This phenomena of growth rates in relation to rain is related to many site and species characteristics obviously, but I did note that tree growth habits (which are species specific) were not discussed above; these habits will also have a large influence on growth rates in response to rain. Some species exhibit pre-formed growth (e.g. oaks, true firs, hickories, spruces, ashes), although second flushes can occur if conditions, most notably moisture, allow. This means that the tree grows in accordance with what has been 'pre-formed' in the bud, laid down in the previous year, so there is a connection to last years climatic/site conditions; upon completion of growth, a new bud is set, and, conditions permitting, this bud may break again in the same season, a second flush. A different growth habit, sustained growth, also grows in accordance with what has been 'pre-formed' in the bud but then may continue to grow, without setting a new bud, as long as environmental conditions are favorable; species that exhibit this type of growth are yellow-poplars, hemlocks, sweet gums, and red maples. So obviously species that exhibit sustained growth habits would have an advantage over those that exhibit pre-formed habits, an important consideration in stand dynamics.
Another note that may be helpful when thiniking about tree growth is that photosynthate allocation is prioritized by 1. maintenance respiration; 2. foliage and fine roots; 3. flower and seed production; 4. primary (vertical) growth; and 5. secondary (lateral) growth/ compounds. So to say that you could make a direct correlation, e.g. 2x the moisture yields 2x the width of growth rings, is probably not accurate, but undoubtedly there's a relationship. I would be curious to know if an examination of growth rings, cell size within the growth rings in particular, could determine which years had experienced second flushes; I suspect it would be a very difficult thing to say with good accuracy. Anyone have any insight? On Jul 31, 6:04 pm, DON BERTOLETTE <[email protected]> wrote: > Gary- > I wouldn't think that would necessarily follow...could you further explain? > -Don > > From: [email protected] > To: [email protected] > Subject: [ENTS] Re: rain and growth rates? > Date: Fri, 31 Jul 2009 16:34:43 -0400 > > So, given that lateral growth is more carbon-based than vertical does that > mean that we should expect greater height with all this rain? > > Gary > Prof. Gary A. BeluzoSystems EcologistHolyoke Comm College303 Homestead > AveHolyoke, MA. 01040 > > On Jul 31, 2009, at 2:41 PM, Joseph Zorzin <[email protected]> wrote: > > Now that this is year is one of > the wettest on record, at least in the northeast, just how much can we expect > tree growth rings to reflect this fact? That is- if it rains twice as much as > typical, during the growing season, will that result in a ring twice as wide? > Probably not, but I wonder what sort of relationship there is between these 2 > variables. > > I started thinking about this as I > notice the trees in my backyard showing what appear to be greater growth at > the > top than previous years- especially noticeable on white and pitch pine > leaders. > > Joe > > _________________________________________________________________ > Windows Live™ Hotmail®: Celebrate the moment with your favorite sports pics. > Check it > out.http://www.windowslive.com/Online/Hotmail/Campaign/QuickAdd?ocid=TXT_... --~--~---------~--~----~------------~-------~--~----~ 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] -~----------~----~----~----~------~----~------~--~---
