Lee, Interesting topic. Have you seen any tree species ecotypes that seem to follow a natural boundary like terminal moraine, shift in soil taxon, etc?
Gary On Nov 3, 2009, at 3:24 PM, Bob <[email protected]> wrote: > > Lee > > Thanks for weighing in on this topic. In the future, I'll be > cautious about accepting that explanation when I hear glaciation given > as defining the range for a species. I'm embarrassed to admit that > I've often repeated the glaciation explanation for cucumber magnolia's > absence from part of New York. > > Bob > > Sent from my iPhone > > On Nov 3, 2009, at 3:06 PM, Lee Frelich <[email protected]> wrote: > >> >> Bob: >> >> I am always amazed that people attribute ranges of various trees or >> other organisms to glaciation. It seems unlikely that a glacier that >> existed 14,000 years ago can control the range limit of species >> today, >> especially for trees that can grow in a wide variety of soil types. I >> have been told the same about native earthworms--that they only >> occur in >> unglaciated areas, but in WI they occur only in the glaciated part >> and >> not in the unglaciated part of the state. There is always a >> possibility >> that a species could grow on either side of the glacial boundary by >> chance. There are also areas where the glacier scraped the soil away >> down to bare rock, which does have an influence on what grows there, >> but >> this effect does not occur at the scale of tree species ranges. >> >> Lee >> >> [email protected] wrote: >>> Kirk, >>> >>> Yes, I see the distribution goes fairly far north. Those >>> distribution >>> maps existed at the time I was told about the limited range factor. >>> I'm now puzzled. The ecologist who told me about the glacial >>> boundary >>> is well respected. I wonder what he knew that we don't. >>> >>> Bob >>> >>> ----- Original Message ----- >>> From: "Kirk Johnson" <[email protected]> >>> To: [email protected] >>> Sent: Wednesday, November 4, 2009 12:16:59 AM GMT -05:00 US/Canada >>> Eastern >>> Subject: [ENTS] Re: King Pennisula, Allegheny River, Forest County, >>> PA >>> >>> Bob, >>> >>> I don't remember hearing that before, so I don't know if it's true. >>> However, the attached distribution map I found online seems to >>> indicate otherwise (showing range into NYS all the way to Lake >>> Ontario). >>> >>> On the other hand, the Allegheny NF & environs does seem to be a >>> good >>> home for cucumber magnolia anecdotally speaking. There are a lot of >>> them here and some of them are large, so they seem to like it here. >>> (They are one of my favorites.) >>> >>> Kirk >>> >>> >>> >>> >>> >>> >>> Kirk, >>> >>> I was once told by a forest ecologist from Vermont that the >>> cucumber magnolia appears south of the glaciated zone in western >>> NY-PA, but not in it. I presume there isn't a sharp line of >>> demarcation, but practically so. Is this explanation for the >>> distribution of cucumber magnolia still in vogue? >>> >>> Bob >>> >>> ----- Original Message ----- >>> From: "Kirk Johnson" <[email protected]> >>> To: [email protected] >>> Sent: Tuesday, November 3, 2009 11:32:59 AM GMT -05:00 US/Canada >>> Eastern >>> Subject: [ENTS] Re: King Pennisula, Allegheny River, Forest >>> County, PA >>> >>> Bob, >>> >>> That is true. To the west of the Allegheny River and to the east >>> of the Big Level was glaciated. But what is today Allegany State >>> Park in NY and the Allegheny NF was not glaciated. >>> >>> Kirk Johnson >>> >>> >>> >>> >>> Ed, >>> >>> I am jealous. The Connecticut River corridor has some fine >>> trees, but the Allegheny River has sycamores and silver >>> maples that exceed any I've found along the Connecticut. >>> If I remember correctly, the area of the Allegheny in PA >>> wasn't glaciated. Is that correct? >>> >>> Bob >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>>> >> >>> > > > --~--~---------~--~----~------------~-------~--~----~ 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] -~----------~----~----~----~------~----~------~--~---
