The use of DDT-impregnated materials as a means of controlling tuberworm (Gnorimoschema aperculella) damage to stored potatoes was demonstrated. Complete tubeworm control was obtained on potatoes stored in burlap bags dipped in xylene solns. containing 1-5% DDT. Treated bags still gave complete control ten months after dipping. Confetti and paper streamers treated with 5% DDT gave significant reductions in tuberworm populations but not complete control. In field tests excellent control of the potato tubeworm in foliage was obtained by 2 applications of 1, 2, and 3% DDT-impregnated dusts, 2% regular DDT dust, 5% DDD dust and a 1% [gamma] isomer of benzene hexachloride dust. When applied at approx. 40 pounds per acre, these materials reduced tuberworm populations in all the treated areas over 99% and resulted in a decrease of 97 to 98% in the number of leaflets with tunnels. Single spray applications of a 50% DDT wettable powder, a 50% DDD wettable powder, and a 25% DDT-oil emulsion also gave a high degree of control. A wettable benzene hexachloride powder containing 7.5% [gamma] isomer was significantly less effective than the other materials.