I will add to what Amartya said with this: Salix is also very fast growing and can often reproduce both sexually and asexually, making it a good ruderal species. It also has high ET rates. Our limited research in New Mexico wetlands showed that S. exigua was tolerant of crowded (i.e. competitive) conditions and poor soils. Certainly poor soils are not uncommon in high alt and lat.
Anna A. Sher, Ph.D. www.anna.sher.com Associate Professor Department of Biological Sciences (303) 871-3538 [EMAIL PROTECTED] Director of Research, Herbaria & Records Denver Botanic Gardens (720) 865-3589 Date: Sun, 24 Aug 2008 05:19:52 -0700 From: Geoffrey Patton <[EMAIL PROTECTED]> Subject: Re: Salix success? Success of exotics? =A0 Why do so many exotics species become alien pests? We are all aware of the = explanation for that success being the lack of predatory species. Is this a= ll there is to the story? Could their longer evolution in their "homeland" = have given them genetic advantages? Do as many New World species become inv= asive exotics in the Old World?=20 Geoff=A0Patton =A0--- On Sat, 8/23/08, David Inouye <[EMAIL PROTECTED]> wrote: From: David Inouye <[EMAIL PROTECTED]> Subject: [ECOLOG-L] Salix success? To: ECOLOG-L@LISTSERV.UMD.EDU Date: Saturday, August 23, 2008, 11:20 PM What makes Salix (willows) so successful at high latitudes and high=20 altitudes? Unusual physiological traits? =20 =0A=0A=0A ------------------------------ Date: Sun, 24 Aug 2008 12:39:21 -0400 From: Amartya Saha <[EMAIL PROTECTED]> Subject: Re: Salix success? Success of exotics? Salix spp can tolerate soils flooded for several months at a stretch (depending on species). I"m guessing here... high latitudes have large areas that are poorly drained. High altitudes also have their share of lake margins, riparian margins and bogs... Roots adapted to anaerobic environments can be part of the story. Quoting Geoffrey Patton <[EMAIL PROTECTED]>: > Why do so many exotics species become alien pests? We are all aware > of the explanation for that success being the lack of predatory > species. Is this all there is to the story? Could their longer > evolution in their "homeland" have given them genetic advantages? Do > as many New World species become invasive exotics in the Old World? > > Geoff Patton > --- On Sat, 8/23/08, David Inouye <[EMAIL PROTECTED]> wrote: > > From: David Inouye <[EMAIL PROTECTED]> > Subject: [ECOLOG-L] Salix success? > To: ECOLOG-L@LISTSERV.UMD.EDU > Date: Saturday, August 23, 2008, 11:20 PM > > What makes Salix (willows) so successful at high latitudes and high > altitudes? Unusual physiological traits? > > > > > PhD candidate Department of Biology, University of Miami www.bio.miami.edu/asaha ------------------------------ Date: Sun, 24 Aug 2008 09:57:13 -0700 From: Patrick Foley <[EMAIL PROTECTED]> Subject: Re: Salix success? David Inouye wrote: > What makes Salix (willows) so successful at high latitudes and high > altitudes? Unusual physiological traits? > > The genus /Salix/ has several preadaptations for life in harsh cold conditions of considerable past disturbance: 1) As a wetland plant it can handle tundra soils. 2) As a perennial it can handle short growing seasons. And for a perennial it is very flexible, hence its worldwide use for basketry. 3) It shows a lot of environmental plasticity dealing well with flooding and krumholzing. 4) It is an excellent colonizer due to wind and water dispersal (after glaciers and other flooding denudations). 5) Possibly its pollination system allows it to handle low population counts at times, or has helped to speed its diversification and adaptive evolution. The sister genus /Populus/ shows some of these traits, but is wind-pollinated, not very diverse and not very flexible. But note that aspens have an incredible geographic range. Alders Alnus are not closely related but share many of the willow traits, except animal pollination and easy wind dispersal. They make up for it with nitrogen fixation. I'm guessing that you are wondering how insect pollination evolved in /Salix/. So am I. Patrick Foley [EMAIL PROTECTED] ------------------------------ Date: Sun, 24 Aug 2008 17:48:40 +0000 From: Sharif Branham <[EMAIL PROTECTED]> Subject: Re: Salix success? Success of exotics? Some of the most successful non-native invasives are generalist species that can tolerate a wide range of habitat types, modify their environment or remain viable as seed for a very long time. Many of these species also emerge earlier in the growing season and do well in disturbed environments. If you couple these factors with the fact that many non-native invasives provide lots of fruits or seeds for wildlife to feed on you have a potent combination for biological success in the new environment. Many of the seeds from the non natives are not digestible by the animals that feed on them and they benefit from the transportation that the animal may provide. Sharif ------Original Message------ From: Geoffrey Patton Sender: Ecological Society of America: grants, jobs, news To: ECOLOG-L@LISTSERV.UMD.EDU ReplyTo: [EMAIL PROTECTED] Sent: Aug 24, 2008 8:19 AM Subject: Re: [ECOLOG-L] Salix success? Success of exotics? Why do so many exotics species become alien pests? We are all aware of the explanation for that success being the lack of predatory species. Is this all there is to the story? Could their longer evolution in their "homeland" have given them genetic advantages? Do as many New World species become invasive exotics in the Old World? Geoff Patton --- On Sat, 8/23/08, David Inouye <[EMAIL PROTECTED]> wrote: From: David Inouye <[EMAIL PROTECTED]> Subject: [ECOLOG-L] Salix success? To: ECOLOG-L@LISTSERV.UMD.EDU Date: Saturday, August 23, 2008, 11:20 PM What makes Salix (willows) so successful at high latitudes and high altitudes? Unusual physiological traits? 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