ABSTRACT
Biological control of weeds is a pest management practice that encompasses dynamic interactions among several independent, living systems. These systems consist of a target weed, a biological control agent, and the other nontarget plants (crops) and organisms in the area of application. An array of environmental conditions encountered by these living systems at any one location or in any given year may cause significant variation in the predicted responses (Kennedy and Kremer, 1996; Kremer, 1998). Despite this complexity, our expectations for biological control are to provide sufficient harm to the weed in a consistent manner to reduce the potential economic damage while not harming the other components in the system. Control is primarily measured by weed mortality, by the suppression of weed growth, or by the inhibition of life cycle development.
