Thursday, July 26, 2007

our structure

In the time of ripening elderberries the days are characterized by stands and fluff. The fluff is, predominantly, the feathery pappi of Compositae, but also willow and willowherb. The stands are the tall herbaceous plants that muster on roadsides, waste and neglected fields. It's high summer, though this year we're still under daily rain.

A few characteristic herbaceous species that form or contribute to these stands where I live: stinging nettle, rosebay and great willowherbs, hemlock, hogweed, wild carrot, corky-fruited water-dropwort, water figwort, teasel, common ragwort, mugwort, prickly and great lettuces, spear thistle (plus creeping thistle, welted thistle, marsh thistle...), burdock, bristly oxtongue, perennial sow-thistle.

The stand is like an annual and herbaceous approximation to the climax vegetation of trees. A massed stand of nettles looks a bit like a small version of Siberian conifer forest - the same astounding symmetries. Expose the centre of the stand and the resemblance is even closer: the stout stems of the nettles are packed close together and, in their lower portion, brown and leafless - no light penetrates into this gloom. Only the top half of each plant is busy with the activity of leaf and flower, a hot shop. Same thing with a stand of great willowherb - the dead leaves on the lower stem are now chestnut brown and hang withered and adpressed to the stem.

The stands aren't beautiful like the plants we notice in spring and early summer; they are active, productive and complicated spaces. They aren't immaculate tendrils of colour on a blank canvas; they bear their record of diseases for all to see. They are fixed processes. A great town of insects lives and eats and multiplies in their vicinity, they are crowned with birds and haunted by small mammals. Human beings may mow or scythe a stand, but otherwise they never penetrate into one - a world that is entirely alien to us and safe from our intrusion lives just beside our own routes.

In bad weather the composite flowerhead is usually held patiently closed. When the sun dries it, it opens, and then away goes the fluff. As a method of seed dispersal it's so obviously effective that it's almost a bit boring. The horizontal dispersal needs dry air. When it rains the pappi get waterlogged, bedraggled, they no longer float but drop and stick to things. This is by design, to achieve the vertical part of the dispersal, i.e. to get the seed (achene) back down on the ground, and at a time that is optimal for being swilled into a crack in the rich, moist soil.

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