ABSTRACT
Rangeland plants are eaten episodically by vertebrates and nearly continuously by a complex of invertebrates. A few of these species occasionally reach epiphytotic levels but the biological mechanisms which trigger these outbreaks remain elusive. This chapter focuses on the nematode component of the belowground system. It discusses the functional roles of nematodes and reviews some studies which provide insights into the effects nematodes and their compatriots have on the quantity and quality of primary production. The chapter examines the feasibility of actually "managing" this belowground component of grasslands for the specific purpose of increasing long-term primary productivity. It explores the potential of nematodes as part of integrated pest management (IPM) programs for control of other rangeland pests. Any IPM program which incorporates control of root grazers must take into account the long-term effect of the program on rates of decomposition and mineralization.
