Privet leaf miner damage

Following the winter’s damage, I’ve been keeping an eye out to make sure the privet bushes recover OK. By and large, they are doing just that. However, I’d say some are a little weaker than would be usual, but it’s hard to tell. One thing I have noticed though is a surge in the amount of leaf miner damage.

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Damage on a privet leaf caused by leaf mining caterpillars (Gracillaria syringella)

The damage first shows as brownish marks on the leaves. They quickly expand to become a large brown blister. By this stage the blisters are easy to pull open and inside there are little tribes of larvae living a sheltered life between the upper and lower leaf surfaces.

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Inside the blister there are little tiny caterpillars – they’re quite hard to see and to photograph because as soon as their blister is burst they try and wriggle away to hide

These larvae will grow up to become tiny little micro moths – Gracillaria syringella. As the name suggests, they also mine lilac (Syringa) leaves and are known as lilac leaf miners as well as privet leaf miners. There are plenty of them on the lilac bushes this year too.

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Leaf miner damage on a lilac leaf
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…and here are the larvae inside the lilac leaf’s blister