I mentioned in a recent post (Gone galling, again, 28 October) that October was a good month to find galls and mines on leaves and, in fact, that also extends into November, or until the deciduous trees have shed their leaves and those fallen leaves have turned to mush, and the leaves of wild plants have also become unrecognisable in the mud under our feet.
So, let’s start this mini series on leaf mines with a look at the blotch mines made on Oak (and sometimes Sweet chestnut) by the larvae of the micro moth Tischeria ekebladella. The blotch starts off looking quite white but often browns, from the centre, with age, giving it a look that one astute observer described as a fried egg. The larva creates a cocoon within the blotch and remains there until its ready to pupate in the springtime. The adult moth emerges from pupation and is on the wing in May and June.
By holding leaves up to the light, I managed to photograph larvae within a couple of mines, though, one of our local moth experts, George, who’s a senior moth ecologist with Butterfly Conservation, told me that the larva in the photo on the right below looks to have been parasitised and a different creature’s larva seems to have emerged from the Tischeria larva. Such is the way of Nature.