California produces approximately 30 percent of the total U.S. production of fresh market tomatoes and approximately 85 percent of the processing tomatoes. Of the California total, the southern desert valleys produce about 10 percent of the fresh market and 5 percent of the processing tomatoes. The tomato fruitworm, tobacco budworm, and beet armyworm are major pests of both fresh market and processing tomatoes in the southern desert valleys, attacking the fruit and sometimes causing serious economic loss. The tomato fruitworm and beet armyworm also are major pests of tomatoes in other areas of California.

The author gratefully acknowledges the assistance of C. Carter, H. Hakakihara, J. Hayashi, and R. Hasegawa for their help in the collection of field data.