Where would we be without bees? The arrival of spring reminds us that many of the flowers we depend on to give us fruit or vegetables depend on the honeybee. Among the fruit trees that are largely pollinated by bees are apple, peach, plum, cherry and pear. Blackberry, blueberry, gooseberry and raspberry are also largely dependent on bees for production. The work of bees extends to many vegetable crops which include squash, cantaloupe, watermelon, cucumber, green bean and lima bean.
Even for crops that are largely self pollinating, bees may have some influence. Some of these include tomato and pepper. Workers have found that cross pollination of these crops by bees may increase fruit set in some varieties. The work of bees goes far beyond horticultural plants and also influences production of seeds in alfalfa, clover, lespedeza trefoil, cotton, soybean and sunflower.
Fruit trees without a strong hum of bees in them may not be adequately pollinated. Although it has not been definitely determined, it is believed that one bee is able to pollinate 5,000 flowers per day per tree. Bees work best when temperatures are above 65 degrees F. Incomplete pollination results in excessive fruit drop or even poorly developed fruit which may eventually drop off. Many apple varieties are not self fruitful and must have the pollen carried from another tree of a different variety. Only bees can do an adequate job of carrying pollen from one tree to another.
Although wind is the primary pollinator for important food crops such as wheat, rice, corn, sorghum and other grains, bees are by far the most important pollinators of horticultural crops in the world.
To maintain the productivity of trees and gardens, and also to help the bees, be alert to the bee activity whenever you plan to spray a crop to control a damaging insect pest. Too often, indiscriminate spraying can kill many bees. Treat for pests only when necessary, and at a time of day with less tendency to harm them.
In spring as fruit trees flower, avoid spraying them with insecticides when they are in bloom. Spraying for fruit pests can be done before and after flowering without harm to bees. This is true at all times – do not spray plants that are in flower.
The gardener may say, “What about cucumbers? They flower constantly.” The best time to spray such plants, if needed, is in the very early morning or late evening when bees are not active. Evening may often be better since some plants have new flowers that open during the morning and, therefore, would not have spray residue on them. Liquid sprays rather than dusts are also less likely to be picked up by bees. They drift less and, therefore, can be less damaging.
One of the most widely used insecticides for eliminating many pests is carbaryl (trade name Sevin), which is widely used in flower and vegetable gardens. Although it is one of the less toxic materials in regard to human use, it is highly toxic to bees. Therefore, this pesticide should not be used at any time that bees are active. Use care whenever using any insecticide. Check labels for correct amounts and for any special precautions that should be taken.
Always be aware that bees may be on nearby wildflowers, clover, or other plants near the garden. When spraying plants that are not visited by bees, keep watch for any nearby area where bees may be active. Do not allow the pesticide to drift over them. With caution, there will be better pollination, better production, and better honey for everyone.