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Archive for March, 2011

goldenrod galls

Photo by Collin Purrington - http://www.flickr.com/photos/cpurrin1/

It’s March in Vermont, and I sit here typing, snow falls outside. After a few balmy days of rapidly shrinking snowbanks and rising creeks, the prediction for today is 3-6″ of new snow. It makes me wonder about the turkey vultures, the robins, the redwing blackbirds, the green tips of daffodils poking up, even about the moth I saw on the wing last night and the hundreds of spiders crowding the winter-flattened grass near the old pond. That was yesterday, when it was spring. Today it is winter again. But not to worry, it is a fleeting renewal, the last-ditch clutch of a season passing. Summer will come. I think the birds, the spiders, and the moth all know this… and so do the Vermonters, although the weather still galls them.

Some months ago, when the temperatures dipped below freezing, but before layers and layers of snow began their assault on the landscape, I went out and found a couple of patches of goldenrod (Solidago species) and collected a few of the many galls on the stems of the plants. Being a curious person, I noted that the galls showed no sign of anything having exited them, and thought that maybe, just maybe, if I kept them inside and warm for a bit, whatever was due to come out in the spring might make an early appearance for me. I assumed that living inside that hardened gall was a small insect larvae that in the spring would emerge as an adult insect. Well, OK, to be honest I remembered cutting a few open as a kid and finding just such a larvae –  a small, grub-like critter. But I had no idea what the adult version was.

Now, patience may be a virtue and all, but we do have this thing called the internet. It wasn’t long before I knew exactly what to expect coming out of the gall… a goldenrod gall fly (Eurosta solidaginis). This classroom-oriented site by Doug Collicutt was excellent, and this site also had some great photos — most of what I share here comes from these two sites. But before we get into the details, let me finish my particular story.

I set the gall in a mason jar with some screening over the top, and left it alone near a heater. I didn’t keep track of how long it took, but it seems like it was two weeks or so before I walked by it one morning and noted something clinging to the screen on top. A little fly with brown, spotted wings.  I hadn’t really thought that the experiment would work, but there in front of me was a goldenrod gall fly. He wasn’t much to look at really – a little, hunched fly that didn’t seem to move around or fly very well. But still, when you consider that as a larvae he was designed to survive a long winter of sub-zero temperatures in a little brown gall, I was still pretty impressed.

click on any of these for some other photos:

I suppose, when you think about it, any life is amazing. It is a beautiful, mysterious world out there, and our own existence is a marvel in itself. But still, there are moments like this that help one to appreciate the complexity and ingenuity of the world.

Think about it. In the spring, just as the sun is pushing the winter’s snow back and tender new shoots of goldenrods are reaching up into the sun, a little brown fly emerges from a dead, brown gall among last year’s stems. It can barely fly, but it wanders around the goldenrod patch on foot, looking for a mate. It has about 2 weeks to live. If it is a male (like the one in my pictures), its entire mission for its adult life is to find a female and mate with her. He doesn’t eat anything as an adult. He mates and dies, and that is it.

If the fly is a female, once she has mated she finds a growing goldenrod, and using her ovipositor, slips an egg through the skin and into the interior of the plant’s stem. I imagine she deposits a few eggs like this. She, too, does not eat. She simply mates, lays the eggs, and dies.

And the magic begins. Egg hatches to larva. The larva begins eating. The plant senses it, and responds by trying to grow new tissue around it and isolate it. Perhaps the larva secretes a chemical that influences the plant’s behavior, but in either case, the plant fails at its attempt to get rid of the parasite. The little larva gets bigger, and the stem of the goldenrod swells around it, forming a gall. Over the summer, the larva eats and eats, stealing from the goldenrod but not killing it. It spends the summer happily in its gall.

There are threats, of course. Anything that kills the parent plant leaves the little larva without its free lunch. There is no emerging early or crawling over to another plant – its whole life depends on the plant it is parasitizing. There are predators, too. Chickadees know what is in the gall if they can get in. Downy woodpeckers definitely have the means to penetrate the gall. One species of beetle (Mordellistena unicolor) is known to burrow into galls to eat the fly larva, and two species of wasps (Eurotyma gigantea and Eurotyma obtusiventris) use ovipositors of their own to deposit an egg inside the gall. When the wasp egg hatches, it eats the fly larva. And of course there is the curious naturalist who sticks galls in mason jars…

In the fall, as the goldenrod becomes senescent, something triggers the larva to dig itself a tunnel out to the edge of the gall, where it stops just at the skin, and retreats back to the middle. As the goldenrod dies, its tissues become hard, and the larva that misses this step would surely be trapped in the middle of an impenetrable wall of gall. And winter comes.

The goldenrod gall fly larva is one of several species of insects that are able to, as the temperatures drop, produce a sort of antifreeze in their bodies that allows them to survive sub-freezing (and sub-zero) temperatures without tissue damage. It is amazing when you think about it. Anything else would succumb to exploded cell walls and massive damage, but not this little larva. Snow falls, perhaps the dead goldenrod topples and the gall is buried in snow. Maybe it stands through the winter, swaying in frigid breezes. Inside the larva waits for spring.

The warmth of spring triggers a change. Metamorphosis. Inside the gall, the larva enters a pupal stage, and then performs the magic of the insect world (think butterflies) when it emerges as a fly. Unfortunately for the fly, it is still stuck inside a gall. But there is the escape passage dug by the larva in the waning days of fall, and only a thin skin of plant tissue between the fly and freedom. Again magic happens. According to Doug Collicutt, the fly “anchors itself and pumps body fluids into a special portion of its head.” What? Apparently the top of its head balloons out because of the fluids, and this swelling pushes out through the last layer of the plant skin. It waits for its head to shrink and its body fluids to go back to their proper spots, and then the fly emerges.

Wow.

Out there past the window, past the falling snowflakes and the sap buckets collecting crowns of snow, there are larvae waiting for their moment. What a cool world.

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The tide has turned in the last week or so. The sun higher, the days longer, the smiles coming.

About ten days ago I noted the first turkey vulture of the spring floating in, and just a few days ago an American kestrel bounced its tail and head as it came to a perch. There are robins around. The cardinals are singing, the chickadees are singing, and the machine-gun drumming of woodpeckers echoes through the hollows. The world is a dripping, warming place.

A fortuitous confluence of events put fishing on my mind. I went on a “man’s weekend” with my brother, which, in addition to the requisite amount of alcohol, meat, and fire, included ice fishing. We chipped holes in the ice with a chisel (earning our fishing and blisters) and set six lines in the ice. And I held fish in my hands… I touched at least 3 brook trout on the weekend. There’s something addictive (addicting?) about touching fish. It is a strange, magical meeting of worlds. It is reaching beneath the surface, into the void, and finding something alive, breathing, and squirming. And beautiful … it is always about beauty, isn’t it? Fish are beautiful, alien creatures.

So I touched some fish. And when I got home, I found a brand-new set of chest waders waiting in the mail. Coincidence?

With brook trout and waders on my mind, I began flipping through a book on fly fishing northern New England and stumbled upon an epiphany. Although the fishing season here in Vermont doesn’t start for another month (unfair!), the season in New Hampshire had been open since January first! The Saxtons River had tossed its ice aside a week ago… those New Hampshire rivers were similarly open. The ponds and lakes were still iced over, and the fish everywhere were just waking, but I had waders… and those brookies this weekend had taken bait…

And so yesterday, as the sun climbed through noon and smiled upon the waking world, I found myself in the Cold River near Alstead — waist deep in spring. The sun glinting off the water, robins flying tree to tree along the banks.

I would like this to be a story about me waiting patiently, working the water carefully, and finally landing a monster of a trout. But this isn’t that story. When you are relatively new to fly fishing, like me, success is measured in more subtle ways. I am no Brad Pitt “shadow casting” into the mighty waters of Montana, after all. I am that guy sitting on the bank trying to untangle yards of line because he cannot fathom the thought of tying yet another knot. I am the guy jumping and reaching to branches in hopes of retrieving a snagged fly. A day where I don’t lose a fly is a highly successful day. And I must say, this day on the Cold River was such a day.

I tried using “streamers” for the first time… In my case just a simple woolly bugger, but still, a different technique of fly fishing. And, of course, because of inevitable circumstances, I was doing it off my left shoulder and casting across quite a current. When the woolly bugger had attracted no notice, I fell back into a familiar pattern of large stone nymph with a copper john dropper. This pattern, with its accompanying split shot and strike indicator, is a whole different world of casting. It is awkward at best, and again was performed off the wrong shoulder and across a current.

And through it all, not one tangle. Not one snagged. Not a single fly sacrificed to the river gods.

And the waders… being new to this game (and cheap), I had favored jeans and sneakers in my previous fly fishing escapades. What a chump! I felt positively comfortable out there… I could walk without stumbling and I felt positively buoyant. The boots gripped the rocks like newfound lovers, my toes suffered the transgressions of not a single rock.

And through it all the spring sun was beaming down, the trees were taking their first breaths, and birds tested the warming air. Not a bad day at all.

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Oil is US

I sat and watched images from Japan this morning for ten minutes or so this morning and was overwhelmed by the images. A wall of what was hard to recognize as water (debris, cars, boats) moving across the landscape… buildings toppling… floating debris on fire. I couldn’t help but feel the magnitude of it — those people killed, uprooted, traumatized. Lives and livelihood taken in one slip of a tectonic plate. And slowly I began to recognize the voices dubbed over the carnage… a woman, the anchor, telling us that there were reports that this should cause the price of oil to drop. Another station with images of a watery apocalypse, and another confident voice talking about how this might ease the prices at the gas pump.

Is this what it has come to? That our gluttony has finally conquered our compassion? That a tragic day for thousands, millions of people, has come to measured in words like economy and barrels? Really? This tragedy in Japan registers for us only in dollars, not tears?

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