Green-veined White

(Pieris napi)


Habitat

This butterfly feeds mainly on wild plants and has a preference for woodland lanes and damp meadows.  It is also found in gardens.

Food

The Green-veined White isn't a garden pest.  The caterpillars mainly feed on garlic mustard (Alliaria petiolata), horse radish, cuckoo-flower, charlock and other wild cruciferae.

Life Cycle

The winter is passed as a pupa.  There are two generations in hot summers, otherwise the second is only partial or non-existent.  The butterflies are out in March and April with second-brood insects on the wing from July into September.  With overlap, it is possible to find Green-veined Whites throughout the summer.

Notes

The heavy veining of the underside distinguishes this species from the plainer Small White.  Males have some spotting on the upperside but the females have heavier markings.  The race found in Britain is Pieris napi ssp. britannica.  There is considerable variation in the colouring and marking of Pieris napi and bred forms in the past have produced striking results, including bright, canary-yellow butterflies, which probably do not exist in the wild any more.  The eggs are laid singly, usually on the undersurface of the leaf.  The larvae are solitary, and well camouflaged on the green leaf.  Pupae are formed attached to a stem by the cremaster with a girdle of silk, hidden in the undergrowth.  The butterflies are migratory, but nothing like to the extent of the other two Whites in this genus.