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.
Honey Bee Management
Honey Bee Health Stewardship
The decline of honey bee health has been put in the public spotlight. Almonds rely on honey bees for pollination, and the California Almond community recognizes the essential role bees play in sustaining the global food supply.
The Almond Board of California has invested more money in bee research than any other U.S. commodity. The results of this research are being used to improve best management practices for both growers and beekeepers.
A report from the National Stakeholders Conference on Honey Bee Health, held in 2012, separates the issues that impact the overall health of bees into four main categories:
The Almond Board has invested nearly $1.3 million in honey bee health research since 1995 in the following four areas. In more recent years, the primary focus of this research has been healthy hives, which includes:
Improving honey bee nutrition
Effective management of bee pests and diseases
Improving honey bee breeding stock
Assessing impacts of pesticides used in almonds
The Almond Board, in collaboration with Project Apis m., USDA, the University of California, beekeeper organizations and other groups, has supported and continues to support research to develop best management practices in these areas for growers and beekeepers alike. A key goal is to ensure almond orchards continue to be a good, safe place for honey bees to forage — a place that keeps them healthy and where hives increase in size.
Key areas of research and outreach are:
Improving genetic diversity in honey bees to enhance resistance to pests and diseases, and transferring that technology to bee breeders for integration into commercial breeding stock;
Cooperating with Project Apis m. and others to encourage almond growers to provide blooming plants, or “bee pasture,” as food sources of honey bees before and after almond bloom. Continual and diverse food sources promote bee health and thereby improve pollination;
Developing tools to control Varroa mites and other bee pests;
Understanding the potential impact of pesticides used in almonds on honey bee development;
Developing in-hive supplemental diets for bees, which are used when natural pollen sources are at a low ebb; and
Supporting outreach, or technology transfer teams, that have implemented diagnostic and integrated pest management (IPM) programs for beekeeping operations, resulting in better control of beehive pests with fewer chemicals.
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.