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Index of Subjects ---2114655128-530034482-1326717053=:47778 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable An interesting account Dave.=0AI got some growing from stock from a test tu= be operation - they hold on but not much more.=0ATheir tolerance for cold s= eem variable. Along the Shelburne River=0Athere is a large stand - covers s= everal hectares I would surmise. Very lovely.=0AThe interesting thing is ma= ny plants are growing on top of granite boulders with the=0Aonly soil from = decaying hardwood leaves - the temp of the soil must drop quite low=0Athere= in the winter - so their roots must be hardy.=0AOn the other hand they hav= e a good supply of water during the growing season but no standing or very = little=0Aat least in the winter to make ice. Oxygen does not look to be a p= roblem.=0AUnfortunately or perhaps =A0fortunately it is not an easy spot to= visit but well worth the trip=0Afor me at least. Half the fun is getting t= here - lol=0AHope we can get the snowshoes out soon=0APaul=0A=0A=0A=0A=0A__= ______________________________=0A From: David & Alison Webster <dwebster@gl= inx.com>=0ATo: NatureNS@chebucto.ns.ca =0ASent: Sunday, January 15, 2012 10= :31:30 PM=0ASubject: [NatureNS] The rise and fall of Common Lady's Slippers= (long)=0A =0ADear All,=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 Jan 15, 2012= =0ASUMMARY:=0A=A0 A stand of Cypripedium acaule (Common Lady's Slipper) th= at became established (probably early to mid 1990s) along a section of pick= and shovel woods road that I built about 1984 gradually increased in abund= ance until at least 2006. Sometime after this, drawing on memory between Ju= ne 2009=A0 and summer 2010, abundance decreased abruptly throughout a mappe= d area of 113 m^2. This abrupt decrease may have been triggered by an unusu= al buildup of ice at the soil/snow interface caused by unusually cold soil = and observed about 500 paces NW of this area, or the associated unusually d= eep or prolonged penetration of frost.=0A=0ABACKGROUND:=0A=A0 In the years= 2003 to 2006 inclusive I made rough maps of plant location in a small area= of the North Alton woodlot and recorded state (flowering, fruiting, not fl= owering, browsed, damaged etc.) The total number of plants within the mappe= d area increased each year; 90, 103, 114 and 120 for the years 2003 to 2006= respectively.=0A=0A=A0 In theory one could follow the state of individual= plants over years and initially this worked fairly well. But as plants in = some groups became increasingly crowded the identity of some plants over ye= ars became uncertain. So I discontinued both mapping and counting in 2006.= =0A=0A=A0 Softwoods in this area had been cut about 1950, the woods were s= till fairly open until about 2000 but had started to close in south and wes= t of one portion of the mapped area=A0 by 2006 so I did some thinning in la= te winter ( probably March of 2007 & 2008).=0A=0A=A0 When I hand-pollinate= d some flowers in 2007, 2008 and 2009,=A0 in the previously mapped area, I = noticed no change in stand density but by summer 2010 there were very few p= lants in this area.=0A=0A=A0 The mapped area is not large, about 113 m^2, = but is spread=A0 along aboout 100 paces of road as four relatively distinct= patches. Because all patches were affected it seems unlikely that either d= isease or tree thinning was the cause.=0A=0A=A0 When cutting wood to the N= W of this Lady's Slipper stand, in late winter of 2009, when there were sti= ll scattered patches of snow, I noticed a very unusual condition.=A0 Temper= ature at the soil/snow interface is usually close to 0o C with soil heat gr= adually melting snow at this interface but ice was nearly always present at= this interface and up to about 10 cm thick. Ice at that interface would su= ggest melting from above and subsequent freezing of percolated water when i= t reached cold soil. It seems possible that stand loss was caused either by= cold injury or by direct or indirect effects of low soil oxygen.=0A=0A=A0 = This is of course conjectural but it is something to watch for.=0A=0AYours= truly, Dave Webster, Kentville ---2114655128-530034482-1326717053=:47778 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable <html><body><div style=3D"color:#000; background-color:#fff; font-family:ti= mes new roman, new york, times, serif;font-size:12pt"><div><span>An interes= ting account Dave.</span></div><div><span>I got some growing from stock fro= m a test tube operation - they hold on but not much more.</span></div><div>= <span>Their tolerance for cold seem variable. Along the Shelburne River</sp= an></div><div><span>there is a large stand - covers several hectares I woul= d surmise. Very lovely.</span></div><div><span>The interesting thing is man= y plants are growing on top of granite boulders with the</span></div><div><= span>only soil from decaying hardwood leaves - the temp of the soil must dr= op quite low</span></div><div><span>there in the winter - so their roots mu= st be hardy.</span></div><div><span>On the other hand they have a good supp= ly of water during the growing season but no standing or very little</span>= </div><div><span>at least in the winter to make ice. Oxygen does not look to be a problem.</span></div><div><span>Unfortunately or perhaps &nbs= p;fortunately it is not an easy spot to visit but well worth the trip</span= ></div><div><span>for me at least. Half the fun is getting there - lol</spa= n></div><div><span>Hope we can get the snowshoes out soon</span></div><div>= <span>Paul</span></div><div><span><br></span></div><div><span><br></span></= div><div><br></div> <div style=3D"font-size: 12pt; font-family: 'times new= roman', 'new york', times, serif; "> <div style=3D"font-size: 12pt; font-f= amily: 'times new roman', 'new york', times, serif; "> <div dir=3D"ltr"> <f= ont size=3D"2" face=3D"Arial"> <hr size=3D"1"> <b><span style=3D"font-weig= ht:bold;">From:</span></b> David & Alison Webster <dwebster@glinx.co= m><br> <b><span style=3D"font-weight: bold;">To:</span></b> NatureNS@che= bucto.ns.ca <br> <b><span style=3D"font-weight: bold;">Sent:</span></b> Sun= day, January 15, 2012 10:31:30 PM<br> <b><span style=3D"font-weight: bold;">Subject:</span></b> [Nat