Rob: I have seen a situation in freshly cut tree stumps where there was enough change in the growth rings to indicate the rate that the tree was putting on wood. In some rare cases you can actually see in the cell growth that the trees had been slowing up and then after a heavy saturating rain restarted their growth. Much of this can only be observed if a person is both aware of the recent local weather patterns and able to observe a tree stump when it is as freshly cut as possible. A few years ago I did some extensive measurements on tree growth and was able to determine that for a warm moist climate like central WV most of the actual volume growth seems to take place in less that 30 days of the 140+ frost free days we normally have. In the deep woods, the creek levels rise and fall so quickly relative to days of sun opposed to days of rain you can almost hear the trees sucking the water out of the ground....totally saturated ground in mid June appears to dry out to the point where the leaves in the tips of the crowns of hardwoods will wilt during the height of sunlights' intensity in the mid afternoon in less than five days. The longer the trees stress out as they are trying to suck water out of the ground the quicker that annual growth stops. We had several inches of rain last week and early this week in this part of the world....enough so that there was localized flooding and a saturated water table....with water standing on fields, in gardens and winter "springs" freely flowing. After just three days without rain all small streams have already dried up but the yellow poplars are setting out new leaves....in a hot week without rain they will lose their vigor and growth will noticeable slow. Three weeks of very dry weather will pretty much shut down diameter growth for the year.. Russ In a message dated 8/6/2009 8:51:47 A.M. Eastern Daylight Time, [email protected] writes:
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] -~----------~----~----~----~------~----~------~--~---
