Research shows that honey bees properly nourished with a diverse diet are better able to fend off stressors, such as pests and parasites leading to stronger hives.
Almond grower Nick Edsall believes that improving the diet of pollinators by providing cover crop forage in his orchard middles also improves pollination.
“The almond pollen provides good food for the bees, but it’s always good to have a balanced diet for bees as it is for humans, Edsall said. “If you can have other food sources out there it strengthens the colonies, so it helps crop pollination while helping improve the health of colonies at the same time.
Edsall this year planted forage cover crops in about 5% of the 4,500 acres of almonds he manages for Bullseye Farms in Woodland, Calif. The trial went so well, he plans to expand that acreage next year to about 20% of the total acreage.
He originally looked at cover crops to improve water penetration on challenging fields, planting triticale last fall to improve soil health on heavy clay soils.
“In those fields, we had a lot of cracking and actually lost a lot of nuts in cracks at harvest and had a hard time making adjustments with our sweepers. We planted triticale and it made a big difference, so we were looking at expanding our use of cover crops,” Edsall said.
After hearing about the Seeds for Bees program through Project Apis m. (PAm), Edsall decided this season to explore cover crop mixes that would provide the additional benefit of providing flowering forage for honey bees in the periods surrounding almond bloom – specifically before and after when there is a shortage of forage.
PAm has identified low-moisture-requiring seed mixes, seed suppliers, and planting regimes for various California climates specific to bee habitat in almonds, including specially blended mustard mix for fall and winter bloom and clover mix and lana vetch for spring bloom. It works with seed suppliers in bee growing regions throughout California to provide specially blended bee forage mixes that match individual growers’ operations and objectives. PAm also provides technical advice for growers looking to get started on a bee forage cover crop program.
One of Bullseye’s beekeepers provided the added benefit of discounting the cost of hive rental because forage was planted.
“It all kind of worked together for us. We understand how important pollinators are for the almond crop, and this was an opportunity to plant crops for soil health and water penetration while also feeding bees when they arrive in late winter,” Edsall said.
He planted about 100 acres of vetch and 60 acres of clover mix, along with a few rows of mustard-radish mix last October. Edsall said he wanted to trial the mustard on a few rows first to be sure excess biomass wouldn’t create problems interfering with orchard operations in spring or fall harvest. Even with all this year’s rain, by late July Edsall found that wasn’t the case.
“We planted with a seed drill in October and got plenty of moisture to bring the crop up. Then we had a wet spring to keep the cover crops going,” he said. “We had plenty of moisture so we didn’t have to worry about the cover crops drying the soil, and actually saw a benefit in keeping the soil from getting too saturated so we could get our equipment on the ground a little earlier with the cover crop holding the soil together.”
Edsall also saw distinct benefits in water penetration on those heavy clay fields and even after bees were removed he saw several wild bees continue to fly around those cover crop orchards. Bullseye Farms mowed the cover crops early in the season two to three inches above the ground to keep growth under control. The crop still pushed flowers in the spring. To terminate the annual crops, Edsall mowed a couple more times starting in mid-May very close the ground.
“We had worried about competition of cover crop when almonds bloom, but we are seeing research that shows bees actually prefer the almond pollen so they are collecting almond pollen in the morning and forage in the afternoons once almond pollen has been worked,” he said. “Having cover crops out there blooming seems to help the pollination of the crop, whether colonies are stronger because of a balanced diet or bees are working harder.”
This year’s crop went so well Edsall plans to increase plantings this fall with a cover crop rotation that includes alternate rows of triticale in one row and legumes or mustard on alternate rows.
“We had a good experience and are excited this fall to try doing much more with cover crops in our almonds. It’s another crop out there so you have to take time to manage it, and it takes a little extra effort, but the benefits seem to be well worth it for us.”
More information on resources for planting bee forage in almonds can be found on the PAm website at ProjectApism.org. Additionally, visit Almonds.com/Pollination for more ways that almond growers can benefit honey bees year-round.
