The western leaf-footed bug, Leptoglossus zonatus (Dallas) was first noticed attacking Satsuma oranges in Plaquemines Parish, Louisiana in autumn 1997 and since then has become a serious pest. This species typically begins feeding on Satsuma in mid-August and continues feeding through harvest. It causes concealed damage to Satsuma through transmission of the yeast, Nematospora coryli Peglion. Studies were conducted to find an optimum diet for rearing this insect in the laboratory. Results indicated that the combination of fresh raw peanuts, potatoes and Satsumas was the most suitable diet. When given a choice of green beans, potatoes, sweet potatoes, fresh raw peanuts, Satsumas, and carrots first instar nymphs preferred to feed on Satsumas. Second through fifth instars and adults fed frequently on fresh raw peanuts, Satsumas and potatoes. Field observations in October 2003 revealed that adults moved around the tree during the day in order to remain in full sunlight. Fifty six percent of adults under observation in the field did not move during the night from their afternoon location. In the laboratory, both sexes fed more during scotophase than photophase. Females fed longer than males but males moved between fruits more often during a 24 hr study period.