Can I do anything about leaf miner?
Tamsin Wells, by email
Stefan says: Leaf mines are tunnels between the upper and lower leaf surfaces. They are caused by insect larvae called miners; some of them are maggots – the larvae of flies – but most are the small caterpillars of moth species.
One of the most common over the past two years has been apple leaf miner, although in my garden it’s the herb lovage that’s invariably affected before anything else. You ask what can be done about them. To which the answer, on trees, is nothing. They may be unsightly but the effect on the tree is minimal. On herbage plants, like my lovage, I simply snip off the affected leaves and destroy them.