Ed- I suppose it might vary from species to species, region to region, but in general it has to do with disturbance and a trees response. The re-iterations you mention are most typical in conifers, as they typically exhibit 'apical dominance'. Which is to say, the tree wants to grow into the sunlight. When some manner of disturbance causes damage to the apical tip, like a significant ice storm, a wind event that breaks the top out, and/or other such single tree calamaties. The tree's response, somewhat dependent on genetic predisposition, often times is to route the trees energy to the next best branch. I have seen a number of species do this several times (tree lives long enough, emerges high enough above the forest canopy, it gets taken back, sometimes, time after time). I don't think I have a photo anymore, but there are a number of "candelabra trees" in the redwoods of northern California that may be the most extreme example of this, in part due to their longevity (number of opportunities for coastal exposure to Pacific storms), and in part due to their energy allocation strategies. -Don
> From: [email protected] > To: [email protected] > Subject: [ENTS] Re: Another Big White Pine > Date: Wed, 11 Mar 2009 23:03:50 -0400 > > > ENTS, > > I am wondering about these reiterations. We have talked about it before, > but everything is not clear in my mind. A reitteration is what exactly? It > appears to be a secondary trunk formed ntially from an upturned limb... How > do they form and why? What species of trees are know to have these > reiterations? I know this white pine, some of the hemlocks in the Tsuga > Search project, Many of the giant conifers from Bob Van Pelts book. Are > there examples of reiterations in trees that are not conifers? Please > enliughten me on the subject. > > Ed Frank > > > > _________________________________________________________________ Windows Live™ Contacts: Organize your contact list. http://windowslive.com/connect/post/marcusatmicrosoft.spaces.live.com-Blog-cns!503D1D86EBB2B53C!2285.entry?ocid=TXT_TAGLM_WL_UGC_Contacts_032009 --~--~---------~--~----~------------~-------~--~----~ 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] -~----------~----~----~----~------~----~------~--~---
