Alfalfa and Red Clover as Sources of Nectar and Pollen for Honey, Bumble, and Leaf-cutter Bees (Hymenoptera: Apoidea)

Abstract

The most important factor affecting the densities of pollinating species of bees on alfalfa seed fields in southern Alberta is competing flowering growth (Hobbs and Lilly, 1954, 1955). This is a report on the relative attractiveness of red clover and alfalfa to honey, bumble, and leaf-cutter bees in southern Alberta. Observations were made on the first crops grown in each of two newly cultivated and irrigated areas near Hays; the fields were isolated from all other entomophilous crops by at least five miles of virgin prairie. A third series of observations was made on crops grown in the isolated river valley near Lethbridge previously described by Hobbs and Lilly (1955).