Abstract: Field investigation show that the alfalfa leafcutter bees dispersed around their beehives. The dispersal and pollination effect decreased with the distance, and differed with direction. High, middle and low effective areas were defined with seed yields of ≥50, 50～30, 30～15g·m^-2, respectively. In high and middle effective areas, the dispersal distances in northeast direction were the longest, with 50 and 60 m respectively, and next by east and north directions. In low effective area, the dispersal distances in north direction was the longest, with 100m, next by northeast, northwest, west, south, southwest and southeast directions. Based on the above results, a map with high, middle and low effective areas of alfalfa leafcutter bees pollination were drawn, from which, the ranges of these three areas could be directly seen.

Key words: Alfalfa leafcutter bee, Pollination, Dispersal behavior