Establishing Action Thresholds for Control of Cankerworms in Regina, Saskatchewan, Canada    (View PDF)

Russell Eirich

Abstract: An action threshold (AT) is often established to determine if and when control treatments are required for pest populations. In municipal settings, control treatments for insects defoliating the urban forest are typically determined in response to customer requests, maintenance demands of highly visible municipal public spaces, economic requirements, and actual insect damage. In 2006, the City of Regina Integrated Pest Management section created a new method of establishing an AT for cankerworm control by determining if monitoring counts for female cankerworms (Paleacrita vernata Peck and Alsophila pometria L.) were greater than 95% of an identified “normal” population range when based on historical records.

Keywords: Acer; action threshold; Alsophila pometria; defoliation; empiric rule; Fraxinus spp.; Geometridae; Lepidoptera; Paleacrita vernata; Populus spp.; Ulmus americana

https://doi.org/10.48044/jauf.2008.009