Deworming is important to maintaining cattle health and performance. The timing and frequency of treatment will vary depending on geographic location, rainfall, stocking rate, age of the animal, and persistent activity of the product used. Producers in the southern United States in areas with higher rainfall and higher stocking rates may need to deworm twice a year (late May or June and again November or December). Only one treatment may be needed in areas with 15-25 inches of rainfall and moderate stocking rates. Routine deworming might not be needed in areas with low rainfall and low stocking rates.