Honey bees still lift yields in self-fertile almond orchards, but growers may not need the usual two hives per acre, according to a two-year study supported by the Almond Board of California and reported by California Ag Network. Hive rental is one of almond growers' biggest annual costs: the standard recommendation for a mature orchard is two hives per acre at about $200 a hive.
The study in the self-fertile Independence variety, run in 2020 and 2021 by researcher Nino with Arathi Seshadri of USDA-ARS, Zac Ellis of Olam and Angie De La Luz of Beeflow, first caged some trees to keep bees out. Trees open to bees set significantly more nuts and gave higher yields and heavier wet and dry weights, although average kernel mass was slightly lower, as the tree spread its resources over more nuts.
In the second year the team compared zero, one and two hives per acre, assuming ambient bees from neighbouring orchards equal to about half a hive. Bee activity rose from no hives to one hive, but going from one to two hives brought no significant increase in flower visits, and too many bees can damage flowers. "Between one hive and two hives, there was actually no significant difference," Nino said.
The result is an economic choice: growers must weigh the extra yield against the cost of renting hives. The researchers say the study was small and more work is needed as more self-fertile varieties reach growers.
Photo: Almond Board of California
Source: California Ag Network
Comments
(0)