I love the interaction between Don and Ed on the genetic aspects to the Chinkapin Oak. You guys are brilliant! I really find this interesting stuff, it is almost as if certain tree populations being isolated were on islands and able to evolve differently than a general population. In the southern parts of California there is a sub- species of Douglas Fir that evolved larger than normal cones. I believe they are called Big Cone Douglas Fir, I saw several of them on a day hike in Polomar State Forest outside San Diego. Judging from what Ed has stated should I assume that these Douglas Fir became isolated and developed this particular trait or is it a result of the tree species huge range and what we are witnessing is a genetic drift? I believe that Chinkapin Oak does grow as far north as New England and are present in Western Masscahusetts and W. Vermont but in low numbers. Perhaps Bob and can anwser this: Is there a distict differance between these trees here in New England vs what you see in Kentucky?
On Nov 17, 6:44 pm, DON BERTOLETTE <[EMAIL PROTECTED]> wrote: > Ed- > I think we had different visions of the populations that we were speaking of. > > The removal of a single wolf tree from an ecosystem is as you say not likely > to have an effect, genetically. > > In the case of a western coniferous forest in a clearcut operation, the > common industry practice used to be to remove all trees of commercial value > and leave the rest for 'wildlife' trees or 'seed' trees, to meet the > increasing constraints placed on timber sales. Talk about counter-productive! > The removal of 'populations' and the retaining of wolf and seed trees does > affect the genetics of subsequent forests (non-coppice reproducing species). > I have unrealilstically posed 'wolf' trees, 'seed' trees as examples, > although it was once common. > The USFS program collecting cones of genetically superior trees, for seed > collection and reforestation is well-founded and has been viable for at least > a half century that I'm familiar with personally, albeit for a wider array of > genetic traits. > > But to get back to Beth, Neil and Ryan, I think their most interesting point, > was that it was clear from the chinkapin oak population discovered, that age > and dbh predictably didn't have a good correlation. Having spent part of > October visiting ancient foxtail and bristlecone pine forests (2K and 4K max > ages, respectively) in Eastern California, it's clear that oldest of > old-growth trees don't always have predictable relationships with > height/dbh/crown spread superlatives. The ability of these trees to continue > living with a mere fraction of their phloem/cambium periphery intact, is > amazing...as are the misshapen chinkapin oaks in KY's 'Inner Bluegrass > Region'. > -Don > > From: [EMAIL PROTECTED]: [EMAIL PROTECTED]: [ENTS] Re: old trees in the Inner > Bluegrass Region of KentuckyDate: Mon, 17 Nov 2008 17:21:51 -0500 > > Don, > > By genetic selection you can only constrain things that are genetically > controlled. If a certain developmental form is the result of environmental > factors rather than genetic control, a phenotype, rather than a genotype, > then two widely different looking specimens may have the same essential > genetic make-up. Therefore eliminating trees that have a particular form > resulting from environmental factors will not affect the genetic make-up of > the species at all. I don't know and really doubt there is any difference in > the genetics of between a fat old wolfy hemlock and tall columnar hemlocks in > the same general setting. So removing the tall columnar trees will not > affect the frequency of multiple tops or lateral branching expressed in the > trees if they are subject to the conditions favoring multiple tops, nor will > it mean that the trees grown from the multi-top trees will show any more > tendency to form multiple tops than columnar tree if the condition for > producing columnar trees is present. > > In a general population there are really only two main factors that result in > genetic differentiation. So long as the tree can easily cross-pollinate or > interbreed the genetic make-up of the population tends to be pretty uniform. > A large distance say from one end of a species range to the other may result > in genetic drift. The species at one end of the range may express different > physical characteristics than those trees at the far end of the range because > trees at the opposite ends of the range do not freely interbreed because of > the distance. Whether this is because of a genetic difference or not is > another question. Some genes are expressed because of environmental triggers > and may be expressed differently in different areas. Other genetic traits, > similar to blue eyed vs brown eyed traits in humans, may occur in different > frequencies at different ends of the range. Some traits may be missing > completely when comparing one end of the range to the other. But within the > same general area where interbreeding can control in a contiguous population, > the genetic make-up is for practical purposes uniform, even if the trees > express different phenotypes. > > The other places where genetic variations occur are in disjunct populations > and in populations in extreme environments. In these areas less frequently > occurring genetic trait may be concentrated, while others are eliminated > completely. Isolation from the general population allows any favorable > mutation of genetic make-up to spread more quickly that is possible among the > general population with a larger genetic pool. All species tend to show some > genetic change through time, but he change is most rapid in isolated > populations. If you look at the evolution of species over time, what you see > may not be the slow change over time you expect, but a more rapid change. An > isolated population develops a different genetic profile more quickly. Then > if it is merged again with the general population through the natural ebb and > flow of population boundaries with climate change, this change if > advantageous may spread quickly through the general population, may spread > and coexist as a separate entity across the range of the original population, > or even replace the members of the original parent population with the new > variety. > > To focus the point once more, I don't think there is any real genetic > difference among the population of wolf trees and the population of columnar > trees in a given locality, so eliminating one form will not change the > genetic makeup of the population in general. Do I think some trees are > genetically superior to others? Of course, individual trees may have > different genetic compositions and some are "superior" to others. That is > why efforts to save the biggest and best hemlock trees are worthwhile, > because INDIVIDUALS may have superior genetic characteristics. Looking at a > population scale, the populations in an area tends to be pretty uniform in > genetic make-up. The population contains genes representing all the genetic > variability available. > > Ed > > "Two roads diverged in a yellow wood, And sorry I could not travel both. > "Robert Frost (1874–1963). Mountain Interval. 1920. > > > > ----- Original Message ----- > From: DON BERTOLETTE > To: [email protected] > Sent: Monday, November 17, 2008 3:12 PM > Subject: [ENTS] Re: old trees in the Inner Bluegrass Region of Kentucky > > Ed-I of course realize that you were constraining you comments to those > species that rely on coppice reproduction. Leaving fat old 'wolfy' hemlocks, > while taking tall columnar hemlocks, for example, is likely to retain genes > that favor multiple tops, and lateral branching preference. Both phenotypes > are needed for the diversity that favors survival, but the latter is sought > after by the logger/mill interests.-DonRB > > From: [EMAIL PROTECTED]: [EMAIL PROTECTED]: [ENTS] Re: old trees in the Inner > Bluegrass Region of KentuckyDate: Mon, 17 Nov 2008 11:57:05 -0500 > > ENTS > > It is hard to lose genetic diversity in a species short of eliminating the > entire population except for a handful of specimens or by selectively > eliminating a specific genetic characteristic. Timbering is basically a > non-selective process. The trees that sprout up after logging have pretty > much the same genetic characteristics as the original population. They just > don't have the same environment in which to grow. Trees or species that are > adapted to extreme environments are the most vulnerable to genetic loss. > These are populations that tend to concentrate genetic characteristics that > are uncommon in the overall population and tend to preserve any advantageous > mutations that would be lost among the larger genetic pool of the general > population. The characteristics that are concentrated are still present in > the general population and given enough time they could be potentially be > concentrated again in an isolated population trying to adapt to the same > extreme environment. Any true genetic variations limited to the isolated or > extreme environment population would be lost with the effective elimination > of the host population. Again simple cutting is non-selective, so it would > require the population be removed and conditions altered so that the locality > is not repopulated by the sprouts or offspring of the timbered or otherwise > removed species. > > Ed > > "Two roads diverged in a yellow wood, And sorry I could not travel both. > "Robert Frost (1874–1963). Mountain Interval. 1920. > > ----- Original Message ----- > From: Ryan McEwan > To: [email protected] > Sent: Monday, November 17, 2008 9:54 AM > Subject: [ENTS] Re: old trees in the Inner Bluegrass Region of Kentucky > > All: > > I would like to second Neil's main point- these trees may have passed through > a bit of a genetic bottleneck due to human activities...but my gut tells me > that we have only begun to discover the genetic flexibility trees. Plus, > these trees were growing right on rocks, on a palisade, I would not infer > much from their form. I bet you could grow "ideal" trees from one of their > acorns. > > Than, again, if we think their form is a little off from the ideal, I think > maybe that is an indication of our (non-biologically supportable) bias, not > any real evaluation of the inferiority of the tree!!! This whole rat-race we > are all involved in is ultimately about evolutionary fitness, and these trees > have had about 200 extra years of acorn crops, so I reckon they are in much > better shape than their fancy, straight-trunked, cousins who met the saw > long-ago!! > > ryan > > -- Ryan McEwanThe University of Daytonhttp://udbiology.com/content.php?id=1664 > > On Mon, Nov 17, 2008 at 7:27 AM, neil <[EMAIL PROTECTED]> wrote: > Beth, That is great - I love the look of chinquapin oak [or > chinkapin,however you wish to spell it. I'd be careful on estimating tree > agefrom external characteristics. The last tree on the list was largerthan > most trees cored & yet ~ 1/4 of the potential ages. It lives nextto a trail > and an ephemeral stream. I'd guess > > ... > > read more »- Hide quoted text - > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ Eastern Native Tree Society http://www.nativetreesociety.org You are subscribed to the Google Groups "ENTSTrees" group. To post to this group, send email to [email protected] To unsubscribe send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/entstrees?hl=en -~----------~----~----~----~------~----~------~--~---
