Location: Pollinating Insect-Biology, Management, Systematics Research
Project Number: 2080-21000-019-068-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 1, 2023
End Date: Jul 31, 2025
Objective:
Objective 1 Document the wild bee community visiting flowers of small fruits (blueberries, strawberries, currants, and raspberries)
Objective 2 Test different ‘bee condo’ rearing materials to determine the best condo design to deploy for each Osmia species.
Objective 3 Use behavioral observations and pollen identification from Osmia lignaria, O. ribifloris, and O. bruneri nests to determine crop visitation rates, pollen preferences, and nesting rates of the bees.
Objective 4 Test different stocking densities of the three Osmia species and measure the reciprocal crop yields
Objective 5 Provide recommendations to Utah small fruit growers, and other growers of these crops, on the use of Integrated Crop Pollination practices—such as the use of alternative managed pollinators Osmia lignaria, O. ribifloris, and O. bruneri.
Approach:
Small fruit crops such as blueberries, strawberries, currants, and raspberries greatly benefit from animal-mediated pollination. However, the pollination needs of these crops in Utah are understudied. Additionally, the reliance on honey bees alone for crop pollination can result in low yields due to a mismatch in pollinator efficacy (honey bees are not always the best pollinator for some crops) or poor health of honey bee hives. Contracting with commercial beekeepers can also result in substantial production costs for growers. Therefore, researchers will investigate two important components of an Integrated Crop Pollination system for these crops in Utah, including promoting pollination from wild bees, and use of alternative managed pollinators. With this integrated approach, growers can decrease pollination costs and increase yields.
Researchers will document the bee community visiting these crops to determine the primary pollinators. Bee communities will be documented by doing timed observations at crop flowers to estimate relative abundances of groups of bees, followed by timed sampling (netting) of bees at flowers to identify bees to species. Bees will be identified at the USDA ARS Pollinating Insects Research Unit (USDA PIRU) and specimens held at the U.S. National Pollinating Insects Collection (Logan, UT).
Researchers will also test stocking densities, behavior, and predilections of three managed solitary bees native to Utah, Osmia lignaria, the blue orchard bee, O. ribifloris, and O. bruneri. To determine the efficacy of O. lignaria, O. ribifloris and O. bruneri for these crops, adults of all species will be released during bloom and nesting condos placed throughout the crop field. Nesting rates in different condo substrates will also be assessed in order to optimize the condos used for each species. Visitation to crop flowers will be monitored through observations in the field, and through the comparison of pollens found in completed bee nests to pollens extracted from crop flowers. Pollen identification allows for the determination of plant preferences for these species, thus informing its usefulness as a managed pollinator for each crop. For crops where these bees show particular promise as managed pollinators, stocking densities will be evaluated (how many adult males and females are released per acre of crop).
