Issue link: http://read.dmtmag.com/i/57720
Pollen-laden honeybees visit peach and nectarine blossoms. must be enough bees to move the pollen throughout the orchards. If honeybee colonies are of adequate strength (in frames of bees), most crops can be pollinated adequately with one colony per acre. With smaller orchards (40 acres or fewer), peripheral placement of colonies should be adequate. With larger orchards, some of the hives should be distributed throughout the orchard as well as around the periphery. Honeybees foraging for nectar are apt to begin in the morning and continue foraging throughout the day, if nectar is constantly produced. Pollen foragers will begin collecting pollen when the moisture conditions are appropriate. This may be a bit later in the morning. Usually, pollens are liberated (dehisced) from the anthers early in the day. Often, bees can remove all the pollen in a few hours. Thus, pollen foragers will be in the flowers only until the pollen has been removed for the day. Pesticides Pesticides of various types, especially fungicides, are likely to be used during bloom to protect the flowers from diseases that may enter and blast the flowers, ruin the fruit, or spread diseases into the branches. Even if you carefully read the precautions on fungicide labels, you will not know if the fungicides might be harmful to bees. This is because the reg- istration process requires only a 24- or 48-hour mortality test on adult honeybees. Fungicides do not kill adult honeybees quickly. In fact, adult bees probably will not be negatively affected by fungicides at all. How- ever, when the fungicides carried on incoming pollens get mixed into the food chain of the colonies, they can have detrimental impacts on the brood. Often, depending upon concentrations fed to the larvae, the lar- vae may simply die, or the larvae may continue to feed and grow. Prob- lems can occur when the pupae try to chew out of their cells and become functional adults. Again, depending upon the dose, new adult bees can fail to emerge completely. They stick their heads out of the cells and extend their mouthparts as if soliciting for food. Some emerge with distorted body parts. They will be useless to the colony and will not live very long. The best way to protect pollinators from negative effects of exposure to pesticides is to refrain from spraying any pesticide on the pollen-laden flowers or the pollen-collecting bees while the bees are foraging, which usually occurs early in the day. If you visit the orchards and look for pollen foraging, you can determine the safest time for spraying. • Queen bees lay eggs singly in cells of the honeycomb. After the eggs hatch, worker bees feed the larvae in the cells and cap them when the larvae pupate. A drone is pictured emerging from a cell. GOOD FRUIT GROWER MARCH 15, 2012 13 PHOTOS BY KATHY KEATLEY GARVEY, UC, DAViS.