Wednesday, April 29, 2015

17-Jul-2011 Salmon La Sac, Washington

Sample site locations (click to enlarge)
Rod picked the Salmon La Sac area as the destination of our next collecting day.  Although I was enchanted by the curious and mysterious name, I was initially disappointed to find that our sampling sites appeared to be outside of the pondeosa pine (Pinus ponderosa) zone.  But disappointment soon faded with the discovery that western white pine (Pinus monticola) was part of the area's forest mix.  And as it turned out, their cones harbored quite a rich array of spiders.

Site 1. South of Little
Salmon La Sac Creek
Site 1 cone microhabitat
At Site 1, located south of Little Salmon La Sac Creek, I tapped 55 cones and collected 16 spiders and 6 species.  The most common identifiable species was Zanomys aquilonia (Amaurobiidae), but I also collected specimens of several uncommon species including the linyphiids Agroeca ornata and Tachygyna exilis.

Site 2. Rod (L) and my
P. monticola cone source (R)
Site 2 cone
At first the gravel pit that was to be our Site 2 didn't look at all promising from the cone tapping standpoint, but a single western white pine growing at the forest edge saved the day.  I could only find 40 cones to tap, but from those I got 16 spiders and 2 species.  Even the cones I found lying on bare gravel contained spiders, not just those that had fallen on the forest side of the tree.  Euryopis formosa (Theridiidae) was the most common species present.

Trillium in meadow near Scatter Creek
View from the meadow
Next we did some unplanned sampling in a meadow next to Scatter Creek, which was using the road bed for a river bed and prevented us from reaching our intended destination.  No pines there, but it was hard to feel  disappointed about absent cones while wandering around a beautiful mountain meadow in full flower.

Site 3 was behind that
thick wall of green
Callobius canada guarding egg sac
Evening was setting in, but Rod was game for a quick stop at Wish-Poosh Campground (Site 3) on the way home so that I could tap some ponderosa cones.  Like the up-slope sites, the cones at Wish-Poosh were productive.  Tapping 51 ponderosa cones got me 21 spiders and 5 species, including an undescribed dictynid that Rod had also collected from maple leaf litter at Site 1, and a female Callobius canada (Amaurobiidae) guarding her egg sac on the underside of a cone.

Be sure to check out Rod's take on the day here!

Twinflower (Linnaea borealis) growing beneath the lone western white pine on the rim of the Salmon La Sac gravel pit.

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