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Sunday, July 20, 2008

Harvestmen Harvested

See the Picasaweb album for more pictures from this hike.

I love this time of year. Orange daylilies, blue chicory, and hot pink sweet peas shout from the roadside like some exuberant shapenote choir transposed from sound to color, and occasionally a patch of black-eyed susans bursts into a bravura solo. The only combination I like better happens in late summer when the fields fill with yellow and purple as the New England asters and the goldenrod blossom side by side.

I parked at the Freber (aka Hodge) Road trailhead and spent a few minutes enjoying the profusion of wildflowers. The mullein blossoms weren't what you'd call showy, but the way the spikes towered over the other plants made them seem like the natural leaders of the yellow contingent. Of course St John's wort, with its blasts of saturated yellow, kept drawing my eye back down near the ground. Looking upward again, I finally picked out the lemon-yellow stigmas of a few evening primrose that, as usual, I'd mistaken for mullein at first glance.

The teasels kept drawing my eye, and again I thought how particularly evocative they are. In the winter, when the rest of the dead flowers are laid low under a blanket of snow, the teasels stand there, alone and just as dead, with only a light dusting of snow to show for their stolidness. They have an aching sadness: all the life - all that was green and white and wet - has fallen away from their stems and pods, and what's left seems to embody the funereal dryness that Poe called "crisped and sere". On this summer day, though, they told a different story, catching my eye with their contrasting textures and colors. Each flash of delicate lavender was a band of tiny flowers around the middle of a pincushion-like head, which sat inside a phalanx of thorny bracts. After reading the Wikipedia article I know that that lavender band was poised to split; as a matter of fact, if you click on the picture above you'll see what Grace just noticed: on one of the teasels in the background the ring of blossoms had already split in two.

The Queen Anne's lace were in full flush, forming a sparse web over the lower greenery like a pearled snood. The good old Tyrol knapweed formed a vibrant purplish backdrop within the shadows of the lower greenery, while burnt umber froths of curled dock made the roadside look like it had been singed by a selective fire. Just before I headed onto the trail I noticed a yellow cinquefoil that I don't think I'd seen before. I've since identified it as rough cinquefoil.

One of the first interesting things I saw was a harvestman with only five legs. I've seen plenty with one or two legs missing, but this is the first one I've noticed who'd lost three - and it had lost them all from one side! It seemed to be getting around perfectly well anyway.

Moving on, I saw a harvestman of a species I didn't think I'd seen before - it's always hard to say because the details are too small to see with the naked eye. That's one of the reasons I love macro photography - the closeup shot of this guy revealed a beautiful Rorschach pattern dappling its body.

Within a few hundred yards I'd reached the blackberry patches that cover both sides of the trail. Two weeks earlier, back in Millburn, I'd noticed that the harvestmen seem to love wineberry bushes, so I inspected these blackberry bushes very closely. Not only did I find that each plant was practically covered with harvestmen, but I discovered the unexpected theme of the hike: I was walking through a hidden harvestman graveyard.

I'd seen plenty of spiders lurking within leaves that they'd curled up with their own webs, so when I noticed a downward-curled blackberry leaf on an otherwise thriving plant I turned it over to see what was underneath. The few small black filaments I saw looked surprisingly familiar: I was almost sure they were harvestman legs. At first I thought I might have been mistaken, and anyway the harvestmen might not have been eaten - they could have simply tugged free of those trapped legs and continued on. But I kept seeing similar bundles, so I started to think that some local spider favors harvestmen. Then I saw the flaw in my logic. This summer I've trained my eye to see harvestmen, and now it's clear that they are bloody well everywhere! And since they seem to be constantly crawling along every surface they may represent 99% of the species that ever touch those spider webs. Of course the spiders are eating harvestmen - they're the only game in town! And I did eventually find proof that the spiders were eating them: the biggest clump of remains contained not just legs, but the dried husk of a harvestman's body. See the straw-colored blob in the closeup above?

I saw more and more of those down-curled blackberry leaves - once my eye got the hang of it I couldn't stop seeing them - and although concealed webbing was responsible for all of them, I hardly found spiders under any of them. I began to think that I was seeing an arachnid behavior that was analagous to that of a human trapper: he sets a bunch of traps throughout his territory and then, as time allows, he comes along and checks them. Again I quickly saw a flaw in my logic: there could have been a spider beneath each one of those curled leaves five seconds before I came along, and the spider could have dropped off when it felt the vibrations from my footsteps. I think I was also wrong about a single species doing all the leaf-curling.

Of the few spiders I found under those curled leaves, almost all of them looked the same to me, and there was something pleasing to me about the thought of a single species of spider harvesting from this whole trail. Again, though, the macro shots tell a very different story. See the spider with the small black spots? I thought that was the same species as the one with the red racing stripes! If you look at the Picasaweb album you'll see other spiders - some with greenish colors, some with fawn-colored stripes - that I also thought were the same! It's amazing how our brains, given insufficient detail, will fill in the gaps in a way that's convenient for what we want to believe. I suspect that when I read up on spider behavior I'll find that this leaf-curling (and perhaps trapping?) behavior is as common as dirt.

While I was in minutiae mode I got to see a lot of the trail's tinier residents: as you can see from the size reference of my dirty fingernail, the inchworm would have fit inside the mouth of the wee frog from the previous day's hike; then there was the little pinkish spider that I almost didn't see because its body was just a few millimeters long. On the other hand, I ran across what I think is the tallest mullein I've ever seen; as you can see from the picture, it's about nine feet tall.

1 comment:

Rosemary said...

Maybe what I have in my yard aren't mullein - they have broad, velvety leaves - the leaf on that looks more like a ragweed leaf. The flower spikes are the same though. I'll have to look them up.