A comparison was made of insecticide residue levels in Florida, Arizona and California. Specifically compared were the degradation of parathion (56382) on three crops, the degradation of parathion and ethion (563122) on oranges in different geographic regions of the country, degradation of four insecticides on oranges in Arizona, and the degradation of two formulations of parathion on oranges. Leaf samples were taken by the Gunther leaf punch technique. Analyses were conducted for both the parent compound and the oxon derivative. Parathion degraded rapidly from the leaf surface of oranges in Florida with the level of insecticide at 28 days being practically zero. Paraoxon (311455) levels were also low. Very similar results were obtained in Arizona, with the exception that there were higher levels of paraoxon remaining, nearly three times the maximum amounts recorded in Florida. While it was difficult to make a comparison to California data, as a much less concentrated solution of parathion was applied there, California orange leaves had more paraoxon on the surface than Arizona orange leaves. Parathion decays very rapidly from apple leaves, reaching approximately zero after 14 days with paraoxon levels reaching similar lows. When comparing apple leaves and grape leaves in California, more paraoxon was found on grape leaves.