Cabbage whites are common butterflies of gardens and other flowery places, where they cause no harm at all. Their dirty-green-coloured caterpillars, on the other hand, can wreak havoc in vegetable gardens and on farms, where they quickly reduce cabbages and other brassica plants to mere stalks. The caterpillars are full of distasteful chemicals, so are not eaten by birds, however, one parasitic wasp species loves them: the wasp lays its eggs inside the caterpillar where they are eaten by the grubs. British populations are bolstered by migrants from the continent.

How to identify common garden butterflies.

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