A preliminary report of studies on feeding, development, oviposition and survival of Archips fumiferana, as well as the effect of budworm feeding on trees, conducted in n. New York in 1946 and 1947. Feeding by the budworm on balsam staminate flowers did not increase their egg potential or alter the sex ratio. Feeding on old foliage of red and black spruce 2 or more yrs. old caused the larvae to suffer high mortality and to pass through 7 or 8 instars before pupation. Those which fed on old balsam fir foliage showed high survival. Mortality during the period between hatching of eggs in the autumn and the needle mining period in the spring varied from 75 to 84% in 1947, and 18 to 2.8% of the populations studied reached the adult stage. Increment borings indicated that budworm defoliation affected the rate of growth of balsam only after the trees had suffered 2 yrs. of heavy defoliation of the current growth followed by a 3d year of medium defoliation.