The weather is starting to warm up, and that means soon bee hives will be placed in orchards. Growers will need to be careful with almond spraying, to protect the bees. Almond Board Director of Agricultural Affairs, Bob Curtis, says things are little different during a wet year.
The blossoms of nearly all California Almond varieties are self-incompatible, requiring cross-pollination with other varieties to produce a crop. Even self-compatible varieties still require transfer of pollen within the flower. The single most important factor determining a good yield is pollination during the bloom period. About 1.6 million colonies of honey bees are placed in California Almond orchards at the beginning of the bloom period to pollinate the crop. California beekeepers alone cannot supply this critical need, which is why honey bees are transported across the country to the San Joaquin Valley each year.
Treating almond orchards for bloom-time pests, particularly diseases, is important, and fungicide applications are needed in many growing situations. Nevertheless, it is important to minimize exposure of bees and pollen to any spray by avoiding applications when pollen is available and bees are foraging. Furthermore, recent information indicates newer biorational insecticides that have been tank-mixed with fungicides at bloom may impact bee brood (developing larvae).
Along these lines, it is extremely important that pesticide applications at bloom follow these best management practices:
Applications of insecticides during bloom should be avoided until more is known about the impact on bees.
Exposure of bees and pollen to fungicides should be minimized by avoiding applications when pollen is available and bees are foraging; spraying should be done after mid-afternoon or at night.