From: Pederson, Neil To: [email protected] Sent: Tuesday, December 22, 2009 11:47 AM Subject: Re: oldest counted white oaks - a synthesis
Hi Jean-Luc, apologies for not writing earlier as i figured you were mostly interested in white oaks of Europe. in eastern North America (ENA) we've not yet broken 500 yrs. the oldest Q. alba comes in at 464 yrs. if we could relocate that tree today and it was living today as it was when cored in the early-1980s, it would be approaching 500 yrs. there are other white oak species in ENA whose maximum documented age is in the upper-300s and lower-400s, including Q. muehlenbergii, Q. montana and Q. stellata. the oldest Q. bicolor is currently 285 yrs. however, it hasn't been cored much, so i would bet one could be found in the upper-300 to lower-400 yr age range. to see a list of the oldest and others near the max age, go here: http://people.eku.edu/pedersonn/oldlisteast/ neil ________________________________________ From: ITRDB Dendrochronology Forum [[email protected]] On Behalf Of Guillermo Gea Izquierdo [[email protected]] Sent: Tuesday, December 22, 2009 5:56 AM To: [email protected] Subject: Re: oldest counted white oaks - a synthesis Dear Jean-Luc, even if you might not include it as a white oak, you could be interested to know that we have just cored a Q. pyrenaica tree in NorthWestern Spain which had 420 rings (we did not reach the pith; some other trees older than 350 years were cored in the same stand), and a dbh of 72 cm. This age is not surprising, but still it is nice to find (and count rings) such old individuals. On the other hand, we crossdated (to the pith), one 93 years old Q. ilex individual, of dbh 68 cm and a mean crown radius of more than 14 m. No need to say that similar diameters in the same species seem to go far over 300 years (“ring” counting, not so easy to crossdate these old evergreen oaks and also not so easy to find old individuals without rot, similar to other oaks). Cheers. Guillermo --- Guillermo Gea Izquierdo Dendro Sciences-Tree Physiology Group Swiss Federal Research Institute WSL Zürcherstrasse 111 CH-8903 Birmensdorf-SWITZERLAND Email: [email protected]<mailto:[email protected]> [email protected]<mailto:[email protected]> Phone: +41 44-739 2392 Fax: +41 44-739 22 15 web: http://sites.google.com/site/guigeiz/ http://www.wsl.ch/forschung/forschungsunits/dendro/treephysiology/index_EN --- De: ITRDB Dendrochronology Forum [mailto:[email protected]] En nombre de Dupouey Jean-Luc Enviado el: December-21-09 9:43 PM Para: [email protected] Asunto: oldest counted white oaks - a synthesis Dear colleagues, I received a couple of answers to my enquiry about the oldest counted white oaks (section Quercus of the Quercus genus). I thank all the contributors. Here is the current stage of my knowledge. Not surprisingly, the winner is… a dead oak! The oldest was cut in Spessart (Germany) in 1957, and the heart dated by Bruno Huber and Bernd Becker at AD 1366, giving an age of 588 years. Not so bad! I thank Michael Friedrich for this information. He does not know if it was Q. petraea or robur. I was primarily interested in white oaks from Europe (Quercus petraea, robur, pubescens…) but I received an information from Dan Griffin about a Quercus douglasii (endemic from California, white oak as well) he studied and which displayed 555 rings. It was also a dead tree. It is not (yet?) included in Peter Brown’s OLDLIST (http://www.rmtrr.org/oldlist.htm) which focuses on the oldest trees, mainly of North America. David Brown counted 512 rings in a stump of the famous Sherwood Forest (UK). Once again, an undifferentiated Q. petraea or Q. robur tree. That is all for dead oaks above 500 rings. Not so many. What about living oaks? The living oak with the largest number of counted rings is a Q. petraea tree from Sherwood Forest, displaying 470 rings in 1981. David Brown cored and counted it. But we do not know if it is still living today. In 2001, Chris Lavers counted 403 rings on a core from an oak of the same forest (unidentified species). In 2004, Krzysztof Ufnalski counted 441 rings in a Q. petraea tree from the Drawienski National Park (NW Poland). In the same part of Poland, in the Wolin National Park, Tomasz Wazny counted 433 rings in 1986 on an unidentified oak (Q. petraea or robur, of course). In both cases, these stands seem to contain many trees in the range 400 to 500 years. Thus, Sherwood in UK and NW Poland are, up to now, the places with the oldest living oaks in Europe. That is all for living oaks above 400 years. Once again, it is not so many. In Switzerland, Patrick Gassmann reported a 453 years sequence in a dead Quercus petraea tree. Esther Jansma provided a 434 record in the Netherlands (dead tree). In France, we only have a mere 356 years sequence from a living oak in the Compiègne forest! These are only counted (and most often cross-dated) sequences. But, of course, older oaks could exist. Ignacio García González from Spain has an uncertain starting date of AD 1254 for a living Quercus robur in Leon, cored in spring 2005. That is potentially 756 years old. But he still has to check. Estimates based on extrapolation from circumference, with or without using partial ring sequences, can go much further back in time. The excellent synthesis of Jones on oaks (1959, J. Ecol.) is often cited because Jones quoted old papers from 1905 and 1886 where oaks of 930 and 866 years, respectively, where described. I went back to these papers written in old German (thank you to Annegret Kohler for her help in translation). The first one was an estimate calculated from a short ring sequence count. There was no information about the method used for the second one. Thus, in my opinion, these ages can no longer be retained. In 1996, Ratburg Blank at Invenacker Tiergarten, in Germany, counted 193 external rings in a Quercus robur and inferred an age of 826 years from the circumference. Interestingly, Patrick Gassman in Switzerland cored another large oak a few kilometres from the one quoted above. The first one had 453 rings in 56 cm of radius, i.e. a radial growth of 1.2 mm/yr on the average. The second one displayed an incredible radial growth of 3.9 mm/yr for 204 years, three times faster! It means that, as suspected, diameter is a very (very…) poor indicator of oak age. In case one has already observed even faster rates of growth for oaks over 200-yr old, I am really interested. Such fast growing and old trees will help us put a maximum constraint on the age of oaks estimated from diameter. My opinion after this search is that we have no firm evidences for oaks living more than 600 years. And that probably all currently living oaks are below this threshold, and most probably even younger, below 500. I think this applies to the numerous “millennium” oaks found almost everywhere in Europe. Finally, if you count an oak and find it over one of the previous records, or if you know one already counted, it would be worth mentioning it on the forum, at least, or send me a mail. Once again, thank you to all contributors. Best regards, Jean-Luc Dupouey INRA-Nancy University Forest Ecology and Ecophysiology Unit 54280 Champenoux France tel.: 33 3 83 39 40 41 fax: 33 3 83 39 40 22 mail: [email protected] -- Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected]
