They are the insects that work for you: pollinating your crops, controlling insect pests, eating weeds and weed seed, decomposing stubble and plant residues, freeing up nutrients for the next crop, or improving the soil. Alberta Agriculture and Forestry (AF) presents a webinar about these beneficial insects on Tuesday, March 20, 2018, at 10 a.m.
“If it wasn’t for these beneficial insects,” says Harry Brook, crop specialist at the Ag-Info Centre. “We would have poorer crops to harvest in the fall. There are legions of them out there and they are the unsung heroes that keep destructive insects and other pests under control.”
These beneficial insects work for field crops in several ways. “The insects may merely hunt and eat the adult pests. They may also lay eggs in problem insects. When those eggs hatch, the larvae eat their way out of their host, preventing ongoing propagation of more problem insects,” mentions Brook.
There are 10 large groups of insects that help control pest species. ”The most important of these are the true bugs, lacewings, ground beetles, flies, and wasps,” adds Brook. “In the true bugs, the names tell the story. Pirate bugs, ambush bugs, assassin bugs, and stink bugs attack and suck the juices out of aphids and other problem insects. Another true bug, damsel bugs are important predators of diamondback moth larvae. In one greenhouse study, a single damsel bug ate 131 eggs or 95 larvae in a 24 hour period.”
“Ground beetles are a large group of insects that help out in the field, are usually more active at night, and will attack almost anything they can overpower. Different ground beetles eat cutworms, potato beetles, root maggots, diamondback moth larvae, wheat midge larvae, and eggs of pest species. Some species of ground beetle feed on weed seeds. One well-known star of biocontrol is the lady beetle. Both the adult and larvae of the beetles like to eat aphids,” says Brook.
Brook says that not all flies are a problem. After bees, hover flies are the second most important group of pollinators. They are often mistaken as wasps or bees. Larvae of many fly species prey on aphids, thrips, and other crop feeding insects. In the soil, stiletto fly larvae feed off the larvae of other pests such as wireworms.
Same goes for wasps, Brook adds. “Wasps are important for parasitizing larvae of bertha armyworm, aphid, cereal leaf beetle, and diamondback moth. There are many wasp species that are very good at reducing pest species populations.”
“In agriculture, we tend to concentrate and worry about those factors that have the potential to damage yield potential in our field crops,” mentions Brook. “We also need to get informed about those insects that are working on our behalf. Just counting pests only gives an incomplete picture. With an idea of beneficial insect populations and activity, you can make better decisions on using insecticides when and where they are needed. Avoid the situation where you kill more of your beneficial than the pest species.”
Register for the Alberta Agriculture and Forestry webinar on beneficial insects happening Tuesday, March 20, at 10 a.m. featuring John Gavloski, provincial entomologist with Manitoba Agriculture. This webinar will be recorded, but Brook adds, “By attending, you have the added advantage of being able to ask Gavloski questions related to his area of expertise.”
For more information, contact the Alberta Ag-Info Centre at 310-FARM (3276).
Three crop varietal factsheets have been posted to the Alberta Agriculture and Forestry website to help producers make sound decisions when deciding which varieties to grow.
“Varieties of Cereal and Oilseed Crops for Alberta (http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex4069) provides information on cereal and oilseed variety performance within Alberta and northeastern British Columbia,” says Alex Fedko, crop research technologist, AF. “Important agronomic characteristics and disease resistance information are provided for varieties of wheat, barley, oat, rye, triticale, flax and canola.”
Varieties of Pulse Crops for Alberta (http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex3795) provides information on pulse variety performance within Alberta and northeastern British Columbia. Important agronomic characteristics and disease resistance information are provided for varieties of field pea, chickpea, lentil, faba bean, dry bean, and soybean.
“An important component of the annual feed supply for Alberta’s cattle producers comes in the form of silage, green feed and swath grazing,” says Fedko. “As evidenced in Silage Varieties for Alberta (http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex14708), the selection of varieties that produce the highest forage yield and/or nutritional quality becomes increasingly important.”
View a listing of all the crops publications here. Hard copies of the factsheets are available to Alberta residents by using the online order form or by calling 780-427-0391.