Abundance of Lygus spp. (Heteroptera:Miridae) in canola adjacent to forage and seed alfalfa

H. A. Cárcamo, J. Otani, J. Gavloski, M. Dolinski, J. Soroka


Our objectives were to document the abundance of lygus bugs (Miridae) in canola after the cutting of adjacent alfalfa hay fields and to document their seasonal activity in canola plots grown in close proximity to alfalfa seed. Cutting alfalfa did not increase abundance of lygus bugs in nearby canola in sites near Barrhead, Alberta (1998-1999), in the Peace River area of British Columbia (2000) or near Carman, Manitoba (2001). In Saskatoon, from 1993-1995, lygus bug numbers remained at low levels in seed alfalfa and canola and there was no indication that the pest species (L. lineolaris) in canola moved in significant numbers from the adjacent alfalfa seed field. We conclude that alfalfa forage harvesting generally does not result in massive movement of lygus bugs to nearby canola.


Lygus bugs; canola; alfalfa; forage harvest

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