Package bees and small hives have proven inferior to strong overwintered colonies for pollination of early-season crops. The field bee population generally is correlated with the amount of brood in the hive. In packages and weak colonies, too many bees must remain in the hive to keep it warm and raise the brood. Two weak colonies do not equal one strong colony. Colonies used for springtime pollination should be queenright, one and a half or two stories high, with four to six frames of brood and enough adult bees to cover six to eight frames.

Beekeepers who rent weak or dead colonies of bees tarnish not only their own reputation but also that of other beekeepers in the state. Beekeepers who rent bees should attempt to develop colonies into the most efficient pollinating units in time to do the job. Some growers may ask beekeepers to open a few randomly selected colonies to demonstrate colony strength.

The rule of thumb for most crops is to start with one colony per acre. If the area is already well populated with wild bees and honey bees, as in many areas of Pennsylvania, the number of colonies may be reduced. If the weather is so cold or wet as to restrict bee flight, more bees may be put in the crop. The number of colonies needed will vary with location, attractiveness of the crop, density of the flowers, length of the blooming period, colony strength, and competitive plants in the area.

Because the activity of bees is determined to a great extent by the temperature and conditions within the hive, location in the orchard is very important. Place hives where they are protected from the wind and where they are exposed to the sun from early morning until evening. If such a spot is not available in or near the orchard, it is worthwhile to make one. A stack of boxes or bins makes good protection if located properly.

Distribution of single colonies throughout a field or orchard is time consuming, expensive, and unnecessary. Placing colonies in groups of four to eight in favorable locations throughout a field or orchard can provide even distribution of bees. Pollination will likely be just as effective in many large orchards if groups of ten to twenty hives are strategically distributed in sunny, wind-protected spots well within the boundaries of the orchard.

Weather is the key to maximum use of the pollinating force. Bees rarely fly when the temperature is below 55° F or the wind is more than 15 to 20 miles per hour. The stronger the colony, the lower the temperature at which the bees may initiate flight. Strong colonies do little pollinating below 55° F and weak ones do little below 60° F. Cool cloudy weather and threatening storms greatly reduce bee flights. The poor weather, bees foraging at more distant locations will remain in the hive and only those that have been foraging nearby will be active. Therefore, over an extended period of inclement weather, colonies may require greater distribution to get adequate coverage.

Bad weather also presents hazards to the plant. Spring frosts can kill fruit bloom, and temperatures of 40° to 50° F retard pollen germination and tube growth. Fertilization failure may result. If the weather is hot and dry or windy, stigmas may dry out so that deposited pollen does not germinate. Pollen release may be hindered by prolonged rains.

Effective pollination can take place with surprising rapidity in warm clear weather.