Pollination studies involving zero, one and three colonies of honey bees per acre, on commercial alsike clover fields ranging in size from 15 to 75 acres, were conducted in 1954, 1955, and 1957 in the Hinton Trail district of the Peace River Region of Alberta. These studies indicated that in large fields one colony of honey bees per acre is sufficient to pollinate alsike clover, consideration being given to competition of other crops and to the climatic conditions. The influence of competing crops was such that 65- to 75-acre fields, with one colony per acre, were similar in honey bee populations and seed production to 15- to 20-acre fields with three colonies per acre. Competing plant species accounted for 15 to 36 per cent of the pollen collected by honey bees. Fields with the higher populations of pollinators matured earlier than fields deficient in pollinators. A population of 3400 honey bees per acre (0.7 bee per sq. yd.) throughout the flowering period resulted in seed sets up to 82 per cent and seed yields to 375 lb. per acre. Check fields, where no honey bees were supplied, ranged in production from 29 lb. per acre, with a low native pollinator count, to 293 lb. where a pollinator equivalent of 1300 bumble bees per acre was observed. Bumble bees worked alsike clover at the rate of 28.6 florets per minute, as compared to 20.0 for leaf-cutter bees and 18.7 for honey bees.
Butterflies of the Peace River Region of Alberta and British Columbia
