"If this trend continues, flea beetle population will reach economic injury levels in many horticultural crops especially in areas with large acreage of canola and cole crops," the province said.

"Flea beetles are small, dark, jumping beetles that over winter as adults under leaf litter along fence lines and shelter belts," says Jamie Motta, entomology technologist, entomology program at Alberta Agriculture, Food and Rural Development's Crop Diversification Centre North (CDCN), Edmonton.

"Most crop damage occurs in the spring when adult beetles emerge and begin feeding on cotyledons and the first true leaves of young plants. Late maturing vegetable crops such as potatoes, tomatoes, peppers and sugar beets can become heavily infested in the fall because the leaves remain green for a longer period. Flea beetle damage is easily recognized. The adults chew small round holes in the leaves giving the plant a shot hole appearance. Extensive feeding during hot and dry conditions may destroy an entire crop during the early stages of development."

Producers can reduce flea beetle injury by increasing seeding rate and controlling cruciferous weeds such as flixweed, stinkweed and wild mustards prior to emergence or transplanting of the crop. Sprinkler irrigation applied during warm dry conditions will drown the adult beetles and improve crop development and vigor making the crop less susceptible to feeding damage.

"For crops such as broccoli, cabbage and cauliflower that require cosmetic protection, there are several chemical insecticides on the market proven effective against flea beetles," adds Motta.