Collego™ is a selective postemergent mycoherbicide for the control of northern jointvetch [Aeschynomene virginica (L.) B.S.P. # 2 AESVI] in rice (Oryza sativa L.) and soybean [Glycine max (L.) Merr.]. Collego is a two-component product. Component A is a water-soluble spore rehydrating agent while Component B is a water-suspendible dried spore preparation of the fungus Colletotrichum gloesporioides (Penz) Sacc. f. sp. aeschynomene ATCC 20358. Both components are packaged in an 18.9-L plastic mixing container. A mixture containing 0.95 L of Component A and one package of Component B will treat 4 ha. The dried spore component is packaged by number of viable spores rather than by weight. Consequently, the weight of each package will vary from lot to lot, but each package contains a minimum of 75.7 × 1010 viable spores.