Mid and Late Season Foliar Sprays and the Evaluation of Thimet for the Control of the Colorado Potato Beetle, 1980

‘Katahdin’ potatoes were planted on May 2 in a Merrimac sandy loam soil at the Valley Laboratory, Windsor. Plots consisted of 3 rows 1.0 m apart and 4.6 m long. Each row had 16 plants. There were 4 replications arranged in a randomized design. Temik or Thimet was applied directly to the seed furrow at planting. Thimet was compared to Temik for early season beetle control. On Jul 7, when Colorado potato beetles began to survive on plots treated with Temik, weekly spraying of foliar insecticides was initiated. Six sprays were tested through Aug 20. The 2 synthetic pyrethroids. Ambush and Pydrin were compared directly. The benefit of adding Thiodan to either Furadan or Ambush was determined. Ambush, the most effective material in previous trials, was also used to control beetles in plots treated with Thimet.