During the course of control investigations on the black-headed budworm, Acleris variana (Fern.), a preliminary difficulty occurred in the mass rearing of budworm larvae under laboratory conditions. In the forest the eggs are laid on the needles of hemlock and balsam fir trees in late summer. The young larvae emerge the following spring and migrate to the growing buds where they commence active feeding. Under laboratory conditions, however, cut hemlock twigs shed their needles in a very few days and thus the budworm eggs are shed with the needles and exposed to desiccation.