Spider mite populations were monitored following plant bug applications; mainly desert spider mites in 1984 and two-spotted spider mites in 1986. Damaging Ievels did not occurring 1984 but damaging populations did occur in 1986. Pyrethroid insecticides most frequently caused spider mite increases ; organo-phosphate insecticides less so. Some synthetic pyrethroid insecticides gave short-term control of spider mites.