(also choke), a disease of grasses caused by the cattail fungus Epichloe typhina. Among the many plants affected by the disease are timothy, orchard grass, fescue, bromegrass, and couch grass. A thick feltlike body forms on the upper section of the plant stem prior to blooming; the growth is first white, then yellow, and finally brownish yellow. Plant development ceases, and spikelets do not form. The fungus spreads by means of conidia. The disease can be combatted by early cutting of the grasses for hay.