Optional page title

Optional page description text area...

Header Content Region

Insert text, image or banner ads here, or just delete this text and leave this area blank!

Eastern Hemlock

Latin name:
Tsuga canadensis

Extracted from a waterfront pier near Wilmington, Delaware, the tree used to make this portion of the pier
actually came from a forest located in central Pennsylvania. The outermost tree ring dates to the late 1830s.

Giant Sequoia

Latin name:
Sequoiadendron giganteum

A close up of numerous fire scars on a giant sequoia cross section from Sequoia National Park in California, dating back well prior to A.D. 1000. Look closely! Can you find the sad bearded face cradled by his hands, as if he was crying?

Douglas-fir

Latin name:
Pseudotsuga menziesii

This photo shows the tree rings from a beam extracted many years ago from a pueblo in northeastern Arizona. The section shows many false rings and many micro-rings, suggesting this tree may have been growing in a marginal environment.

Ponderosa Pine

Latin name:
Pinus ponderosa

Close up of tree rings of a ponderosa pine collected at El Malpais National Monument in New Mexico, USA, showing tree rings centered around A.D. 1400. Notice the variability in ring widths indicative of sensitivity to year-to-year variation in precipitation.

Douglas-fir

Latin name:
Pseudotsuga menziesii

Perhaps my most requested image of tree rings, obtained from a small Douglas-fir growing in the Zuni Mountains of west-central New Mexico by my colleagues Rex Adams and Chris Baisan. Not very old, but has some of the most beautiful rings of all my displays!

White Oak

Latin name:
Quercus alba

Oak cores from the Hoskins House in Greensboro, North Carolina, site of a famous battle during the Revolutionary War. The house was built from trees cut in 1811 to 1813, not cut and built in the 1780s as the historical agency had hoped.

Ponderosa Pine

Latin name:
Pinus ponderosa

This ponderosa pine once grew at El Morro National Monument in New Mexico, USA, and was cut many years ago. Once you get up close to the stump, you can see a very old scar from a fire many hundreds of years ago that scarred the tree when it only about 12 years old!

Bahamian Pine

Latin name:
Pinus caribaea var. bahamensis

We collected many cross sections of Bahamian pines that had been cut for an industrial park on the island of Abaco, but the rings are very difficult to date! Many false rings, and the pine appears to terminate tree growth during the dry season.

Longleaf Pine

Latin name:
Pinus palustris

This cross section was one of many that came from an old crib dam across a creek that was exposed after a modern dam broke in Hope Mills, North Carolina in 2003. Such sections from old-growth longleaf pines are very rare and provide information on climate back to AD 1500!

White Oak

Latin name:
Quercus alba

Sometimes you don't have to look far to find beauty in wood, and sometimes it may not be a living tree! After an oak tree was cut a year or two before this section was obtained, decay fungi had already set in, beginning to break the wood down to its basic elements.

Southwestern White Pine

Latin name:
Pinus strobiformis

I collected this fire-scarred pine on Mt. Graham in southern Arizona in fall 1991, and it remains one of the best examples of how we can determine the season of fire by looking at the position of the scar within the ring.

Bristlecone Pine

Latin name:
Pinus longaeva

Bristlecone pines have become one of the best proxy records for those who study the history of volcanic eruptions because the cool temperatures caused by these eruptions create "frost rings" that form when the cells implode from the cold.

Eastern Redcedar

Latin name:
Juniperus virginiana

Many well-preserved eastern redcedar sections have been recovered from prehistoric sites in eastern Tennessee, and they have more than enough rings to date, but we don't have a long enough living-tree reference chronology to overlap with them!

Red Oak

Latin name:
Quercus rubra

Oak is by far the most common genus we find in the many historic structures we date using tree rings in the Southeastern U.S. The genus has good ring variability and rarely has problem rings. This section came from a historic tavern in Lexington, Virginia.

Sugar Maple

Latin name:
Acer saccharum

Maple, birch, beech, and basswood are all examples of hardwood species that form diffuse porous wood, meaning that the ring contains many small-diameter vessels all through the ring. Identifying the ring boundary on this wood type is a challenge to tree-ring scientists.

Live Oak

Latin name:
Quercus virginiana

Live oak is an example of an evergreen oak, which is not common within this genus. As such, the wood is semi-ring porous and the rings are very difficult to see and date. Ring growth is also very erratic, not forming the concentric around the tree that we require.

Douglas-fir

Latin name:
Pseudotsuga menziesii

These cores were collected on Mt. Graham in southern Arizona and show a major suppression event beginning in 1685 when missing rings became evident, followed by many micro-rings. This suppression was caused by a major wildfire in 1685!

Ponderosa Pine

Latin name:
Pinus ponderosa

I find it amazing what trees can record in their tree rings! Here we see a cross section of a pine that was damaged by a major flood in the year 1945 in the Chiricahua Mountains of southern Arizona. Notice the reaction wood that formed afterward.

Pignut Hickory

Latin name:
Carya glabra

Sometimes gray-scale imagery helps define tree rings when measuring. Although classified as "ring porous" species, the rather ill-defined tree rings in hickory tree species form large earlywood vessels and smaller latewoood vessels.

Subalpine Fir

Latin name:
Abies lasiocarpa

Decay has set in on the tree rings of this dead and downed subalpine fir that once grew on Apex Mountain in British Columbia, Canada, but the tree rings can still be measured and crossdated despite this!

White Fir

Latin name:
Abies concolor

We found a beautiful fire scar on this white fir that was used to build a cabin in the Valles Caldera of New Mexico. Thought to have been built in the early 1900s, we instead found the cabin was built form white fir and Douglas-fir trees cut in 1941.

Overcup Oak

Latin name:
Quercus lyrata

These oak cores were collected in northeastern Arkansas to investigate a change in the hydrologic regime of a wildlife refuge beginning in the 1990s. We found that trees at this site experienced a major disturbance event in the 1960s.

Western Juniper

Latin name:
Juniperus occidentalis

Near Frederick Butte in central Oregon, we discovered an unusual stand of western junipers that had the most unusual lobate growth forms we had ever seen. This site yielded a drought-sensitive chronology dating back to the AD 800s!

West Indies Pine

Latin name:
Pinus occidentalis

Above 3000 meters on the highest peak in the Carribean, we found an entire forest of these pines, many with fire scars, living on a steep rocky slope. The forest looked more like the dry ponderosa pine forests of the western U.S.

Whitebark Pine

Latin name:
Pinus albicaulis

Whitebark pines growing in the northern Rockies of the western U.S. can grow to be over 1,000 years old, but the species is slowly being decimated by the introduced white pine blister rust. Many of these ancient trees are now dead with ghostly white trunks.

Shagbark Hickory

Latin name:
Carya ovata

Curiously, tree-ring scientists rarely analyze some of the more common hardwood species in the eastern U.S., such as this hickory, perhaps because such forest interior trees may contain a weak climate signal necessary for crossdating.

Virginia Pine

Latin name:
Pinus virginiana

Blue stain found in many sections of dead pines (both in the western and eastern U.S.) is caused by a fungus carried by a pine beetle. The fungus spreads into the phloem and sapwood of living and dead pines, sometimes creating stunning patterns!

Pinyon Pine

Latin name:
Pinus edulis

Burned sections of pinyon pine are commonly found in archaeological sites in the southwestern U.S. These sections can be carefully broken or surfaced with a razor to reveal the ring structure inside to assist in dating the years of construction of the site.

Red Spruce

Latin name:
Picea rubens

Conifers in the highest elevations of the Appalachians of the eastern U.S., such as this red spruce, don't experience wildfires very often, but when fires do occur, they can create numerous fire scars even in this fire-intolerant species. Notice the growth release!

White Spruce

Latin name:
Picea glauca

This tree was located in the Canadian Rockies on the toe slope of an active avalanche path. The scar was created by a debris flow or snow avalanche which struck the tree, killing a section of the living tissue. The avalanche can therefore be dated to its exact year!

Engelmann Spruce

Latin name:
Picea engelmannii

I worked considerably in the spruce-fir forests of southern Arizona in my earliest years in dendrochronology, and learned that trees with limited sensitivity can provide a vast amount of information on the history of these forests.

Pondrosa Pine

Latin name:
Pinus ponderosa

The lava flows of El Malpais National Monument in New Mexico contain vast amounts of remnant wood, mostly ponderosa pines such as this sample, and the tree rings on these samples go back nearly 2000 years! Notice the year AD 1400 on this section.

Chestnut oak

Latin name:
Quercus montana

In the southeastern U.S., hardwood species are often scarred by wildfire. Most often, this also will cause considerable decay in the sample, but this oak had several well preserved fire scars, suggesting fire was common in these drier, lower elevation sites.

Pondrosa Pine

Latin name:
Pinus ponderosa

I originally sampled this stump in 1991 for its fire scars, located in El Malpais National Monument of New Mexico. I found it again 20 years later and was happy you could see the tree rings and fire scars clearly! It had originally been logged in the 1930s!

small portfolio1 small portfolio2 small portfolio3 small portfolio4

 

 

 

get in touch

Thank you for your feedback!

Please tell me what you think about my web site. What did you like or not like about them? Were they useful and educational? In what areas could I improve these web pages? I take your comments seriously! Simply contact me by e-mail (use the link at the top) and tell me what you think.

Current Feedback Page
Feedback Archive Page 9
Feedback Archive Page 8
Feedback Archive Page 7
Feedback Archive Page 6
Feedback Archive Page 5
Feedback Archive Page 4
Feedback Archive Page 3
Feedback Archive Page 2
Feedback Archive Page 1

  1. "I cruised around your tree-ring home page and found some interesting stuff - good job."
    - Dana Perkins, Stanley, Idaho

  2. "I have seen the site that you maintain on the internet for Tree-Rings and it is very impressive."
    - Tomas Martin, McGraw-Hill Encyclopedia of Science & Technology

  3. "My daughter is bringing in a slice of the trunk of an apple tree that fell during Hurricane Floyd for show and tell to her 1st grade class this week (I planed and sanded one side of it, and applied some tung oil, to highlight the rings - maybe there's a better way but it looks nice). Your site helped me understand and explain to her the basics of "reading" tree rings - and I found the information to be extremely interesting. Many many thanks from Molly and me."
    - Bob Johnson

  4. "Have a look at the Ultimate Tree Ring Web Pages which has links to everything you every wanted to know about dendrochronology."
    - Barbie Panther, Monash University, Australia

  5. "Browsing your excellent web pages. You are doing a great job. Continue with your good work, Henri."
    - Richard L. Holmes, Tucson, Arizona

  6. "Very nice website!"
    - John Pearson, Iowa Department of Natural Resources, Des Moines, Iowa

  7. "Thanks for all this pioneering work! Come to Michigan and we will take a tree-ring tour."
    - Robert R. Bloye, Forestry Department, Michigan State University

  8. "Thanks for your tips."
    - Alejandra Florio, Universidad de Bs.As., Argentina

  9. "Interesting and informative! Thanks!"
    - Amy Parsons, Burlington, Ontario, Canada

  10. "I wanted to thank you again for your website...it was very helpful in determining what to purchase. Also, thanks for all the pointers you have given me in setting up the lab here."
    - Deanna McKay, Department of Geography, Colgate University

  11. "I am very impressed with your tree-ring site and the landforms and Geog 1112 sites. Do you have other sites? I am an Earth Space Systems teacher (grades 9-12, small rural high school, pop. 1200). I would like to include your site in my Home Page. Is this okay with you? Also, I am helping NASA develop a new Teacher site. Could we also include you there? When it is up and running I will let you know. Hope to hear from you soon."
    - Robbie D. Robinett, Ridgely, Maryland

  12. "Thanks for maintaining this cool web page and making all this information available."
    - Laurie S. Huckaby, Fort Collins, Colorado

  13. "As part of my Environmental Technology program I am writing a paper on Dendrochronology. A great deal of my information was taken from your wonderful web pages."
    - Patricia A. Marlowe

  14. "Great web site."
    - Elwin C. Robison, Kent, Ohio

  15. "My sincere thanks for your response concerning dendrochronology. I appreciate your efforts and your time."
    - Paul Beckstrand, Pinehurst, North Carolina

  16. "Thanks for a great site and so much information in a understandable format. I am a fire captain at Santa Barbara fire station 7 and firescapes demonstration garden."
    - John Culbertson, Santa Barbara, California

  17. "Thanks for your continuing dedication to the discipline."
    - Donald J. McGraw, Associate Provost, The University of San Diego

  18. "First let me say that your tree-ring page is a marvel and a tremendous help to me and others connected with forests."
    - George Zimmerman, Environmental Studies Program, Richard Stockton College of New Jersey

  19. "Peter Brown recomended your web page, and it's been very helpful. Thank you."
    - Will Wieder, Colorado College

  20. "Your web page is a great resource for tree ring research!"
    - Tim Boyle, California State University Northridge

  21. "I have seen your web pages and they are very helpful and interesting."
    - Abigail Knight, Manchester Metropolitan University, United Kingdom

  22. "Your website has been a great deal of help to me. Thanks for your time and the great website."
    - Jennifer Gibson, National Park Service-Whiskeytown, Fire Management Office

  23. "How much you accomplish is unbelievable. I accessed your web site this morning and once again you have expanded and refined it. I'm sure the site is invaluable to many others as it was to me."
    - Anne Johnson, Honaunau, Hawaii

  24. "Thanks, this is very helpful to our work on the global warming campaign here at the National Environmental Trust in D.C. (with field reps doing local press events in 27 states)."
    - Peter L. Kelley, National Environmental Trust, Washington, D.C.

  25. "Very good Web site... I want to thank you in advance."
    - Mim A. Romero, Las Vegas, Nevada

  26. "I have visited your website - it's great."
    - Mark Pretti, Ramsey Canyon Preserve, Hereford, Arizona

  27. "Great information! I am a structural engineer evaluating century-old wood structures. I needed to find increment core tools for purchase, and learn some useful tips for my type of field work (inside abandoned buildings in the middle of downtown St. Louis - it's more challenging than you might think). I really found the tips on straws for cores and core mounting tips to be useful. As soon as I get my bore tool, I'll be trying these tips out. Thanks."
    - Jim Taylor, St. Louis, Missouri

  28. "Thank you for a fabulous set of web pages and links! I've spent the better part of two days reading your pages and following the links. Wonderful stuff!"
    - Pat Murphy, Exploratorium Science Museum, San Francisco, California

  29. "I recently visited your home page and found a wealth of information."
    - John Wallace, JE Fuller/Hydrology & Geomorphology

  30. "Very good information for educators."
    - Elva Cruz, Puerto Rico

  31. "Your web page is so all encompassing that it hard to imagine that you have time for anything else."
    - Anne Johnson, Honaunau, Hawaii

  32. "I congratulate you on the excellent work you have done in making so much information available on the web. Keep up the good work."
    - Randy Boggess, Texas

  33. "Excellent Web Site; only had time to scratch the surface but will be back!"
    - Andy Parks, Faculty of Forestry, University of Toronto, Canada

  34. "Thanks, best wishes and congratulations for the web page."
    - Horacio Gilabert, Universidad Católica de Chile, Santiago, Chile

  35. "I really enjoyed your web site! It was certainly the most comprehensive and informative look at dendrochronology that I have seen."
    - Jon Shepherd, Florida Institute of Technology

  36. "Let me express my appreciation to your web pages and joint databases. I use it almost every day (more frequently than a borer)."
    - Tomas Tichy, Department of Botany, Charles University, The Czech Republic

  37. "Thank you for your help. You have the best Web Site I have seen. Everything works."
    - Woodrow L. Antle, Plantation, Florida

  38. "Great web site!"
    - Max Creasy, Klamath National Forest, California

  39. "I saw your website and it looks really good. Your web page was quite inspiring. Thanks for any help you can provide."
    - Robert Borhi, British Columbia, Canada

  40. "Interested in "The Principle of Aggregate Tree Growth?" or want to find out why fire is beneficial to some forests? You’ll find this information and so much more here at the definitive resource of dendrochronology (tree ring study). Don’t miss the great pictures with quiz questions and answers."
    - San José State University Botany Web Site

  41. "First of all, excellent web page! I am just getting interested in dendrochronology, which I have found to be a fascinating subject."
    - Patrick Spears

  42. "I've just been browsing in your dendrochronological page, it's quite impressive, and overwhelming. You are to be congratulated."
    - David Sims, Internet Content Writing & Editing

  43. "Very useful web page, congratulations - deserves an award!"
    - Rosa Richards, England

  44. "I just discovered your web page on the internet while searching for infomation on dendrochronology equipment. What I saw in my quick browsing of your site was quite helpful."
    - Alan Stam, Capital University

  45. "I am helping set up ecology activities at a Girl Scout Camp in Singapore the end of this month. One of the badge activities is for tree ring counting. Thanks. I think your web site is great -- very easy to access and use."
    - Marlene M. Accardo, Singapore

  46. "Thanks for creating such an interesting and accessible site! It is clear that you are highly knowledgeable and a gifted educator."
    - Alice, Gloucester, Massachusetts

  47. "Thank you for maintaining your web site; I'm truly grateful."
    - Risa Madoff, New Mexico State University, Las Cruces

  48. "Your web pages are looking as good as ever. Keep up the good work."
    - Matt Bekker, University of Iowa

  49. "I enjoyed your web page a lot and plan to use the information in a general paleoclimatology class I will be teaching next year."
    - Adina Paytan, Scripps Institution of Oceanography, La Jolla, California

  50. "I really really enjoyed your site, and bookmarked it for future viewings -there is so much information, I don't have time for it all at once! Our son is doing a science project on tree ring dating, and it's been fun helping him. Anyway, your site carries a wealth of information! Thanks in Alaska."
    - Connie Tonsgard, Alaska

  51. "Congratulations on your useful and really exemplary Tree-Ring Web Pages."
    - Klaus-Peter Kelber, Mineralogisches Institut, Universitaet Wuerzburg, Germany

  52. "Thanx for spending the time to prepare and maintain such a well-thought site. It has been an excellent resource for my daughter's science fair project. Unfortunately, the plethora of articles and links has proved to be a great distraction."
    - E. Kusko, Hopewell Junction, New York

  53. "I am glad to see that there are some good sites in this field of study."
    - Susan, Pembroke Pines, Florida

  54. "Thank you so much for the dedication you've poured into your dissertation, the software, and the web pages. You make the tools wonderfully user friendly and truly inspire interest in dendro work."
    - Joseph Donnegan, Department of Geography, University of Colorado

  55. "After having seen many badly designed pages, it was refreshing to find your page. Nicely organized with graphics that don't interfere with the information (one of my pet peeves). I teach internet classes and I think I'll use your page as an example of good design. You provide your credentials and you've chosen quality information sites. Good Job! You get an A+."
    - Pamela Posz, Reference Librarian, Sacramento City College, California

  56. "Your website is very informative and has great links."
    - John Paul Roccaforte, School of Forestry, Northern Arizona University

  57. "What a find! I am an archaeological conservator in Atlanta, doing private and contract work. This homepage is great!"
    - Katherine Singley, Atlanta, Georgia

  58. "All I can say is, "WOW" - what a terrific resource you have created!"
    - Jill Minar, Crafton Hills College, Yucaipa, California

  59. "Your website is fantastic - I will be using it with a bunch a second and third graders later this spring. You have a ton of great pictures and some wonderful facts. Thanks for providing this wonderful resource!"
    - Jim Reed, Media Specialist, Brainerd Public Schools, Minnesota

  60. "Dr. Ferguson's findings were the impetus for us to write "The Ancient Bristlecone Pine Forest," a guide put together for laymen. In the process of updating the book, I rely on your comprehensive site for help. It boggles my mind how you find time to keep up your useful and informative site."
    - Anne Johnson, Honaunau, Hawaii

  61. "I want to thank you for all the work that you do with the web pages for the dendrochronologists of the world."
    - Luciana Carotenuto, Italy

  62. "I am a Junior Girl Scout Leader in the Buffalo, NY area. This information will be very helpful for our girls to complete their Ecology Badge. The information and pictures were fantastic. I truly appreciate your time and effort. I never knew so much can be learned about the environment from the study of tree rings (Dendrochronology - a knew term for me). Thanks again!"
    - Linda Colkitt, Troop 1159, Tonawanda, New York

  63. "The pages were useful for writing my introduction to the tree rings/weather lab. It must be a big job creating and maintaining the site! Thanks from the geology students at X!"
    - Laurie Munro, St. Francis Xavier University, Canada

  64. "Great links and thorough bibliography, I've very much enjoyed this page."
    - Taylor McKinnon, Flagstaff, Arizona

  65. "I am a docent at the Arizona Sonora Desert Museum. One of the kits I enjoy interpreting for visitors is the tree ring kit. Your web site has given me a wealth of resources which I will share with other docents who also enjoy doing this kit. So thanks for your help. I am sure that I will be going back to your web page now that I have found it."
    - Molly Tiss, Arizona-Sonoran Desert Museum, Tucson, Arizona

  66. "... an excellent website..."
    - Michael Feller, Forest Sciences Department, University of British Columbia, Canada

  67. "This is a great reference page. I am doing a lab on the interactions of tree rings and climate and I am looking for some background info on tree rings."
    - Laurie Munro, Antigonish, Nova Scotia, Canada

  68. "Great job, very nice to see."
    - Matthew Arsenault, University of New Hampshire

  69. "I found your site to be a great source of information, and interesting as well. Great pictures!"
    - Angela Cunningham, Baylor University, Texas

  70. "I read your tree-ring pages with interest and pleasure."
    - Georg Wendland, Dresden University of Technology, Germany

  71. "I enjoyed your site. I have been cutting down some spruce trees for heating. The one that I take are bug killed... I found your site by typing in (tree rings) and it was very helpful. Thank you."
    - Bob Langendorfer, Alaska

  72. "Henri Grissino-Mayer’s web pages dedicated to dendrochronology are excellent introductions to the methods and goals of tree-ring dating."
    - Colorado Heritage Education Resource Guide

  73. A great site... just returned from the Dendroecological Lab Week in Freiberg where there was a lot of coverage about this site."
    - Joanna Forbes, Forestry Commission, Scotland

  74. "Your web page is excellent."
    - Helen Whiffen, The University of Georgia, Athens

  75. "I found you from a write-up in the August issue of Science ... I am hoping to use the site for my introductory biology majors course to liven up the part on trees (xylem and phloem and rings, oh my!)"
    - Dr. Penny Bernstein, Kent State University, Stark Campus

  76. "Lots of great information here."
    - Kevin Bonine, University of Wisconsin - Madison

  77. "I have been looking at your web site lately and I think it's really cool. I like the question part because I'm trying to learn the answers."
    - David Dowdy, 4th grade, Albuquerque, New Mexico

  78. "I wanted to say that your site is GREAT - very informative."
    - Jennifer Rubbo, National Wetlands Center, Lafayette, Louisiana

  79. "Probably the best website available for tree-ring (dendrochronology) research. Includes images, facts, and links to other highly useful resources."
    - Willamette University Library Biological Resources, Oregon

  80. "Great page, the searchable bibliography was especially useful."
    - Kieran Suckling, Tucson, Arizona

  81. "I'm amazed at the extent of the resources and ease of operation that your page provides! I used your searchable database to look up a number of papers on the matter. ... I will be spending a lot of time on your page in the near future. Thanks so much!
    - Alex Kalejs, Baltimore Ecosystem Study, Maryland


  82. "I am a seventh grade science teacher in Kansas. I am attempting to implement dendrochronology into my class. (We do have trees in Kansas.) Your web sight is the best! It has been very helpful."
    - Gary Pinkall, Kansas

  83. "On this definitive site for researchers in the field of dendrochronology, Henri Grissino-Mayer of Valdosta State University, Georgia, has recently added a useful and practical list of tools for conducting field and laboratory research. In addition to a hypertext-linked list, the site includes helpful tips to help make the task of tree-ring dating easier. Back at the "Ultimate" web page, users will find many interesting facts and beautiful images of ancient tree cross-sections, complete with question and answers."
    - University of Kentucky Library Resources, Lexington, Kentucky

  84. "Your website seems to have grown again since my last visit! The new "Introduction to Crossdating" from Dr. Paul Sheppard at the Tree Ring Lab is a great addition."
    - Leonard Miller, Ancient Bristlecone Pine Website, Sonoma County, California

  85. "A very good introduction to the theory and method of dendrochronology. Recommended."
    - Prof. Philip Groth, Anthropology Web Hawg

  86. "I was just looking for info on forestry and mining and ended up here! I really like your page! And will come back to look at it further. Keep up the awesome work!!"
    - Denise Jindra, Tumbler Ridge, British Columbia, Canada

  87. "I do not normally like computers very much but this is great! I will definitely come back and use this site in the future. I am just starting to learn dendrochronology and find it fascinating with much potential."
    - Talya Bagwell, Landscape Archaeology, University of Sheffield, United Kingdom

  88. "That's great!!! Exactly what I was looking for... I need this information so much. Thank you."
    - Marcin Makocki, Colegio de Postgraduados, Montecillo, Mexico

  89. "I really liked your site and intend to spend some more time with it in the future. I am working on an exhibit and would like to use tree rings to help people connect a little more to their local history. Thanks."
    - Eames Demetrios

  90. "Great job!!! We needed somebody to put it all together--thanks!"
    - Pater Kakos, Navajo Nation Historic Preservation Department

  91. "What a great site! I even know where Valdosta is; spent my boyhood there... Thanks for your help in this web page!"
    - Jon Monson, Greely, Colorado

  92. "Very much appreciate your website - a wealth of information to be had."
    - Lennart Holmquist, Neuchatel, Switzerland

  93. "I just found out about your tree-ring website...it was mentioned in SCIENCE. There is so much to explore that I will have to come back many times to see it all."
    - Susie Welch, New Mexico Bureau of Mines and Mineral Resources, Socorro, New Mexico

  94. "Thanks for your good work -- and fascinating web page."
    - Gary Garber, Phoenix, Arizona

  95. "Your web pages are an amazing resource."
    - David Wager, Department of Forest Resources, Utah State University

  96. "Your web site and data base intrigue me. Thank you for putting it together."
    - Karl von Oppen

  97. "Thanks for all of the clearly-presented and easy to understand information. I used your site researching in advance of a Climatology class field trip to the White Mountain Research Station; now I'm putting together a 15 minute talk on the topic for another course. I was an undergrad waaaaay before the advent of PC's and the Web; now I'm glad I waited nearly 20 years to start grad school... 'cuz with stuff like your work out there, life is MUCH easier!"
    - Tina M. White, California State University, Northridge

  98. "What an amazing amount of work you've done. How do you have a life? Your pages are tastefully and informatively presented. I'll be spending a lot of time here. Thanks for your efforts."
    - Ellen Anderson, USDA Forest Service, Juneau, Alaska

  99. "Henri D. Grissino-Mayer's environmental web page on tree rings is a great example of what one person, who is an expert in an important field in environmentalism, can accomplish. His site begins with complete definition of dendrochronology, then shows how it works, how to find more information, and how to get a job in the field. He even shows you what tools you'll need (and where to get them) if you want to experiment with the facts locked up in tree-rings yourself. Our ancestors didn't keep very good records on the environment, but trees did. Take a lesson on Earth's history from a well-thought out website."
    - Frank J. Regan, Environmental Site of the Week Award

  100. "Thanks for a most informative site."
    - Bill Cibula, Picayune, Mississippi
slide up button
Google Search Helps Support These Web Pages!