DDT, benzene hexachloride, and chlordan are relatively insoluble and re-peated applications may accumulate in the soil. Four years after being incorporated into soil these materials were still toxic to plants. Chlorinated camphene breaks down under certain conditions. The toxicity to plants varies with different soil types. Some plants are more susceptible than others, and marked differences were found even among vars. within one sp. of plants. Direct plant damage from foliage application appears to be only a minor problem with most crop plants compared with the problems accompanying an accumulation in the soil. All 4 insecticides will depress growth of some seedlings when incorporated into some soils, even in amts. as small as 25 lbs. per acre. Root development may be retarded with some plants. Benzene hexachloride is the only one of the 4 thus far found to affect the flavor of some edible plant parts.