The insect responsible (Olethreutes ferriferana) becomes a small moth in its adult form. In spring, the moth lays eggs on the branches. An egg hatches into a small caterpillar that weaves together the edges of an unfurling leaf to make a safe hiding place. Inside, the caterpillar will grow while feeding on the surrounding leaves and the developing flower buds. In summer, the caterpillar drops to the ground, where it turns into a pupa, overwinters and develops into next spring’s adult moth.
