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 :o HELP!
Nasty little larvae have invaded my sorrel plants - they are between the top an bottom layer of each leaf, eating through the middle.  Initially it just looks like a pale area on the leaf but when you look closely their is a little wiggler actually within the leaf and it has eaten the middle out of the whole pale patch.  Larvae are white and about 3-4mm long.  Anyone any ideas what they are and how to discourage any more? I have removed all the afflicted leaves but there are more and more appearing.

Thanks,

Piglit