next message in archive
no next message in thread
previous message in archive
previous message in thread
Index of Subjects
Date
On 9/3/2010 11:39 AM, David & Alison Webster wrote:
> Are the distances (e.g. 4.8 km ESE Kentville) as the crow flies or along
> the shortest highway route ? From the Post Office or some other zero point ?
* they're straightline distances: use the lat/long co-ords if you're
going out to find the stands. I use either the central intersection or
bridge of a settlement as a reference point, or else (e.g. for
Kentville, which we just zoomed past) the place designated by google as
the centre of the settlement.
> Does the absence of Phragmites stands along secondary roads mean that
> only main roads were surveyed or does it reflect a distribution that is
> limited to main roads ?
* we haven't driven enough minor roads to say.
> Is it possible that intensive use of highway salt gives saline tolerant
> Phragmites an advantage ? Shoulders on main highways may have white
> patches into late summer.
* that possibility is often spoken of, though I don't know if it has
been studied. The problem is that establishment mostly occurs either by
germination of seeds, or transport of rhizomes, during road
construction, and salt may not affect those processes much.
Environmental differences might be expected to mostly affect the rate of
spread, but it might be hard to get authorities to stop salting a
stretch of road in the interests of studying the rate of spread of
Phragmites.
* we're preparing to monitor calling by Psudacris crucifer through the
course of the storm.
fred (parked inland, in a partially regenerated clearcut near the
Halifax airport, and preparing to monitor calling by Psudacris crucifer
through the course of the storm).
------------------------------------------------------------
Frederick W. Schueler & Aleta Karstad
Bishops Mills Natural History Centre - http://pinicola.ca/bmnhc.htm
now in the field on the Thirty Years Later Expedition -
http://fragileinheritance.org/projects/thirty/thirtyintro.htm
Daily Paintings - http://karstaddailypaintings.blogspot.com/
RR#2 Bishops Mills, Ontario, Canada K0G 1T0
on the Smiths Falls Limestone Plain 44* 52'N 75* 42'W
(613)258-3107 <bckcdb at istar.ca> http://pinicola.ca/
------------------------------------------------------------
------------------------------------------------------------
next message in archive
no next message in thread
previous message in archive
previous message in thread
Index of Subjects