdating? {top} 1. Directly from Wood: This is the classic method performed by A.E. Douglass (the grand-daddy of North American dendro) and his pupils. A dendrochronologist with many years of experience in a particular area carries the patterns of hundreds of years of ring width variations in his/her head and can compare an observed pattern with this mental reference. 2. Skeleton Plots: This is the graphic representation of those rings considered important in crossdating. In the case of the stress-grown conifers, for which the method is normally most suited, these indicator years are the narrow rings. The method is explained in detail by Stokes and Smiley (1968)- see Q4.1. In the last decade, the method has been 'expanded' to facilitate dendroecological studies. This has been referred to as 'event dating' and graphically 'maps' event years, suppression and release and other variables seen on the wood itself. For an in depth explanation see: Schweingruber, F.H., Eckstein, D., Serre-Bachet, F. and Bräker, O.U., 1990: Identification, presentation and interpretation of event years and pointer years in Dendrochronology. Dendrochronologia, 8: 9-38. 3. Crossdating using measured ring widths: The usual procedure is to plot measured ring widths in a linear scale representing the years of growth for the x-axis and either a linear or logarithmic y-axis for the width of each ring. The dating is carried out on a light box by superimposing one or more graphs. 4. Computers and crossdating: Although the human brain is very efficient at crossdating, the process lacks the objectivity demanded of a scientific discipline. Since the mid 1960's a steady evolution of computer programs for tree-ring research have been written, which has now culminated in the ITRDB Program Library. The latest version is now available and more information about it and its programs can be found in Q5.2. 5. Statistical tests An example of non-parametric tests is the sign test, which proceeds through the following steps: 1) The sign test is a non-parametric method in which the percentage of agreement of tree-ring width in any one year is determined between two series. For example, in year t, tree one increases in width as does tree two; in year t+1, tree one decreases while tree two decreases; in year t+2, tree one increases while tree two decreases. Two agreements, one disagreement, equals percentage of agreement of 67%. 2) First applied to dendrochronological techniques by Gladwin in the 1930's and 1940's, published in 1940 in Medallion Papers 27, as a response to Douglass's more subjective skeleton plotting methods. To his credit, Gladwin emphasized not only year-to-year agreement, but also the intra-annual agreement between two series how much of the ring width variation in any one year was in agreement? However, the statistical properties were never fully worked out. Gladwin was also highly suspicious of statistical techniques. His only publication on this is not a particularly convincing case of correctness in crossdating. 3) At approximately the same time in Europe, in 1943, Bruno Huber published a classic paper entitled "Uber die Sicherheit jahrringchronologischer Datierung" ("On the accuracy of dendrochronological dating") four years before Douglass published "Precision of ring dating in tree-ring chronologies." In this paper, Huber developed the "Gegenlaeufigkeitsprozent," or (roughly translated) the "running dissimilarity percentage". In later years, this was transformed slightly to become the "Gleichlaeufigkeit" or "running similarity" (here we will call it "%A"). Unlike Gladwin, Huber thoroughly developed the statistical aspects of this coefficient. 4) Total value in any one year ranges between zero and one. Two curves are used, and a value of plus or minus one-half is assigned to each year depending on the direction of ring growth. Both decreasing equals (-1/2) + (-1/2) = one. One increasing and the other decreasing equals (1/2) + (-1/2) = zero. One increasing and the other steady = (+1/2). More agreements will equal a high value for the "Gleichlaeufigkeit." 5) Huber showed that a hypothetical sampling distribution could be developed based upon the "Gleichlaeufigkeit," thereby establishing confidence intervals based on standard deviation units that helped resolve how statistically significant a match was between two series. One standard deviation is equal to 50/sqrt(n) so that 95% (2 SD) and 99% (3 SD) confidence levels could be established. Note that problems due to autocorrelation are still present and bias these statistics somewhat. 6) Today, the "Gleichlaeufigkeit" is an integral component of statistical crossdating in European laboratories. This coefficient is always output in the program CATRAS, along with the other more parametric statistics, to help validate the accuracy of crossdating. This method of crossdating, firmly established in Europe, is curiously absent from methods employed in the United States and elsewhere. Q3.6: Principles of Dendrochronology? {top} Most information for this section was taken from the following sources: Henris ultimate Tree-Ring Home Page http://web.utk.edu/~grissino The RING Foundation, Dutch Centre for Dendrochronology, Amersfoort http://www.frw.uva.nl/secties/ring/ Fritts, H.C., 1976. "Tree Rings and Climate". Academic Press, London, UK. Cook, E.R. and Kairiukstis, L.A. (eds)., 1990. "Methods of Dendrochronology. Applications in the environmental sciences". Kluver. Dordrecht, Boston, London. Q3.6.1: Basic Definitions? {top} Tree ring A layer of wood cells produced by a tree or shrub in one year, usually consisting of thin-walled cells formed early in the growing season (called earlywood) and thicker-walled cells produced later in the growing season (called latewood). The beginning of earlywood formation and the end of latewood formation form one annual ring, which usually extends around the entire circumference of the tree. Tree-ring chronology A series of measured tree-ring properties, such as tree-ring width or maximum latewood density, that has been converted to dimensionless indices through the process of standardisation. A tree-ring chronology therefore represents departures of growth for any one year compared to average growth. Standardisation The process that removes undesirable long-term variations from a time series of measured tree ring properties by dividing the actual measurements by those predicted from a statistically derived equation that relates tree growth over time to tree age. Usually this process tries to remove the growth trends due to normal physiological ageing processes and changes in the surrounding forest community. ARSTAN is probably the most commonly used program to undertake this detrending process. Sensitivity The growth of trees can be affected by slope gradient, sun, wind, soil properties, temperature and snow accumulation. The more a trees rate of growth has been limited by such environmental factors, the more variation in ring to ring growth will be present. This variation is referred to as sensitivity and the lack of ring variability is called complacency. Trees showing sensitive rings are those affected by conditions like slope gradient, poor soils, little moisture. Those showing complacent rings have generally constant climatic conditions such as a high water table, good soil, or protected locations. Increment borer An auger-like instrument with a hollow shaft that is screwed into the trunk of a tree and from which an increment core is extracted using an extractor (a long spoon inserted into the shaft that pulls out the core). These instruments are quite expensive, normally ranging from $200 to $500. For more information on borer purchase check out the relevant sections in section Q 7.0. Q3.6.2: Basic Principles? {top} The Uniformitarian Principle The Principle of Uniformitarianism was not realised until 1785, when a Scotsman, James Hutton, presented 2 papers entitled, "Theory of the Earth with Proof and Illustrations". He recognised the cyclical nature of geological changes, and the way in which ordinary processes, operating over long time intervals, can effect great changes. The fact that natural processes of today also would have operated in the past led to the statement: "The present is the key to the past" Uniformitarianism, however, does not just apply to physical processes. In dendrochronology, the principle states that physical and biological processes that link current environmental processes with current patterns of tree growth must have been in operation in the past. This does not mean to say that the conditions are exactly the same but that similar kinds of influences affected similar kinds of processes. Dendrochronology also adds a new "twist" to the principle: "the past is the key to the future". "Study the past to divine the future" (Confucius, ca. 500 BC) In other words, by knowing environmental conditions that operated in the past (by analysing such conditions in tree rings), we can better predict and/or manage such environmental conditions in the future. The Principle of Limiting Factors As stated from Fritts (1976), "a biological process, such as growth, cannot proceed faster than is allowed by the most limiting factor. If a factor changes so that it is no longer limiting, the rate of plant processes will increase until some other factor becomes limiting." This principle is important to dendrochronology because ring widths can be crossdated only if one or more environmental factor become critically limiting, persists sufficiently long and acts over a wide enough geographic area to cause ring widths or other features to vary the same way in many trees. The Principle of Aggregate Tree Growth This principle states that any individual tree-growth series can be "decomposed" into an aggregate of environmental factors, both human and natural, that effected the patterns of tree growth over time. For example, tree-ring growth in any one year is a function of an aggregate of factors: * the age related growth trend due to normal physiological ageing processes * the climate that occurred during that year * the occurrence of factors within the forest stand (e.g. a blow down of trees) * the occurrence of factors from outside the forest stand (e.g. an insect outbreak that defoliates the trees, causing growth reduction) * random (error) processes not accounted for by these other processes. Therefore, to maximise the desired environmental signal being studied, the other factors should be minimised. For example, to maximise the climate signal, the age related trend should be removed, and trees and sites selected to minimise the possibility of internal and external ecological processes affecting tree growth. The Principle of Ecological Amplitude This principle states that a tree species will be more sensitive to environmental factors at the latitudinal and elevational limits of its range. This is important because tree species most useful to dendrochronology are often found near the margins of their natural range. Often the growth of trees near arid forest limits is most affected by drought, while the growth of trees near the upper elevational or high latitudinal forest limits is most affected by low temperatures. The Principle of Site Selection This principle states that sites useful to dendrochronology can be identified and selected based on criteria that will produce tree-ring series sensitive to the environmental variable being examined. For example, trees that are especially responsive to drought conditions can usually be found where rainfall is limiting, such as rocky outcrops, or on ridgecrests of mountains. Therefore, a dendrochronologist interested in past drought conditions would purposely sample trees growing in locations known to be water-limited Sampling trees growing in low-elevation, mesic (wet) sites would not produce tree-ring series especially sensitive to rainfall deficits. The dendrochronologist must select sites that will maximise the environmental signal being investigated. The Principle of Crossdating This principle states that matching patterns in ring widths or other ring characteristics (such as ring density pattern) among several tree-ring series allow the identification of the exact year in which each ring was formed (after Kaennel and Schweingruber 1995, see Q4.1). For example, one can date the construction of a building by matching the tree-ring patterns of wood taken from the structure with tree-ring patterns from living trees. The Principle of Replication This principle states that the environmental signal being investigated can be maximised, and the amount of "noise" minimised, by sampling more than one stem radius per tree, and more than one tree per site. Obtaining more than one increment core per tree reduces the amount of "intra-tree variability", in other words, the amount of non-desirable environmental signal peculiar to only tree. Obtaining numerous trees from one site and perhaps several sites in the region, ensures that the amount of "noise" (environmental factors not being studied, such as air pollution)is minimised. ---------------------------- 4. Dendro Information Q4.1. What are the standard texts in the fields? {top} Baillie, M.G.L., 1982. "Tree.ring dating and archaeology". Croom Helm, London, Canberra. Cook, E.R. and Kairiukstis, L.A. (eds). 1990. "Methods of Dendrochronology. Applications in the environmental sciences". Kluver. Dordrecht, Boston, London. Fritts, H.C. 1976. "Tree Rings and Climate". Academic Press, London, UK. Hughes, M.K., Kelly, P.M., Pilcher, J.R., LaMarche, V.C. 1982. "Climate from tree rings". Cambridge University Press, Cambridge, London, New York, New Rochelle, Melbourne, Sydney. Kaennel, M. and Schweingruber, F.H., 1995. "Multilingual Glossary of Dendrochronology". Haupt Publishers Berne. Stuttgart. Vienna. Schweingruber, F.H. 1988. "Tree Rings: Basics and Applications of Dendrochronology". Kluwer Academic Publishers, Dordrecht, Netherlands. Stokes, M.A. and T.L. Smiley. 1968. "An Introduction to Tree-Ring Dating". University of Chicago Press, Chicago, IL, USA. Q4.2: key papers? {top} The contents of a list of key papers will depend upon the area that is of interest to you. Consequently, the following list covers a broad range of areas and should be treated as a starting point for your investigation. References have also been sprinkled through the FAQ in relation to specific topics, so we suggest that you investigate these and the reference books listed in Q4.1, or check out the dendro bibliography (Q4.7). Alestalo, J., 1971. Dendrochronological interpretation of geomorphic processes. Fennia, Societas Geographica Fenniae, 105 (1-140) Burrows, C.J. and Burrow, V.L. 1976. Procedures for the study of snow avalanche chronology using growth layers of woody plants. Institute of Arctic and Alpine Research, University Colorado, Boulder, Occasioanl Pape. 23 (39) Cook, E.R. and Peters, K. 1981. The Smoothing Spline: A new approach to standardisation forest interior tree-ring width series for Dendroclimatic studies. Tree-Ring Bulletin 41 (45-53) Cook, E.R., Briffa, K.R., Meko, D.M., Graybill, D.A. and Funkhouser, G., 1995. The segment length curse in long tree-ring chronology development for palaeoclimatic studies. Holocene, 5, 2 (229-237) Douglas, A.E., 1921. Dating our prehistoric ruins. Natural History, 21 (27-30) Douglas, A.E., 1939. Crossdating in dendrochronology. Journal of Forestry. 39 (825-831) Eckstein, D (19xx). Dendrochronological Dating: Handbooks for Archaeologists. European Science Foundation, ISBN 2-903148-39-2 Fritts, C.H., 1971. Dendroclimatology and Dendroecology. Quaternary Research, 1 (419-449) Jozsa, L. 1988. Increment core sampling techniques for high quality cores. Forintek Canada Corp. Special publication No. SP-30. ISSN #0824-2199. Schweingruber, F.H., Eckstien, D., Serre-Bachet, F. and Braker, O.U., 1990. Identification, presentation and interpretation of event years and pointer years in dendrochronology. Dendrochronologia 8 (9-38) Shroder, J.F. Dendrogeomorphology: Review and new techniques of tree-ring dating. Progress in Physical Geography 4 (161-188) Q4.3: journals? {top} There are two main journals which are devoted to tree-ring studies: The Tree Ring Bulletin Laboratory of Tree-Ring Research, Building 58, University of Arizona, Tucson. Arizona 85721, USA Subscription: US$ 15.00 per year Editor: Dr. Jeffrey S. Dean Dendrochronologia Instituto Italiano di Dendrochronologia, c/o Museo Ciuico di Storia Naturale di Verona Corsa Cavour, 11, I-37121 Verona. Italy Subscription: US$ 40.00 per year Director: Dr. Elio Corona Other journals include "Tree Ring" (Jumoku-Nenrin), published in Japan and reporting on the annual meeting of the Tree Ring Society of Japan, and various ecological and forest research journals. The Canadian Journal of Forest Research has become a refereed international journal that often contains tree-ring related research papers. Q4.4: WWW Home Pages? {top} A good start would be Henri Grissino-Mayers Home page. This is truly super and is full of information and pictures. Henris ultimate Tree-Ring Home Page http://web.utk.edu/~grissino/ The following list contains some interesting www pages related to tree rings. Henri's ultimate Tree-Ring Home Page http://web.utk.edu/~grissino Bundesforschungsanstalt für Forst- und Holzwirtschaft, University of Hamburg http://www.dainet.de/bfh/ins4/dendro.htm Centre d'études nordiques http://www.ulaval.ca/vrr/rech/Regr/00070.html Cliff Ecology Research Group - University of Guelph, Canada http://www.uoguelph.ca/botany/cerg/cerg.htm Climatic Research Unit, University of East Anglia, Norwich, England http://www.cru.uea.ac.uk/cru/cru.htm Dendrolabor Hohenheim http://www.uni-hohenheim.de/~pkdb/dendro.html The Dutch Centre for Dendrochronology (Ring Foundation) http://www.archis.nl/ring/ General pages on forestry, forest and wood science: http://sylva.for.ulaval.ca/ http://www.metla.fi/info/vlib/Forestry/ General Links: MANY TREE-RING RELATED LINKS...CHECK IT OUT!!! http://www.kcbbs.gen.nz/users/af/cys_tree.htm Instituto Italiano di Dendrocronologia http://lenna.easynet.it/enti/iid/ ITRDB Home Page http://www.ngdc.noaa.gov/paleo/treering.html ITRDB holdings can be searched, and chronology files retrieved, from: http://www.ngdc.noaa.gov/paleo/ftp-treering.html The Laboratory of Tree-Ring Research http://www.LTRR.Arizona.EDU/ The Laboratory of Wood Anatomy and Dendrochronology, University of Lund http://www.geol.lu.se/personal/ore/netsc/dendro.xtm Lamont-Doherty Earth Observatory Tree-Ring Laboratory http://www.ldeo.columbia.edu/trl/index.html The Malcolm and Carolyn Wiener Laboratory for Aegean and Near Eastern Dendrochronology http://www.arts.cornell.edu/dendro/ NOAA Paleoclimatology Program Home Page http://www.ngdc.noaa.gov/paleo/paleo.html The PISCES Laboratory at UCLA http://www.geog.ucla.edu/faculty/glen/pisces.htm Quaternary Biogeography Laboratory, Queen's University at Kingston, Canada http://qsilver.queensu.ca/~js25/ The Sheffield Dendrochronology Laboratory http://www.shef.ac.uk/uni/academic/A-C/ap/dendro/dendro.html The Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) http://www.wsl.ch/forest/dendro/english.htm Sylva W3 http://sylva.for.ulaval.ca/ The University of Georgia Tree-Ring Laboratory http://www.ggy.uga.edu/resources/tree-ring/ The University of Victoria Tree-Ring Laboratory http://geography.geog.uvic.ca/dept/uvtrl/uvtrl.htm The Wood Biology and Tree Ring Research Group http://www.boku.ac.at/zun/wood.htm Q4.5: Other electronic sources? {top} FTP sites: Tree Ring Chronologies ftp.ngdc.noaa.gov/paleo/treering/chronologies Tree ring bibliographic database ftp.LTRR.Arizona.EDU/pub/biblio ITRDB Program Library ftp.ltrr.arizona.edu/sys/home/anonymou/pub/itrdblib Q4.6: How do I translate Feuerwunde and Zellwandwachstum? {top} Try looking them up in the "Multilingual Glossary of Dendrochronology" by Michele Kaennel and Fritz Schweingruber, WSL, CH-8903 Birmensdorf, Switzerland. Published by WSL (the Swiss Federal Institute for Forest, Snow and Landscape in Birmensdorf) and Paul Haupt, a Swiss publisher. Information on obtaining this glossary is available from WSL. The Glossary aims to provide researchers with simple and clear translated definitions for the most widely used dendrochronological concepts and techniques and for some of the commonest terms used in the many application fields. Languages include: English, German, French, Spanish, Italian, Portuguese and Russian. Q4.7: Where do I find the dendro bibliography? {top} The Bibliography of dendrochronology is now available as a database which you can search on the World Wide Web (if you have a Web browser that provides good support for forms). You can find the instructions on how to do this at http://www.ltrr.arizona.edu/archive/biblio.html It can also be obtained in compressed ascii format via anonymous ftp from ftp://ftp.ltrr.arizona.edu/ this connects you to the home directory "/SYS/HOME/ANONYMOU/". Change directory to /pub/biblio and "get" the biblio files from there (use binary transfer mode). If you don't have "pkunzip" on your machine you will have to get this file as well so that you can unzip (decompress) the biblio files. Q4.8: The European Catalogue of Tree-Ring Chronologies. {top} Jennifer Hillam and a group of European dendrochronologists have compiled a computerised catalogue that documents the vast amount of tree-ring data that exists in Europe. The following links present edited exerts from a paper entitled "The European Catalogue of Tree-Ring Chronologies" written by Jennifer Hillam, published in Dendrochronologia. Q4.8.1: Background {top} Due to the concerns of the growing mass of tree-ring data within Europe, a catalogue (not a data bank) has been compiled to provide information on tree-ring laboratories, their chronologies and their research interests. To obtain data, one must make direct contact with the laboratories themselves. In this way the laboratory would still have control over the uses of their data. The working party that was set up to develop the catalogue are Jennifer Hillam, Sheffield Dendrochronology Laboratory; André Billamboz of the Dendrochronologisches Labor, Gaienhofen-Hemmenhofen, Germany; Georges Lambert of the Laboratoire de Chrono-Écologie, Besançon, France, and Pauline van Rijn of RING Amersfoort, The Netherlands. In 1994, Pauline van Rijn was replaced by Esther Jansma, also of RING, and this working party still continues. Q4.8.2: Objectives of the Catalogue {top} The main objective of the Catalogue are: * to promote communication and co-operation between European dendrochronologists * to inform about the research aims of each laboratory * to encourage the exchange of data with special emphasis on the construction of consistent regional chronologies * to document the vast amount of data which now exists in Europe and, at the same time, to highlight temporal and geographical areas which are under-represented by tree-ring data * a long-term aim is for further co-operation on data storage In order to achieve these aims, the catalogue lists information about site chronologies, and participants are invited to provide as much information as they can about each chronology. Therefore the catalogue is not seen as an alternative to the ITRDB, but as a supplement. At the Travemünde meeting in 1994, it was suggested that participants donate chronologies from living trees to the ITRDB even if they were reluctant to give data from archaeological and historical material. Q4.8.3: Participants {top} Submission of data to the catalogue can be undertaken by any laboratory or individual that has produced or published chronologies. Where possible information should be sent via e-mail to aid the input of the details into the catalogue. Initially, access to the catalogue will be to those who have contributed to it. Q4.8.4: Information listed in the Catalogue {top} The catalogue is divided into two sections: (1) List of laboratories, including a presentation of methods and research interests. (2) Catalogue of chronologies. Q4.8.5: Collecting and Displaying the information {top} A simple DOS program for inputting the chronology and laboratory details was written by Esther Jansma (this program can be obtained from Jennifer Hillam) Chronology lists are then converted to Mappad files. MAPPAD version 2.0 (Beta 4) was written by John Keltner and Lou Maher for the NOAA Palaeoclimatology Program, Boulder, Colorado. It can be downloaded from: http://www.ngdc.noaa.gov/paleo/mappad.html Laboratory and chronology information can be displayed by clicking on symbols on maps. Thus clicking on the site of a laboratory will bring up the information about that laboratory. Alternatively, clicking on a site on the chronology map, will show the details of that chronology. Q4.8.6: The Future of the Catalogue {top} The European Catalogue version 1.0 is currently being circulated to participants for checking and comments. 43 laboratories or individuals have provided details for about 1900 chronologies . It is proposed that the catalogue be put on the internet, probably attached to the Sheffield web page and that yearly summaries will be published in Dendrochronologia. In the future, options may be added to select for other information: regional or site chronologies; living trees or archaeological sites, and so on. If anyone has any suggestions about the future development of the catalogue, they should contact Jennifer Hillam. ---------------------------- 5. Software Q5.1: What software is available? {top} There are many software packages available for use in tree-ring work and personal preference depends mainly on where one is working from. Also many labs have their own software packages which cannot be covered by the scope of this FAQ. Most tree-ring programs in America are included in the ITRDB Program Library (Q5.2). Other packages include TREERING 3(Q5.4.4), a tree growth and cambial activity model produced by Hal Fritts and Alex Shaskin, PRECON (Q5.4.2), a package produced by Hal Fritts for analysing tree growth-climate relationships, FHX2 (Q5.4.5) developed by Henri Grissino-Mayer for the analysis of event chronologies and DendroScan (Q5.4.7) developed by Thierry Varem-Sanders and Ian Campbell for x-ray density analysis. European software packages include TSAP, TREND, SUMMARY and CATRAS (Q5.3) and PPP-Base. Q5.2: What's the ITRDB Program Library? {top} The ITRDB Program Library is a software package which was designed to facilitate the development of tree-ring chronologies more easily and efficiently than in the past. The ITRDB Program Library Version 2.1, has the following: 1. The FULL-feature version of Richard Holmes's Dendrochronology Program Library (DPL) which includes the FULL-feature version of COFECHA. The DPL contains some 30 routines crucial to tree-ring analysis. 2. The FULL-feature version of Edward R. Cook's program ARSTAN. This program is considered an important tool for the standardisation of tree-ring data. 3. ITRVIEW 2.0, developed and contributed by Thierry Varem-Sanders of the Canadian Forest Service in Edmonton, Alberta. It has a graphical user interface that is very user-friendly, and has a powerful set of routines for viewing and printing your tree-ring series. ITRVIEW 2.0 has the facility to move series backwards and forwards relative to each other. This means that as well as viewing, it can be also used as a pseudo crossdating program by graph matching. The Pearson's Coefficient can be viewed at the bottom of the screen even when the series are moved. 4. For the first time, the Program Library features a measurement program, MEDIR, based on the program PJK5 originally developed by Paul Krusic. The program is specific to Velmex measurement systems. 5. A new conversion program, CORING, was developed and contributed by Oriol Bosch of the Department of Ecology at the University of Barcelona. This is a wonderful menu-driven program that can inter-convert a variety of native formats, such as TRIMS and CATRAS, to other formats. It complements the program CONVERT5 that offers additional features as well. Between these and the conversion routines offered in the DPL, inter-conversion of tree ring formats should be much easier (see Q6.1-6.3). 6. Other programs: VERIFY5, independent observer measurement verification; HEADER, a user-friendly program for adding the header information to the final chronology data sets; SPECIES, lists over 500 species used in tree-ring research; ADDRESS, accesses addresses, phone numbers and e-mail addresses for over 900 dendrochronologists world-wide; CONTRIB, lists the over 100 researchers who have supported the ITRDB in the past by making contributions; full access to DOS via a shell from the Main Menu and from most other programs. 7. If this wasn't enough to overwhelm you - a 110 page, beautifully formatted, full-colour cover, spiral-bound User's Manual is now available as well. It contains ALL documentation for ALL programs distributed by the ITRDB. This documentation has been extensively updated by Henri and Richard, as well as by the contributing programmers. Note that the manual DOES come on the diskette (or via transfer) as help files in ASCII format. So theoretically, you can make your own user manual if you're so inclined, by importing all the help files into your own word processor, formatting it, then printing it out. Or just send us $20 and we'll do all that for you. 8. An article about the history of the ITRDB and its holdings is included (as an ASCII file available via the Help Menu), which also lists vital information on how to obtain the holdings of the ITRDB, how to search the holdings via the World Wide Web, and how to access our Web site here at the Laboratory of Tree-Ring Research. As much information as we could gather concerning the ITRDB is packed into this article! The ITRDB Program Library Version 2.1 is available via anonymous ftp from ftp://ftp.ltrr.arizona.edu/, in the itrdblib subdirectory. The file to get is "extract.exe", which is a self-expanding file of the DPL. Simply run the file to expand it (make sure you have at least 3 MB of hard disk space before you start). The program library can also be obtained on diskette. The diskette is available to anyone FREE of charge. But there is a catch (of course). The ITRDB is able to be an active organisation only if it continues to receive a steady influx of tree-ring data. All they ask is that, if you find the Program Library has helped you in some way develop your tree-ring data, please consider contributing your data to the ITRDB in the near future. Otherwise, they ask for a $US 20 donation for the diskette to offset office costs - this is still a BARGAIN. They are non-profit remember - plus the programmers have graciously contributed many years of their time to help the dendrochronological community overall. If you want to send $20 AND data, so much the better. This is strictly voluntary! Please note: When ordering the ITRDB Program Library and/or the User's Manual, the check or money order should be made out to the "International Tree Ring Data Bank," NOT to Henri (even though I am sure he would love the extra money). Q5.2.1: the DPL? {top} The Dendrochronology Program Library (DPL) is a set of some thirty interactive computer programs which perform data processing tasks and analysis commonly carried out in dendrochronology for chronology development and for applications in ecology, climatology, hydrology and archaeology. Versions of the DPL have been prepared for the VAX and other mainframe computers and for PC-compatible computers. The DPL performs tasks such as crossdating quality control and measurement verification (Program COFECHA : see Q5.2.3), listing of measurements for troubleshooting and documentation, tree-ring data editing and correction, estimating missing (not absent) rings, and chronology development and analysis. It also deals with monthly meteorological data, estimating missing values, checking for homogeneity between stations, and seasonalizing climatic data. Relating tree rings and climate, it computes response and correlation functions, does calibration and reconstructions, and verifies the reconstructions. Other routines do tasks such as changing data formats and preparing or reading casewise files, principal components analysis, constructing correlation matrices, determining the effect of an impact on tree growth , and inventorying data files. The remaining routines carry out other tasks occasionally needed. Q5.2.2: Arstan? {top} Program ARSTAN produces chronologies from tree-ring measurement series by detrending and indexing (standardizing) the series, then applying a robust estimation of the mean value function to remove effects of endogenous stand disturbances. Autoregressive modeling of index series often enhances the common signal. Extensive statistical analysis of a common time interval provides characterization of the data set. Three versions of the chronology are produced, intended to contain a maximum common signal and a minimum amount of noise. Many options are provided to enable you to tailor the processing to a wide variety of situations and purposes. The concept and methodology of Program ARSTAN were developed by Dr. Edward R. Cook at the Tree-Ring Laboratory, Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York. ARSTAN includes several concepts not previously applied to tree-ring chronology development. In 1983 Dr. Cook provided the source code for Program ARSTAN to the Laboratory of Tree-Ring Research at the University of Arizona, where Richard L. Holmes updated the program to ANSI standard FORTRAN-77 and in collaboration with Dr. Cook developed several enhancements. Q5.2.3: Cofecha? {top} Program COFECHA performs data quality control on a set of tree-ring measurements, verifying crossdating among ring measurement series and indicating possible dating or measurement problems. The printout from COFECHA provides documentation demonstrating the quality of crossdating within a tree-ring site. Program COFECHA serves as a tool for the identification and documentation of portions of a tree-ring data set that may have dating errors or important errors in measurement. It may also be used to check crossdating among chronologies from sites within a region. For each series a note is made of segments which correlate poorly with the corresponding segments of the master dating series (the mean of all other series) or which correlate higher at a position other than the position as dated. Single values are noted which have the effect of strongly lowering or raising the correlation of the series with the mean of all other series. Divergent year-to-year changes, absent rings and statistical outliers are listed. Basic statistics for each series appear in a table. If there are series of difficult or questionable dating you may find their probable dating by putting them in a second data file. If the dating for the site is unknown, you may determine preliminary best-fit relationships among the series by giving their file name as the second file with a blank name for the first file. At many research centers Program COFECHA has saved a great deal of personnel time by providing reliable quality control and archival documentation of crossdating. It may be especially useful to an investigator working alone or in a small group, or in dealing with unfamiliar species. Q5.3: European software packages? {top} TSAP: TSAP (Time Series Analysis and Presentation) was designed as a platform for development of individual applications for measurement, database handling, analysing and presentation of time series with special respect to tree-ring data and related series. TSAP was written by Frank Rinn, Heidelberg and Siegward Jaekel, Leimen, Germany. The architecture of TSAP is based on object orientated handling of time series, independant from origin and format (e.g. Tucson- and CATRAS- format as well as other file-formats can be used). Data headers contain header (text, numbers and codes) and data (arrays of numerical values, optionally with markers and comments). Header items can be location, number, specific codes, tree species, soil type, location, state, town, date end and starting date. All data records (header and series values) are loaded to so-called `data stacks'. The output of calculations and printouts can be directed to the screen, a file or a printer. Also in conjunction with the LINTAB measuring device TSAP can record tree-ting measurements. TSAP is distributed by: Frank Rinn, Kuehler Grund 48, D-69126 Heidelberg. Germany Tel: +49 6221314387; Fax: +49 6221315406 e-mail: 100526.2713 at compuserve.com TREND, SUMMARY, VSORT: Thomas Riemer from Goettingen programmed a software package for statistical analysis of tree-ring data. This software is function orientated and can be used for standardisation (TREND), chronology building (SUMMARY) or selection of data by different data characteristics (VSORT). TREND offers different mathematical models for standardisation and you can even follow and interfere with the process on the screen. The software needs the VFORMAT as file-format, but it is also able to transform Tucson format data. The software is available on request from: Dr. Thomas Riemer, Universitaet Goettingen, Forstliche Biometrie und Informatik Busgenweg 4, 37077 Goettingen. Germany. Tel: +49 551 393462; Fax: +49 551 393465 e_mail: triemer at ufobi2.uni-forst.gwdg.de CATRAS: CATRAS is a function orientated program written by Roland Aniol from Schleswig, Germany. It was probably one of the first computer programs used in European dendrchronology. CATRAS can be used for measuring (connected to the ANIOL measuring device) and plotting of tree-ring series, synchronisation using statistical tools, and chronology building. CATRAS uses a specific binary file format which means that data cannot be read in ordinary text-editors. However, Tuscon-format files can be imported and exported. CATRAS can be purchased from: Roland W. Aniol, Stampfmuhle 4, D-24837 Schleswig. Germany Tel: +49 4621 23342 PPP-Base PPP-Base is an integrated software package working under Windows 95/NT including a data file manager module and a statistical analysis module. Format for the data is the dbase III/IV format, but a tool for converting Tucson format is provided. That software is devoted to dendroclimatology and palaeoclimatology. For tree-ring analysis, it includes standardisation, missing data estimation, ARMA analysis, spectral analysis, transfer and response functions, mapping, bootstrap tools and neural network calibration. Reference: Guiot, J., Goeury, C., 1996: Dendrochronologia 14, 295-300 It can be down loaded from the web address: http://medias.meteo.fr/paleo_utils/ Q5.4: Other tree-ring related software? {top} There are many and various tree-ring related software tools available, covering a range of items from growth, through analysis, to display. Q5.4.1: ITRDB Display Software and PaleoVu? {top} The International Tree-Ring Data Bank display and data retrieval software can be obtained from the World Data Center in Boulder, Colorado. This software, designed by personnel of the National Geophysical Data Center, is very nice, fast, and quite user-friendly. This software is used to graphically display all tree-ring chronologies (some 3,000) currently held by the ITRBD. Data can be exported to an ASCII file for importation into a spreadsheet or other graphics package. The software can "filter" the graphical display of chronologies as well (for example, only showing the location of all Picea abies chronologies currently contained in the ITRDB). All tree-ring data are archived by personnel at the National Geophysical Data Center (NGDC) in Boulder, Colorado, which also serves as the World Data Centre - A for Paleoclimatology. To obtain this software via anonymous FTP, connect to: ftp://ftp.ngdc.noaa.gov/ to connect to the World Data Center. Change over to the "paleo" subdirectory, then to the "treering" subdirectory. If you type "dir" here, you will see all that is available. You should obtain all files that are listed (note: sub-directories have a file size of "512" - you can not "get" these), especially the tree ring "readme" file. The software is contained in another directory called "software." You will want to obtain all files in this subdirectory. PaleoVu is a Windows/Mac application designed to allow the same functions as the ITRDB software, both for treering and other types of paleoclimate proxy data. Connect to the above server and change to directory /paleo/softlib/paleovu and download either readmepv.mac or readmepv.win for download and installation proceedures. These applications can also be downloaded via the web from http://www.ngdc.noaa.gov/paleo/softlib.html. Q5.4.2: Precon 5.01? {top} Precon is a user friendly package developed to facilitate analysis of the responses to monthly climatic conditions recorded in tree-ring chronologies. It also allows one to: 1. fit a particular response for a subperiod and then project that response over an independent period to examine changes through time, 2. analyse changing response using Ed Cooks Kalman Filter program. Input data can be any tree-ring chronology in the International Tree-Ring Data Bank format and monthly climatic data arranged in rows by year. Numerous tree-ring chronologies from Western North America and Europe and selected climatic data are included with the program. Menus prompt the user while importing the input data. Individual tree-ring index data are associated with monthly climatic data from 1 to 2 variables for up to 24 months including temperature, precipitation, Palmer Drought Severity Indices, or any other kind of monthly climatic data. The latest version (5.0) allows for 1) reading and analysing earlywood and latewood data, arranging these data to analyse prior growth and 2) accommodating differences of seasons between the Northern and Southern Hemisphere. Once all of the data are read, the program runs a correlation analysis and offers the following: 1. Tables of several statistics related to the correlation of index data with monthly climatic data. 2. Plots of correlation between indices and monthly climatic data. 3. Plots of data points of one selected variable against two other variables. 4. Plots of significant stepwise multiple regression coefficients. 5. Plots of boot-strapped Response Functions with significant coefficients marked. 6. Plots of the time series showing actual, estimated and residuals from the regression or response analysis. The data may be manipulated trying different subperiods, different F-levels, analyses with and without prior growth, and variable interactions including curvilinear effects. The Kalman Filter and the model of Zahner and Greer using PDSI can also be fit to the data and data and time series plots calculated. Thus the user can design a number of hypotheses, consider and compare a variety of response tools and select the ones that best describe the relationships in question. A user can analyse quickly and easily the tree-ring response to variations in climate and obtain publication quality diagrams. Precon Version 5.01 is available either from Hal fritts homepage or can be downloaded by FTP. Home page: http://www.ltrr.arizona.edu/people/Hal/hal1.html FTP site: ltrr.arizona.edu/anonymous/pub/precon Files: Preadme5.zip, precon5.zip If you have recently obtained the previous version, then you may need to down load the binary file PRECONKN.EXE. This file is included in the precon5.zip file. To obtain a copy, one will need to obtain PRCONPCN.ZIP and prconcld.zip. Unfortunately, Hal Fritts cannot release the graphics display program. This has to be obtained from him. Q5.4.3: WinDENDRO? {top} WinDENDRO is a semi-automatic image analysis system specifically designed for tree-ring measurement. It uses optical scanners instead of video cameras. Scanners produce very high resolution colour or black and white images, free of illumination problems (non-uniformity and shadows) often found with camera based systems. WinDENDRO was designed in 1988 in collaboration with Dr. R. Gagnon and Dr. H. Morin at the Dendroecology Laboratory, University of Quebec. It has evolved since then from a single configuration model for Apple Macintosh computers to a multi-model and multi platform system available for Windows 3.1 and 3.11, Windows 95 and NT 4.0 and Power Macintosh (native). Some General features: 1. RING DETECTION Rings can be measured on disk radii or on complex paths. There are two automatic ring detection methods which can be overridden for manual operation. The first method is based on light intensity differences. It is simple, efficient and works fine for contrasted rings like those of conifers. The other method is called Teach & Show and is a method where you show WinDENDRO what a ring is in the image. This method is more computer intensive and is well adapted for low contrasted rings like those of deciduous trees. 2. VALIDATION For greater precision, the operator validates the analysis. This is done by browsing the image and looking for missing or false rings. Adding or deleting rings is easily done by clicking on the image. WinDENDRO also has a built-in crossdating feature to facilitate ring validation. A ring width graph is displayed and is updated as rings are added or deleted. A correlation coefficient between sample and reference data is also calculated. 3. STEM ANALYSIS Stem analysis is done in Microsoft Excel with a set of extensions called XLSTEM. It allows to visualise data produced by WinDENDRO and to do standard growth analysis. From a WinDENDRO file, XLSTEM can produce the following information: * Mean radii, diameter and area for all disks * Tree height and volume as a function of age 4. DENSITY ANALYSIS Density measurement was added to WinDENDRO in 1992 based on a new concept designed by Regent Instruments. With this new method, density values are measured on scanned X-ray film of the pieces of wood (prepared according to standard methods). This is done by measuring the intensity of light transmitted through the film on ring paths. Parameters like slit size can easily be changed. When computing density, WinDENDRO automatically sets the slit angle tangent to the ring angle in order to produce accurate measurements. In addition, the slit angle is changed smoothly between the rings. ADVANTAGES OF REGENT IMAGE ANALYSIS SYSTEMS * The optical scanner can be shared with other REGENTs applications: Win/MacRHIZO for root measurement, Win/MacFOLIA for leaf analysis, Win/MacNEEDLE for needle analysis, Win/MacCOLONY for bacterial colonies counting, Win/MacFUNGI for fungus cultures growth analysis, or general applications like desktop publishing, optical character recognition and teledetection. For more in depth information on WinDENDRO and other REGENT applications contact Regent Guay or try the WinDENDRO web site: http://www.regent.qc.ca/products/dendro/DENDRO.html Q5.4.4: TREERING 3.0? {top} A process model of the response of cambial activity and ring structure to daily climatic variations. This model provides calculations of water balance, photosynthesis, carbon storage, crown growth and cambial activity, then provides graphical outputs showing the daily values of growth regulating processes (e.g. number of cells dividing, enlarging and maturing) along with the resulting ring structure. The model was developed by Harold C.Fritts, Alexander Shashkin of the Institute of Forestry in Krasnoyarsk, Russia and Geoffrey Downes of CSIRO Division of Forest Products, Australia. Note this is a demonstration model only. More information on this model can be found at the web site: http://www.ltrr.arizona.edu/people/Hal/halmodel.html Q5.4.5: FHX2? {top} FHX2 analyses event chronologies, in particular those related to fire scars and other fire history studies as developed from tree-ring data. The software provides means for: 1. entering and storing fire history data 2. graphing and plotting these data 3. statistically analysing the fire history 4. analysing the relationship between fire and climate. Statistical analyses include fire interval tests, seasonality summaries, and tests that detect changes in temporal or spatial aspects of fire regimes. Henri D. Grissino-Mayer developed this software and is responsible for its support and distribution. Note that this software must be purchased to satisfy a distribution license agreement with a third party vendor. More information can be also obtained at the web site: http://www.ltrr.arizona.edu/archive/fhx2/FHX2.html Q5.4.6: Free Palaeoclimatic Software? {top} The NOAA/Palaeoclimatology Program has produced a suite of programs to aid in palaeoclimatological research. PaleoVu: (Version 1.0 for Macintosh and Windows 3.1) is a complete browse and visualisation tool for ALL types of palaeoclimate and palaeoecological data. See Q5.4 SiteSeer: (Version 1.1 for Microsoft Windows) allows the user to browse the contents of a pollen database, displaying summary information and summary pollen diagrams. ShowTime: (Version 0.5 for Microsoft Windows) is an animation that displays the distribution through time and space of individual pollen taxa. MapPad: (for Microsoft Windows) is a program with which you save your site and associated text information to a simple text field, and then display it by clicking points on a map. Continental and regional maps are provided. ITRDB Display Software: (for DOS) displays world-wide site locations, allows searches by location, tree species, or time interval, and displays time series for all sites in the International Tree-Ring Data Bank. See Q5.4 AnalySeries : (MacIntosh) a time series analysis tool. These programs can be downloaded from the website: http://www.ngdc.noaa.gov/paleo/softlib.html A European ftp site is also available to reduce download times for users in Europe. Q5.4.7: DendroScan? {top} DendroScan is a program that works along side a regular desktop scanner to analyses x-ray densities, but also works well with ring widths alone. Resolution routinely is in the order of ca. 20 um but can be fined down to ca. 2 um. The program automatically detects ring boundaries and measures ring widths, and with an x-ray can give the density of each pixel. The ring detecting algorithm has a success rate of 95%+ in conifers and 75%+ in hardwoods. Through the user interface ring boundaries can be added of deleted. Crossdating "on-the-fly", can be accomplished by observing 2 samples simultaneously on the screen and moving them back and forth to find the best match. For the price of $99.95 (Canadian; ca. $72), plus shipping, handling and applicable taxes, one receives: 1. A book detailing how to build and use your own x-ray densitometry facility for less than ca. $20,000 US (including computers and x-ray machine- most academics already have a computer and access to an x-ray machine, so the cost can be a lot less!). 2. The same book has also an extensive user manual for DendroScan, the software at the heart of the system. 3. The software itself (for DOS/Windows/Win95 platforms only) on a 3.5 inch floppy. 4. a high-precision calibration wedge for translating grey-values in your images into densities. To get more information, please contact Dr. Ian Campbell or Thierry Sanders via the ITRDB forum ---------------------------- 6. Data Formats Q6.1: What are all the different data formats? {top} Various formats in use by the ITRDB are: "Decadel format" : for ring measurement series. "ITRDB format" (or index): for tree ring chronologies; this format can also show the number of series included in each year. "Compact format" for any data series: this format has several advantages such as freedom from dimension and precision constraints, but it is hard to visualise data values in this format. "Meteorological data format" for monthly precipitation, temperature or similar monthly data; this format has the year and twelve data values per line. There are several other formats used by different investigators, but these are the most common and widely used. The formats are described in detail in the documentation for the DPL. As far as the format CATRAS, there is no explanation for this, as it is a binary file produced by the CATRAS program. For conversions of European formats, contacting Frank Rinn may help. His software is able to read and convert among about 20 different formats used by European labs. Frank Rinn - Dipl. Phys. Kuehler Grund 48 D-69126 Heidelberg Germany e-mail: 100526.2713 at COMPUSERVE.COM Tel: +49 6221 314387 Fax: +49 6221 315406 Q6.2: Which should I use? {top} It really depends upon what you are working on and with whom you are working. To remain internationally synchronous, try using "decadel" for raw measurements and "ITRDB" for chronologies. Q6.3: Can I convert between them? {top} Yes. Various programs allow interconversion among nearly all data formats these days. Convert5 reads TRIMS, Decadal (.01 and .001) and Catras, and formats to Decadal or Compact. CoRing converts numerous other European formats, and can convert to tabular format (for spreadsheets). The routine FMT in the DPL converts numerous formats as well. ---------------------------- 7. Equipment Q7.1: What equipment do I need to become a dendro? {top} Simply: several pieces of wood, a pencil and some graph paper. See skeleton plotting: Q3.5. A typical dendro field kit may contain some or all of the following: bamboo chopsticks - for poking wood out of the corer tip. (Not that you should ever EVER do this, of course), chain saw, corers (consisting of a "corer bit", an "extractor" or "spoon", and a "handle", within which the bit and extractor are stored when the corer is not in use), CRC/ RP7 spray for cleaning corers (and lubrication - beeswax is also good for lubrication), duct tape, drill extractor - a long piece of high tensile wire with a 2 mm drill welded to the end. Used from the back end of the corer to remove jammed wood in a very slow and careful operation (i.e. get one of your assistants to do it), eye piece/ loupe, field notebook, hammer, hand saw, lighters, maps, nails, pack, pen/ pencil, rags, sharpening stones, sharpies (indelible marking pens), site description sheets, storage tube, straws, sven saw, tree tags, vest, waste paper for cleaning corers, waterproof bag, wire/twine for extraction of corers from trees (see Q8.3), (helicopter and 3 field assistants!) Core Mounting: glue, masking tape, mounts, pencil, string In addition to this, the simplest lab set-up you need would probably be: 1) lots of sanding paper (or preferably a sanding machine and/or a couple more assistants) 2) microscope (with cross hairs and, if available, variable magnification between about 10X and 100X depending upon the size of features under examination) 3) graph paper and pencil (if you are into skeleton plots or similar techniques for crossdating- and if you are not, then maybe you should be. (See Q3.3) 4) measuring stage and computer. (etc, etc, in terms of lab equipment) Q7.2: How do I tell a good corer from an average one? {top} It's all in the bit, particularly the tip. A good dendrochronological corer has a well machined coring bit, with an even wall thickness (you will probably only notice uneven wall thickness after the coring bit has broken!) and an inner diameter that gets smaller in the few millimetres near the cutting tip. With this, the core that you cut is of lesser diameter than the bit, and so is not twisted or otherwise messed up by contact with the inner bit surface as you cut the core. With some cheap (and nasty) corers the inner diameter is almost constant along the entire length, as though the corer had been made from a piece of pipe rather than being machined from a solid section. Q7.3: Where do I get a good corer? {top} The corers of choice for a lot of dendros are made by Haglof AB of Sweden. Haglof have taken over manufacturing the former Mattson corers, so have available both Haglof and Mattson corers. For Haglof International Sales contact: Gabriella Nasholm Haglof AB Box 28, S-882 21 Langsele Sweden Telephone + 46 620 25580; Fax + 46 620 20581 (yes. it's the same number) Note: Each country may have its own dealer who buys bulk from Walktax AB. This could be a cheaper option. For example, Kusche Handelsgesellschaft Heidereutestrasse 33 13597 Berlin Germany Tel. + 49 30 332 3041 Fax. + 49 30 332 3042 Ben Meadows Company PO Box 80549 Atlanta, Georgia 30366-0549 USA Tel: 1-770-455-0907 Fax: 1-770-457-1841 Street Address: 3589 Broad Street Chamblee, Georgia 30341 http://www.benmeadows.com/ mail at benmeadows.com USA/ Canada Tel. 1-800-241-6401 USA/ Canada Fax:-800-628-2068 If more information on corers is needed, Gabriella Nasholm of Haglof AB should be able to supply you with a local contact address. Q7.4: straws? {top} Serviceable straws can be obtained from fast food chains. Sometimes you don't even have to raid the straw dispenser - store managers have been known to hand over hundreds of straws just for the asking. For more specialist items, such as paper straws or long straws it is necessary to look further. Uncle Bob's Popcorn, in Tucson, make and supply paper straws - contact the Laboratory of Tree Ring Research for further details. In any medium to large city there are often plastic straw manufacturers who can cut straws to length - they will probably charge a fee for resetting the machine and then a nominal charge for the straws, so it's best to order five or ten thousand while you are at it. Ed Cook and Paul Krusic at Lamont-Doherty Earth Observatory of Columbia University have a supply of 500 mm long clear plastic straws from such a supplier. Q7.5: a measuring system? {top} Measuring systems are very dear to a lot of people (in more ways than one!!) and there are also commercial implications associated with the choice of particular systems. Consequently, it is advisable to carefully look into the options before deciding to buy. There are two main systems that are in popular use today - Velmex and Lintab. Lintab use tends to be concentrated in Europe, while Velmex has more of a North American usage. The majority of the world (i.e. the rest of us) probably uses a mixture, along with a few Hensen/ Zahn, Aniol and other systems. Also, there is nothing wrong with talking to your "local" physics workshop or someone associated with the tool and die industry to make up your own system. Basically, a measurement system consists of: * A measuring stage - a long, flat thing with a platform that moves back and forth to allow you to examine a sample under a microscope. * An encoder - something to convert either the movement of the platform or the winding of a driving/ lead screw into a signal of some variety. * Converting software and recording program that takes the signal and converts it into measurements. Naturally there is a lot more to it than this, mainly related to precision and ease of measurement and recording. Anyway, some of the details of the Velmex and Lintab systems are: Two general Lintab Systems: * LINTAB I Hardware: travel length 390 (~15in) precision ~10um (=0.01mm) handling one hand crank hand crank circumference 310 mm sensitivity ~37 (1mm->27um) sample carrier 150 x 300 mm * LINTAB II Hardware: travel length 490mm (~15in) precision ~10um (=0.01mm) handling two hand cranks hand crank circumference ~390mm & 180mm sensitivity ~130 (1mm->7.6um) sample carrier 300 x 300 mm Both Lintab systems have the TSAP measurement software module, covering: On-line graphical measurement screen, displaying graph and core Data header masks (number and content of header entries is free) Measurement, correction, averaging, and handling of as many curves as the PCs memory can handle Graphical comparison of the series (shifting) Editing (correction by inserting or deleting rings) Averaging of series on screen Simultaneous correlation of the series to the mean curve during comparison Saving the series in one of the formats covered by TSAP Options for LINTAB: Length -590 mm ,740 mm, 890 mm, [lengths of up to 3 meters on request] Binocular microscopes, directly attached to LINTAB: LEICA GZ6; LEICA MS6 The system is totally encapsulated to protect from water, dust, and debris, something to consider if one is working with decayed samples, or samples from wet, boggy environments. Cores and cross-sections can be measured, with samples weighing up to 50 kg. Address: Frank Rinn & team development, distribution, service: Koehler Grund 48 D - 69126 Heidelberg Germany tel +49 6221 314 387 fax +49 6221 315 406 compuserve: 100526,2713 e-mail: 100526.2713 at compuserve.com The full Velmex system consists of: Unislide stage assembly, Accu-Rite linear encoder, Quick-Chek digital readout, TAB2 remote button, 10' TAC connecting cable. Note that the encoder comes in three resolutions: .01, .002, and .001. The stage comes in various sizes from 3" to 24" resulting in 24 possible combinations that the user can custom-design to suit one's needs. Side mounted hand crank eliminates the need for transfer gears as with some Henson/Zahn systems. The Unislide uses a lead screw as opposed to the belt drive used by the LINTAB system. The measurement software is designed for MACs and PCs and is free of charge. (Featured in the ITRDB program library is a measuring program (MEDIR) based on program PJK5 originally developed by Paul Krusic. This program is specific to the Velmex measurement system). Address: Velmex, Inc., P.O. Box 38, 7550 Routes 5 and 20, East Bloomfield, NY 14443 USA. Phone: 800-642-6446 or 716-657-6151, fax: 716-657-6153 DIGITAL DISPLAY UNITS INSTALLATION (With MANY thanks to Paul Krusic) With the programs MEDIR (found in the ITRDBLIB), PJK5 (Mac) and PJK6DOS (PC), four different digital display units are available for use. Thank you to Paul Krusic for providing his installation notes which normally come with program PJK. 1. AcuRiteIII Single Axis Display 2. Metronics Quick-Check QC-1000 3. Boeckler Microcode II 4. Measurchron (L. Kuchenreiter-Austria) AcuRiteIII Single Axis Display (Renamed in 1993 as Master G) Using the pre-set interface program, make the following changes to the factory's initial default settings. Refer to pages 3-5, 3-6, 3-7 and 3-9 of your AcuRite III RS232 computer/printer interface option manual. It is suggested to write down your current settings before changing them. Baud 9600 Acurite CODE VALUE stopbits 1 21 1 databits 7 22 82 parity even 23 71 24 00 26 12 27 10 28 10 29 10 31 0 42 1 43 0 All other settings should be returned to their default. Program PJK6.AcuRiteIII operates on a one-way communication protocol between the computer and the digital display. Therefore the command to send a measurement to the computer must be initiated by the operator using either the print key on the displays front panel or a remote print switch plugged into the back of the display unit via a din-8 plug. Momentarily shorting pin 2 to 3 of the din-8 plug will activate the send command. AcuRite does offer a foot switch to do this if one cannot find the necessary components to make one ( p/n 388000-107). We recommend all remote switch's, regardless of the display being used, be D-Bounced in order to eliminate any problems with noise in the RS232 communication link. A Schematic for an active D-Bounce switch is available upon request. Voltage bouncing can be dramatically limited by using a good momentary switch, this is the minimum requirement. To connect the AcuRite III to a Macintosh or Mac compatible computer use a standard Modem cable (DB25-mini8) from serial port #2 on the AcuRite to the Mac modem port. Before measuring be sure that the correct units (mm.) are illuminated on the front panel and that the display is set to record cumulative distances measured (ABS). Finally, unlike the other display units, the AcuRiteIII/Master "G" displays allows the user to directly input a value into the displays memory. This feature is used when measuring specimens longer than the stage. Become familiar with this feature and practice resetting the stage position then continuing measurement by manually inputting the last cumulative distance reached before the stage position was changed. Metronics Quick Check QC-1000 *Revised for PC's 1/5/96 Configuring the Metronics Quick Check begins by first making a DB9 to DB25 or DB9 communication cable in order for the RS232 communication to operate correctly through the PC's com ports. Since the first version of this program for Dos computers was released many labs have requested that the software be usable through either comm1 or comm2. Either port may be used with the correct software. The proper version to use is identified again by program name . As this is the most popular display configured for the Velmex stage, a number of configurations for the communication cable are available. You must choose the configuration that best describes the hardware requirements you are using. Quick-Check/DB9 PC/DB25 PC/DB9 Mac Mini8 Function(QC1000) pin # pin # pin# pin# 1 7 5 4 GND 4 3 2 3 TXD 5&7 6,8,20 1,4,6 2 RTS/CTS 8 2 3 5 RXD A remote print switch may be employed by through the RJ-45 "REMOTE" jack on the back panel and momentarily grounding wires 4&5. To zero out the display by remote ground wires 1&6, The Quick-checks internal software must also be configured for use with the measuring program by setting the appropriate baud rate, precision, and RS-232 options. This is accomplished through an internal program activated by a sequence of display panel button strokes outlined in the operators manual that came with the display. The only parameters that must be changed are the following, all else are left at their default settings.The QC-1000 on the Macintosh computer is interfaced through the Mac's phone port and on the PC's through either serial port com1 or com2. Macintosh PC's Baud 9600 1200 Encoder Scale 0.001 0.001 Display Units mm 0.001mm 0.001 mm From personal experience, if an error message appears on the screen or the measurement are always zero when the print button is pressed then there is a problem in the setup of the QC-1000 parameters. If nothing appears on the computer screen then no signal is reaching the computer. One will need to check the DB connections (Rob Wilson). # Attention DOS users! A special note for Dos users. In many respects you have it better than those in the Mac world, but again, there are always trade offs. Over the years a number of peculiar situations have occurred that have hindered easy set up of this software. Advice to Dos users is to begin with you computer setup in the most basic mode. Temporarily disable all init's and especially windows. On a couple occasions third party cards like mouse and game port cards have interrupted the serial communications controllers. Avoid using a port that is on a card with some other external device. Same goes for Mac users, start up you computer with just the minimum of software then add the features you like one by one. # Attention MAC users As of this writing the measuring program WILL NOT run on any MAC other than 030, 040, or older processors. Sorry. PJK is working to update this serious limitation currently and hopefully an improved version will be available by the summer of 97. Boeckeler Microcode II This is the easiest display to configure correctly for use with the measuring program. Open the rear panel and find two 8 position dip-switches, one top and one bottom. The proper configuration for the top switch is all positions off except pins 3 and 5. The proper configuration for the bottom switch is all positions off except pins 6 and 8. Like the AcuRite display, a remote print switch must be configured. This is accomplished by momentarily grounding, for at least 1/msec, pin 25 on the DB25 connector. Connection between the Microcode II to the Mac's communications port is via a DB25-mini8 pin modem cable. Q7.6: other equipment? {top} This section may introduce you to other equipment that is useful in dendrochronology and forest research.: Density Analysis: DENDRO 2003 The DENDRO 2003 has been specifically designed as a tree ring work-station. It is the the third generation of densitometers designed by Walesch Electronic. It can be used in the fields of forest research, wood technology, sedimentology, zoology and photography for the solution of climatological, ecological, technological and historical problems. The DENDRO 2003 system together with comprehensive software (Macintosh only), allows samples with tree rings smaller than 0.1mm to be analysed quickly and reliably. see Eschbach, W., Nogler, P. and Schweingruber, F.H. 1995: Technical advances in the radiodensitometrical determination of wood density. Dendrochronologia. For more information contact Walesch Electronics Frank Rinn Distribution A whole host of equipment is available from this company: RESISTOGRAPH A device that measures the drill resistance of a fine needle as it penetrates wood. Uses: Tests for wood condition/quality, Detects for decay and therefore stability and safety of timber, Growth trend, tree ring widths and density profile. See Rinn, F., Schweingruber, F.H. and Schär, E. 1996. RESISTOGRAPH and X-Ray Density Charts of Wood Comparative Evaluation of Drill Resistance Profiles and X-ray Density Charts of Different Wood Species. Holzforschung 50 (303-311). ELECTRONIC IMPULSEHAMMER Stress-wave timer for defect detection in standing trees. FRACTOMETER Measurement of compression and bending strength of cylindrical samples, i.e. increment cores. For tree inspection, wood quality assessment and research. LINTAB and TSAP Already mentioned elsewhere in the FAQ. Haglöf Increment Borers Lengths range from 100 mm to 1000 mmm. Core diameters: standard 4.3 mm and 5.15 mm but also 8, 10 and 12 mm. 2 or 3 thread borers on request For more information see Q7.3 Where do I get a good corer? Mantax Calipers: Precision calipers with possible lengths from 40 - 127 cm. Mantax Computer Calipers: Computerised presicion calipers to aid in point sampling, plot sampling and scaling loads of trees. DME 201: Electronic distance measuring device. Vertex Hypsometer: Similar technology as the DME 201, but used for tree height measurement. Walktax- Thread Distance Measurer: Marktax Paint Marking System: Quicky, easy environmental method for marking timber and trees. Accessories: Variety of miscelleneous goods: COHO: Borer Holster. VEST: The Cruiser vest. Pockets inside and outside plus much more! COST: Borer Starter. BAM: Bark Thickness Measurer. COHA: Increment Hammer. ---------------------------- 8. Field Work Q8.1: How do I use a corer (safely) ? {top} There are a few general rules that are associated with good quality coring. They are given below (any more suggestions would be welcomed): * Above all else, your field practices must be aimed towards first protecting yourself and other workers, then your samples and equipment. Consequently, always keep in mind the many hazards associated with fieldwork, such as being eaten by bears, crocs and alligators, bitten by snakes and scorpions, crushed by falling trees, breaking limbs, backs and heads by falling off or between branches or trees, and so on. * Given these hazards, the next step is to protect your coring bit tip because the best increment corer for any tree is a really sharp, really clean, tenderly cared for increment corer. Steps to protect your tip include always putting it carefully back in the handle when going from tree to tree, cleaning it every day (or even every core for some species) and having available a good sharpening kit (and the knowledge to use it). * Select a good spot on the tree to core - away from branches; away from tension or compression wood on slopes; away from cracks in lobate growing trees; where you can stand comfortably to operate the corer at breast height (Ed. - I am still dreaming about finding a tree like this!) * Start coring slowly and steadily, without wobbling the end of the handle around - if the handle is not held steadily, then the outer part of your core will not be straight. A corer starter/ breast plate will help to steady the corer. * Continue winding in the corer. In some harder species it may be necessary to back the corer off a quarter or half turn for every inward turn. * When you have reached the desired depth, carefully insert the extractor alongside the wooden core, pressing it firmly (but not too firmly) into place. One of the more frequent corer breakages is snapping the head from your extractor by trying to push it in too hard. * Back off the corer a turn or two (or half way out of the tree for some "grabby" hardwoods.) * Remove and store the core, place the extractor somewhere safe, unwind the bit from the tree and then pack the bit and extractor into the handle before moving to the next coring place. Q8.2: A chainsaw? {top} A full description of good chainsaw techniques is beyond the scope of this FAQ. Your preference should be to take a chainsaw safety course before undertaking any chainsaw work. Failing that, try to obtain and read the chainsaw safety manuals used by your local Government or private forestry people. The manual supplied with your chainsaw also often has safety tips, and talk to people who have been using chainsaws for a while - but be careful of their biases. After all this, make sure you follow the minimum safety requirements for chainsaw usage: * ALWAYS have someone else around when using a chainsaw * ALWAYS have a first aid kit available * ALWAYS wear hearing protectors, a clear face mask and chainsaw safety trousers or "chaps". Q8.3: I've stuck my corer in a tree - how do I get it out? {top} There tend to be two main ways to get corers stuck in trees. The first is to hit a rot pocket or some soft wood, so that the bit will not grip when you try to wind it out. The second way is if you are coring a hard "grabby" species that grabs hold of your corer and defies you to remove it. The solution to both of these is to avoid letting it happen. In grabby species you should aim to keep the bit moving in or out and only stop for the minimum possible time to insert the extractor. For the soft wood or rot problem a first approach is to pull mightily on the corer as you unwind it. Be very careful with the bit retaining clip while you are doing this as there is a risk of injury is the handle comes unclipped from the corer while you are doing this - particularly if you are a couple of metres off the ground and are pushing against the tree with both feet. Some people use hose clamps or "O" rings to keep the clip in place. If this fails, then the alternative is a rope or webbing extractor. This is a loop of rope or a long 25 mm webbing sling placed over the corer bit and around a strong nearby tree such that as the corer handle is turned the rope tightens and pulls on the corer. For details of a corer extraction procedure, please see David Yamaguchi's paper in the Can. Jour. For. Res. 21:712-714. 1991. Q8.4: Does coring damage trees much? {top} In coring any tree there is a level of risk associated with the long term effects of the core hole. The degree of risk depends upon the species being cored and the coring process. In all cases you should use a very sharp corer and should cut a core that slopes slightly upward into the tree, so that water, sap etc drain out rather than into the tree. In general, do not plug holes with dowels or other objects, as they may increase the rate of stem cracking and cambial dieback. Also, do not use wound dressings or paint and do not tag trees with nails or staples. Instead, use a loose loop of wire with a tag on it that can drop to the ground surrounding the tree. The wood of a living tree compartmentalizes in response to wounding. Compartmentalization is the boundary-setting process that tends to limit the loss of normal tissue functioning following the wounding of wood in living trees. The closure of wounds is important, but is largely unrelated to the effectiveness of compartmentalization. Some bore holes close rather quickly, yet extensive internal decay develops. Conversely, some holes close slowly, yet decay development is quite restricted in volume. Where coring can cause a significant amount of decay is in those trees that have already rotted and contain a compartmentalized core of decay ("heartrot"). Coring can break the boundary that kept the infection in the core of the tree, resulting in a spreading of infection out into the sapwood. Wound sealing and compartmentalization is dependent on tree species and time of wounding. E.g. Tilia has a better ability to compartmentalize as Betula, while beech and aspen are sometimes susceptible to coring damage. Coring during the vegetation period gives the tree a better chance to react on the injury, although some studies (see refs below) suggest that coring should be done during dormancy. In coniferous species it also appears that the presence of resin along with the heat generated by friction during coring helps to seal off the core hole walls to most infections. A few comments on individual species examples are: * To the best of my knowledge, there have been no reports of any bristlecone pine mortality induced by coring. (Frank W. Telewski) * Aspen in the Rockies have died from canker infections introduced at the corer hole. However, that has only happened to me once in 25 years of boring trees. (Wayne D. Shepperd) * I have re-visited over 500 tagged oak trees 3-4 years after I initially cored them. In virtually ever case, the two core holes in each tree had completely covered over on the outside. On only 4 of 500 trees did I find evidence of a fungal infection resulting in tissue necrosis around the core hole. (Dave LeBlanc) * In eastern white cedar most of the oldest trees have huge woodpecker holes in them. Also there are no known pathogens in eastern white cedar. I don't feel guilty taking a straw-sized hole out of the side of one of these trees especially when they've survived for hundreds of years under far more arduous conditions.(Pete Kelly) To find more, look into the following references: Lassoie and Hinckley, 1991. Techniques and Approaches in Forest Tree Ecophysiology, CRC Press. Lenz, O. and Oswald, K. 1971. Uber Schaden durch Bohrspanentnahme an Fichte, Tanne und Buche [On defects in wood of spruce, fir and beech caused by increment boring]. Mitteilungen Schweizerische Anstalt fur das forstliche Versuchswesen, Birmensdorf, Vol. 47. 33p. Lorenz, R.C. 1944. Discolorations and decay resulting from increment borings in hardwoods. J. Forestry 42(1): 37-43. Polge, H. and Thiercelin, F. 1970. Degats occasiones par les sondages a la tariere. Revue forestiere Francaise 22(6): 629-636. See also Forestry Abstracts 32(1): 795 (Abstract 6558), January 1971 Shigo, A.L. 1984. Compartmentalization: a conceptual framework for understanding how trees grow and defend themselves. Ann. Rev. Phytopathol. 22:189-214. Shortle, W.C. 1990. Decay column boundary layer formation in maple. Biodeterioration Research 3: 377-389. [Plenum Press] Shortle, W.C. 1995. Response of maple sapwood to injury and infection. European Journal of Forest Pathology 25: in press. Smith, K.T. 1988. Wounding, compartmentalization, and treatment tradeoffs. Journal of Arboriculture 14:226-229. Smith, K.T. and W.C. Shortle. 1993. Effectiveness of compartmentalization of wound-initiated discoloration in red spruce trees of two forest stands. European Journal of Forest Pathology. 23: 244-251. Toole, E.R. and Gammage, J.L. 1959. Damage from increment borings in bottomland hardwoods. J. Forestry 57(12): 909-911. ---------------------------- 9. Sample Preparation Q9.1: How do I safely transport and preserve samples? {top} In general wood samples are fairly robust whether in core or disk form. However, care should always be taken against possible damage during transportation. Cores can be best preserved within paper or plastic straws in a closable carrying tube. Disks are generally stronger and can survive much more battering, however, it is still advisable to tape the disks around the circumference. This helps later on in the lab when the samples are drying and tend to expand and split (especially if dried too quickly). The tape can hold the pieces together. Decayed or excavated samples can pose more problematic. If allowed to dry they invariably have a habit of disintegrating into dust. If possible the samples should be frozen (on site if at all possible). If there is no cold store facilities then samples can be kept wet in polythene bags (keep your fingers crossed that they survive). Q9.2: Sample/surface preparation? {top} This of course will depend on the wood type, ring widths and sample condition. However some general guides to surface preparation are: Ring-porous samples such as Oak, should be first smoothed using a sharp knife (or sanded for tight rings series) and then chalk rubbed into the surface to highlight the early vessels (see powder methods) Diffuse-porous: see specific examples in section Surface Enhancement Conifer samples such as Spruce and Firs can also be prepared using a sharp knife, but for very tight ring series, sanding to fine grits of up to 600 will produce best results. Buffing to produce a glass-like finish is also recommended. Most workers consider hand finishing of cores essential even for those sanded mechanically with the finest grit. Electric planers are very good for quickly putting a smooth, level surface on cross sections and can save a lot of rough grit sanding time. You still have to use fine sanding belts and paper to achieve a good surface, but the planers work well. Wet samples if too wet for slow drying should be frozen for at least 48 hours and then cleaned with a multibladed surfacing tool (Surform Plane) or a sharp knife. They are then left to thaw before measurement. Decayed samples are very problematic and there are no hard and fast rules. Each individual sample is different, and therefore different techniques need to be tried until one is found that works! Some examples can be freezing or just light brushing of the surface. Charcoal sample preparation has been well described by Hall (1939,1946) where full details are given of a paraffin-embedding method for charcoal, including how to trim the surface and remove the paraffin by heat treatment to leave a flat surface for photography. Hall, E.T. 1939. A method of obtaining a plane surface on charcoal. Tree-Ring Bulletin 5(4): 31 Hall, E.T. 1946. Preserving and Surfacing Rotted Wood and Charcoal. Tree-Ring Bulletin 12(4): 26-27 Q9.3: What should I use to enhance the surface? {top} In general, with most species of wood, sanding to very fine grits is quite adequate for most dendrochronological purposes. However, especially with deciduous species, enhancement of the ring boundaries is quite often needed. Below are some general and specific methods of surface enhancement. Powder methods We have coined the phrase "powder methods" to encompass all enhancement methods that use different types of powder to highlight the early vessels in ring-porous samples. Chalk Many workers dating both ring-porous and diffuse-porous species use some form of chalk to fill the early wood vessels to make them clearer. Ordinary blackboard chalk is suitable and convenient for this purpose. The disadvantage is that it makes it more difficult to distinguish between heartwood and sapwood. Magnesium Moisten the smooth surface and rub magnesium (a solid piece works fine) onto the surface. Then when dried wipe away excess magnesium dust. The vessels are filled with magnesium and hence rings are more easily discernible. This method works very well with birch (Betula). See also specific example of Betula pendula ring enhancement. Marker pens and chalk First place tape over the sample and remove to make sure the surface is clean from particles. Blacken the surface with a permanent marker and let dry. Then tap powdered chalk (from blackboard eraser) over the surface. The vessels should be filled with the powder and the rings more discernible. NOTE: In general, powder methods are not very effective with diffuse-porous wood due to the distribution of the vessels throughout the growth ring. Other methods Sappy Wood When working with sappy samples, rub the sample with steel wool. This only works temporarily as the sap refills the cells. (see Q 9.4 How do I get resin off more cores?) Burning Wood In the final stages of wood sanding, if one is using a fine grit (above 400), then a relative low speed and extra pressure can burn the wood. This highlights the latewood. Light Source The changing of light source and/or intensity can help. For example fluorescent light. Ring Staining Some references for sample staining are: Blais, R. 1995. Colorant et filtre excitateur our lamelioration de la lecture des cernes annuels de croissance de certains feuillus. [Stains and exciter filters for improving the clarity of annual growth rings in certain hardwoods.] The Forestry Chronicle 71(2): 211.212. Hornibrook, E.M. 1936. Further notes on measurement and staining of increment cores. Journal of Forestry 34(8): 815-816. Iseli and Schweingruber(1989) Sichtbarmachen von Jahrringen fuer dendrochronologische Untersuchungen. [Making tree rings visible for dendrochronological analyses.] Dendrochronologia 7: 145-157. Kutscha, N.P., Sachs, I.B. 1962. Colour tests for differentiating heartwood and sapwood in certain softwood tree species. USDA Forest Service, Forest Products Laboratory Report No. 2246. 16 pp. Specific examples: Betula pendula Thank you to Fabian Meyer of the WSL for the following technique of sample preparation and enhancement of birch (Betula pendula). These are the steps of core preparation: 1. sanding the cores as usual 2. colour the sanded surface with a red (or any other colour) "edding marker permanent 8300" 3. let the cores dry by the air some hours 4. cut a very thin layer from the surface with a sharp Japanese "NT cutter" knife. The cutter has to be held nearly parallel to the upper side of the core. If you dont, you cut deep into the core and the surface does not stay flat. The more uneven the surface, the more difficult is the measuring afterwards. 5. fill chalk into the pores of the wood. 6. look at the core under the microscope. Often it is necessary to repeat steps 4 and 5 once or twice. 7. note: maybe the chalk becomes coloured after a few days. Therefore cores once prepared should be measured within the next few days Reference: Iseli and Schweingruber(1989) Sichtbarmachen von Jahrringen fuer dendrochronologische Untersuchungen. [Making tree rings visible for dendrochronological analyses.] Dendrochronologia 7: 145-157. Diffuse-porous species When working with diffuse-porous wood, where vessels are usually uniformly distributed throughout the growth ring, Powder methods may not be helpful to aid in ring boundary recognition. Some specific techniques follow which may be of help for other species: 1. Liriodendron tulipifera: Progressive sanding and polishing up to paper number 1200. If this fine sanding is still not enough then the sample could be stained with phloroglucinol (in a water-chloride acid solution), but other stains for lignine could also be used (such as safranine). The samples should again be polished after the staining process using 800 to 1200 grit. A better contrast can then be obtained by rubbing chalk onto the surface. (Ignacio Garcia) 2. Yellow-poplar: After sanding to paper number 600, fine shavings can be sliced off the core. There is now a choice of looking at either the new surface or the shavings themselves. For most dendrochronological purposes the study of the new surface at standard magnifications (i.e. 20-30x) should be enough to observe ring boundaries. However, with yellow-poplar, unclear ring boundaries can be observed by studying the shavings at high magnifications (i.e. 400x). At this level of magnification, the ring boundary can be seen by a band of undifferentiated parenchyma cells. This technique is used by wood ID specialists (Thomas Schuler). The following section has been provided by Geoff Downs of the CSIRO Division of Forest Products and is from an article entitled "Sampling plantation eucalypts for wood and fibre properties". This section is specific to sample preservation for Silviscan analysis. The major issues in sample storage and preparation are as follows. 1. Prevention of fungal degradation 2. Minimising the change in wood cell dimensions from those that exist in the living tree 3. Clear and logical sample coding Fungal degradation. As soon as a wood sample is removed from a tree, fungal spores will be present along the surface, and can do considerable damage in a short period of time. The whole sampling procedure should be worked out step by step before venturing into the field. On no account should wood samples, discs or cores, be left for more than 2 days at ambient temperature in the green state. Fungal hyphae can spread rapidly through the wood, altering the wood chemistry and degrading the cell wall. The prevention and/or minimisation of fungal growth can be accomplished in several ways. Disks can be wrapped in plastic bags and stored in a freezer, until further preparation is required. Alternatively the disks can be stored in 4% formalin. However the treatment of samples with chemicals needs to be considered in the light of the analysis of the samples. Ultimately the samples will need to be prepared for analysis, and at this stage care is needed to minimise dimensional changes. Minimising dimensional changes prior to analysis. In the rapid assessment methodology that is being developed by the CRC-HFPS, it is necessary to dry the wood to an air dry state for analysis. Air drying plantation eucalypts directly from the green condition will result in considerable checking and collapse, making cell dimensional analysis meaningless. However for NIRA this is not an issue. Work done at the CRC-HFPS (Downes et al., unpubl.) has found that green wood samples should be placed into 100% ethanol as soon as possible after sampling. This helps to preserve the wood by preventing fungal growth, and facilitates the drying process. Large samples (disks) can be stored in this way for extended periods of time. Storage in ethanol will however result in the removal of some extractives from the tissue. For micro-structural analysis this is unavoidable and ethanol has been chosen in part for its mild action as a solvent. To dry the sample and avoid the problems of collapse and checking during drying, all water in the wood needs to be replaced with ethanol. Increment cores could be placed in ethanol immediately upon removal from the tree if appropriate containers are taken into the field. Ethanol should be replaced at least 3 times over the next 2 weeks. Prior to air drying the cores should be refluxed in ethanol over a six hour period, to complete the water removal process. Cores can then be air dried and stored. This treatment will result in minimal dimensional changes between the green and dried conditions. The larger the sample the greater the time needed to replace water with ethanol. Storage in ethanol will result in the extraction of some polyphenols from the wood, and ethanol may not be removed completely by air drying. Similarly water storage will result in the extraction of polyphenols and low molecular weight carbohydrates. Hot water is a common solvent and will extract more than hot ethanol. However the comparative extractive abilities at ambient temperature is undetermined. Extractive ability is linked to the polarity of the solvent. Less polar solvents like petrol will minimise extractive loss. Acetone is a common solvent of medium polarity. However for eucalypts ethanol is preferred. Sample coding The importance of sample coding cannot be over emphasised. When samples are analysed, any uncertainty about the origin of the sample will cause uncertainty in the whole project. Sample coding must meet the following criteria: 1. It must be permanently written on the wood surface. 2. The writing must be legible. 3. The code must contain sufficient information such that its origin is beyond doubt. There are several brands of pencils that are suitable for this purpose. The Staedler copying pencil, is available from specialist stationery stores and will write on wet surfaces. Similarly the Aquarellable pencil does a similar task. Lumber crayons are also useful, as are Tag pens. The use of plastic labels (e.g. Dymo labels, Tytags) stapled onto disks and billets is adequate. An alternative protocol has been used by the CRC-THF. Sample codes are written onto Tytags, which are stapled to the tree to be sampled. The person taking the core removes the tag and fastens it to the core by elastic bands (1 each end). The core is then placed in the appropriate storage facility. In this way the chance of wrongly labelling the core, or sampling the wrong tree is minimised. Some form of cross checking the sample coding is invaluable. A copy of the master sheet of sample codes should be kept and sent with the samples for analysis. The importance of clear and accurate sample coding cannot be over emphasised. Q9.4: How do I get resin off my cores? {top} There are a number of approaches to removing resin: * The cautious application of heat will liquefy resin and bring it to the surface where it can be wiped away in the instant before it solidifies again. Repeat until resin ceases to come to the surface of the sample. This is best for relatively small areas. (Malcolm K. Cleaveland) * A solvent (2 ethanol: 1 benzene) in an ultrasonic bath can be used. (Malcolm K. Cleaveland) * Use very fine steel wool to burnish the resinous surface some time after it has been initially smoothed. The resin will be wiped out of the cells, leaving a good-as-new sample. (Jim Parks) * Soak cores overnight in ethanol to remove the resin (Henri Grissino-Mayer) * A two bath process, with first hot tap water, which gets rid of lots of stuff, then hot cyclohexane/methanol (70:30). By setting it up in a siphon/soxhlet type of arrangement, it can run largely untended for a few hours, and so takes very little operator time. (Ian Campbell) Q9.5: Twisted cores? {top} Twisted cores is a common problem which probably has plagued most dendrochronologists at one time or another. Why it occurs is something for debate. However, in general, the use of sharp corers should diminish ones chances for twisted samples. It has also been suggested that coring after the growing season (i.e. in Autumn), may also help. The degree of twisting can also vary from just slight twisting along the whole core to a 360 degree twist in just a few centimetres. Undoubtedly there are many techniques to untwist cores, but below are a few that have proved successful: 1. First, rehydrate the twisted core by soaking it in water overnight. Then untwist it by hand, being careful not to break it by going to fast. The key goal at this point is to allow the sample to dry again so that it can shrink but not re-twist. To accomplish this goal, attach clothes pins (or something similar) to the side (radial view) of each end of the untwisted core, and then set a flat, moderately heavy object (e.g. a hardbound book) on the clothes pins and let the core dry overnight. (Paul Sheppard) 2. Soak the core in a solution of urea (1:1 with water, by weight), let it dry, and then steam it. The core should untwist easily with no breaks. This technique is described in Joy Youngs thesis (University of Arkansas: pyoung2 at unix1.sncc.lsu.edu) and a short paper will be submitted to the TRB shortly. 3. Twisted cores can be relatively easily untwisted over a "Steam Jet Generator" or to most of us, a boiling Kettle. (Peter Brown) ---------------------------- 10. More Information Q10.1: Where can I find out more? {top} If you haven't found an answer to your question here, then a message to the ITRDB forum is indicated (Q2.1, 2.2). Please mark you subject line with "Request:.." (Q0.3) If you are really desperate, you could also search through the ITRBD forum archive files. If you use the "get" command (Q2.2) to get all the archives, and you have a mail application that allows string searching, then you should be able to track down any occurrences of the subject/string that you seek. ---------------------------- 50. Glossary Q50.0: Do you have a glossary of tree ring terms? {top} As yet, this Glossary section is EMPTY. We are presently trying to organise a FAQ glossary with Hal Fritts, Michele Kaennel and Fritz Schweingruber, but this will not be ready until later this year.