Their most successful applications appear to be in an integrated approach that employs several management strategies. Livestock grazing may also be considered a form of biological control and commonly supplements weed control in cropping systems. Growers in Australia have sheep graze an area to eliminate some weeds before herbicide application. Goats also have been used in Australia to selectively graze Illyrian thistle. Sheep are used in the fallow land of northern New South Wales and southern Queensland to control any weeds that are missed by an application of glyphosate.
Growers remove the sheep before they trample the wheat stubble.
Effectiveness of livestock would rank goats first, followed by sheep, cattle, and then horses. Straw mulch aids weed control and also suppresses stress diseases such as stalk rot in corn and sorghum. The only insecticide needed during the three-year rotation is a seed treatment for wireworm when planting corn or sorghum. Greenbugs generally require a control measure in sorghum fields that contain no crop residue, but avoid sorghum fields that have good wheat stubble cover, usually saving an application of insecticide. Timely control of weeds after wheat harvest not only saves soil water and reduces weed seed production, but can prevent army cutworm damage to corn and sorghum.