Last updated at 16:19

Scientists think conkers are smaller this year

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Conker season is in full swing, but scientists are worried that the little brown nuts might be a bit smaller than usual this year.

Conkers can be found growing on horse chestnut trees during the autumn here in the UK.

However scientists think they might be a bit smaller this year because of a bug called the leaf-mining moth.

The moths lay their eggs on the horse chestnut leaves.

When they emerge as a caterpillar they eat the green stuff inside the leaves of the tree.

This causes the trees a lot of stress and can make them weaker and more likely to catch diseases.

Leah has been finding out more about how to protect the trees.