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ARS Home » Pacific West Area » Logan, Utah » Pollinating Insect-Biology, Management, Systematics Research » Research » Publications at this Location » Publication #334845
Title: Wildflower plantings do not compete with neighboring almond orchards for pollinator visits

Author
item LUNDIN, OLA - University Of California
item WARD, KIMORA - University Of California
item ARTZ, DEREK - Former ARS Employee
item Boyle, Natalie
item Pitts Singer, Theresa
item WILLIAMS, NEAL - University Of California

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/12/2017
Publication Date: 4/4/2017
Citation: Lundin, O., Ward, K.L., Artz, D.R., Boyle, N.K., Pitts Singer, T., Williams, N.M. 2017. Wildflower plantings do not compete with neighboring almond orchards for pollinator visits. Environmental Entomology. doi:10.1093/ee/nvx052.

Interpretive Summary: Planting flowering agricultural field borders has emerged as a research and policy priority to help alleviate threats to pollinators. Studies have, however, rarely addressed the potential that flowering field borders might compete with neighboring crops for pollinator visits if they both are in bloom at the same time, despite this being a concern expressed by growers. We evaluated how wildflower plantings added to orchard borders in a large commercial almond orchard (512 ha) affected honey bee and wild bee visitation to orchard borders and the crop. The study was conducted over two consecutive seasons using three large (0.48 ha) wildflower plantings paired with control orchard borders in a large (non-diverse) agricultural landscape in California. Honey bee and wild bee visitation to wildflower plots were much higher than to control plots, but increased honey bee visitation to wildflower plots did not lead to any detectable shifts in honey bee visitation to almond flowers in the neighboring orchard. Wild bees were rarely observed visiting almond flowers irrespective of border treatment, indicating a limited short term potential for supplementing crop pollination using wild bees in this landscape. Our study indicates that growers can support bees with alternative forage in almond orchards without risking competition between the wildflower plantings and the crop.

Technical Abstract: The engineering of flowering agricultural field borders has emerged as a research and policy priority to mitigate threats to pollinators. Studies have, however, rarely addressed the potential that flowering field borders might compete with neighboring crops for pollinator visits if they both are in bloom at the same time, despite this being a concern expressed by growers. We evaluated how wildflower plantings added to orchard borders in a large commercial almond orchard (512 ha) affected honey bee and wild bee visitation to orchard borders and the crop. The study was conducted over two consecutive seasons using three large (0.48 ha) wildflower plantings paired with control orchard borders in a highly simplified agricultural landscape in California. Honey bee (Apis mellifera L.) and wild bee visitation to wildflower plots were at least an order of magnitude higher than to control plots, but increased honey bee visitation to wildflower plots did not lead to any detectable shifts in honey bee visitation to almond flowers in the neighboring orchard. Wild bees were rarely observed visiting almond flowers irrespective of border treatment, indicating a limited short term potential for augmenting crop pollination using wild bees in this landscape. Our study indicates that growers can support bees with alternative forage in almond orchards without risking competition between the wildflower plantings and the crop.