Mistblower applications of acephate, chlordimeform, leptopbos, phosalone, and Sevimol® (carbaryl) were evaluated against the gypsy moth, Porthetria dispar (L.), and the elm spanworm, Ennomos subsignarius (Hübner). All materials gave excellent foliage protection, but chlordimeform was not very toxic to either species. Chlordimeform acted as a repellent and was especially effective against the elm spanworm in the field. In laboratory choice tests, gypsy moth and elm span worm larvae were repelled equally by foliage treated with chlordimeform.