Fires and Insect Pest Management

Abstract

The impacts of fires on insects, and those of insects on fire regimes, are both complex, and have been studied most intensively in anthropogenic contexts such as forestry and agriculture, in which fire may be employed to suppress pest attack, or the incidence of insect pests increase fire risk or intensity. Indeed, and as in many contexts of gaining knowledge relevant to insect conservation, lessons generated from the economic incentives that drive insect pest management for crop or commodity protection have proved pivotal in increasing fundamental understanding. Relatively comprehensive and well-funded studies on factors influencing the dynamics and impacts of species that influence human wellbeing can illuminate many conservation contexts that are much more difficult to pursue in usually lacking equivalent support. Seasonal movement patterns of pests, often related to use of seasonal refuges or reproduction patterns, can present an opportunity for their suppression – reflecting what some applied entomologists have referred to as ‘weak links’ in the species’ life cycles as phases that can be targeted for control. Spring generation adults of the North American stem borer moth Papaipema nebris (Erebidae) lay eggs on grasses and weeds on field margins, and larvae that initially feed on these progressively move into corn fields as they mature. Pedigo (1999) noted that burning the field margin vegetation in early spring can reduce infestations of near-edge crops by up to 97 %, with yields increasing correspondingly in those areas. An additional benefit is that the margins regrow rapidly, and provide resources and shelter for natural enemies with impacts on crop pests later in the season.