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Wednesday, October 27, 2010

Ghost Leaves


Click image to enlarge.

Here's a curious phenomenon I observed in the Fourmilab driveway today: “ghost leaves” made of dried mud. Here's what happened: due to the excavations for the pipes for the village central wood heating plant, the driveway was covered in a uniform layer of dust. Autumn leaves fell on top of this dust, and then fog and light rain dampened them and cemented them to the top of the dust, which turned into mud.

Next, a serious downpour washed away most of the mud, except for that which was protected by the leaves. (You can see trails where some of the mud ran away to the left, which is downhill in this shot.) Finally, we had a few sunny, dry days, followed by a day of high wind, which allowed the leaves to dry and then blow away in the tempest. This left little islands of dried-out mud in the shape of the leaves which protected them from the rainstorm.

They'll all be gone after the next rain.

Posted at October 27, 2010 20:41