Hornfaced Bee

The hornfaced bee, also known as the orchard bee (Osmia cornifrons) is named for the prominent horn-like prongs located on the lower part of its face. The hornfaced bee is brownish-colored with light stripes on the abdomen. Males are smaller than females and have long antennae. These bees are native to Japan, but were introduced to the United States in the 1970's. Populations are now established on the east coast and in the mid-west. These bees nest in hollow reeds or grasses.

Hornfaced bees are solitary nesters; each female bee mates, builds a nest, and lays eggs. These bees are gregarious, preferring to nest in groups. Hornfaced bees emerge in early spring, with males emerging a few days before females. The bees mate and then females begin building nests and laying eggs. Adults die in late spring or early summer, after being active for about four to eight weeks. Larvae hatch in the fall, spin cocoons, turn into pupae, and then adult bees. The adult bees become dormant and remain so until they emerge in early spring.

In Japan, hornfaced bees have been used since the 1960's as commercial pollinators of apple (Malus domestica) and cherry (Prunus spp.) trees. Currently, these bees are used to pollinate 75% of Japan's apple orchards. Since their introduction to the United States, the hornfaced bee has been managed to pollinate fruit orchards, particularly apple trees. Currently research is being conducted to determine if these bees could also be used as commercial mustard seed (Brassica spp.) pollinators. In addition to managed crops, hornfaced bees also pollinate ornamental plants like crabapple (Malus spp.) and bush honeysuckle (Diervilla spp.). Hornfaced bees are particularly attractive as commercial pollinators for several reasons. These bees are relatively easy to handle, because they are mild-tempered and non-aggressive. They are easy to manage; in the wild, they are solitary ground nesters, but they adapt to artificial nests made of cardboard tubes and wood blocks. Population size doubles or triples yearly, depending on the number of nest sites available. Hornfaced bees are also efficient pollinators, even more so than honey bees in some instances. Both male and female hornfaced bees visit and pollinate flowers; in honey bee populations, only female worker bees collect pollen. Hornfaced bees will fly in cool and cloudy weather, unlike honey bees. So far, hornfaced bees are unaffected by the mites and diseases that are currently affecting honey bee populations. Additionally, studies have shown that hornfaced bees spend more time per flower and do a more thorough job of pollination than honey bees (Apis mellifera). Finally, far fewer hornfaced bees than honey bees are needed to provide pollination services - depending on the crop, about 250-400 nesting hornfaced females per acre are required whereas one strong hive, between 25,000 and 30,000, of honey bees per acre are required.