Friday, May 22, 2015

15-May-2015 Jumpoff Ridge, Washington

Site locations (click to enlarge)
A USDA entomologist recently gave the Burke Museum a set of spiders he collected in fruit orchards near Wenatchee.  This meant that Rod had several gridspaces in the area that had a dozen or so species known to them, which for Rod's purposes constitutes only a partial sample.  Our goal for the day was to sample additional habitats in one or two of those gridspaces until we increased the species total of each to 21 or above.

Steep-sided Dry Gulch to Rod's left,
Columbia River in background
Purple sage (Salvia dorrii) and
round-headed desert buckwheat
(Eriogonum sphaerocephalus) produced
crab and jumping spiders
Our first stop was Dry Gulch.  Not a likely place to find pine cones for me to tap, but that was ok since we figured we'd be able to collect the minimum number of species (7) in no time, then move on to a higher-elevation gridspace that had ponderosa pines (Pinus ponderosa).  Ha!  So much for plans!  The spiders we found in the habitats near the road were not a diverse enough bunch to complete our sample: just a few species of jumping spider, a crab spider that probably had already been collected in the orchards, and a small number of under-rock species (which all later turned out to be juveniles).

How did that
car get down there?
Wolf spiders (Lycosidae) were
common on riverside cobbles
We decided that the best likelihood of completing a sample was to hike to the gulch's outlet at the Columbia river.  There we hoped to find some productive riparian habitats.  Dry Gulch's bed contained plunges and cliffs, preventing us from taking what would have otherwise been the simple route to the river.  The overland route was straightforward enough, but forced us to wade through a dense sea of cheatgrass (Bromus tectorum), an invasive species whose sharp-pointed seeds are so good at worming their way through boots and socks and irritating the skin within.  We had quite a sock-picking party later, after returning to the car.

This white mulberry (Morus alba)
was loaded with spiders
Rod happy after the
riparian finds
At the river margin I had some success capturing wolf spiders from the riverside cobbles as well as other types from the foliage of the introduced tree species, white mulberry (Morus alba).  For his part, Rod was pleased with the fauna he found under shaded rocks and in riparian herbs.  He would later confirm that we did indeed complete the sample. The trouble was, we had spent most our day doing it.  We still had time to tap ponderosa cones up on Stemilt Hill's Jumpoff Ridge, but only provided we quickly found some.

Beautiful but unproductive ponderosas
on Stemilt Hill
The sorry (unopened) state of
ponderosa cones on Stemilt Hill
Well, we found the ponderosas quickly enough, but as happens sometimes, this stand was a poor cone producer.  I could find few fallen cones, and of those, most were unopened.  In the end, I only managed to find and tap 15 open cones, which produced a total of one juvenile Steatoda (Theridiidae).  Due to the late hour and the 3-hour drive home still ahead of us, there simply wasn't enough time to scout out another stand.  We called it a day and made a quick stop at EZ's Burger Deluxe in Wenatchee before aiming the car towards Blewett Pass and home.

Be sure to read Rod's take on the day here.

Fueling up for the drive home

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