Probably the most common species of thrips occurring on forage crops are:

Frankliniella tritici (Fitch), F. occidetalis (Pergande), F. exigua (Hood) and Thrips tabaci (Lindeman) .

Thrips range from 1/25 to 1/10 inch in length and vary from yellowish to dark brown to black. They have slender bodies pointed at each end and most are winged or wingless, but others may possess nonfunctional wings. The insects puncture the leaves, tender stems, flowers and fruit from which they suck sap and cause the formation of white splotches on the leaves. Fruit frequently fails to set or the young fruit falls off immediately following formation. Severely attacked plants often become distorted, withered and discolored.