By Josh Lancette
New research published this week in the journal Environmental Entomology shows that planting wildflowers next to almond orchards does not cause fewer honey bees to visit the orchard. This finding is important because it shows wildflower plantings can help keep bee populations healthy while also not harming almond crops.
“Establishing flowering field-edge plantings has gained popularity as a strategy to mitigate the threats that bee pollinators face in intensively managed agricultural landscapes,” says Ola Lundin, Ph.D., one of the researchers and an author on the paper. “The basic idea is simple: to provide more flowers for bees. Flower plantings can potentially affect pollinator visitation rates in neighboring crops both positively by supporting pollinator populations and attracting them to crops or negatively by distracting them from crops. Growers and practitioners are often understandably concerned that alternative forage blooming concurrently with the focal crop might compete for pollinators and negatively affect crop yield.”
While the concern that wildflowers would pull valuable pollination services away from almond crops is understandable, the study suggests that almond growers can put this particular concern aside. While honey bees (Apis mellifera) did visit the wildflowers, it didn’t detract from the number of bees visiting the almonds. But how can this be?
“We suggest two explanations as to why the wildflowers and almond might not compete for honey bee visits,” says Lundin. “One is that wildflower plantings might increase bee foraging activity overall—crop and non-crop visitation combined—such that visitation to non-crop plants in the borders increases when wildflower plantings are added without affecting crop visitation. The second explanation is that the loss of foragers from the crop to the wildflower plantings might be negligible because the crop resource is large relative to the non-crop resource.”
Planting wildflowers next to almond orchards might also be good for the bees.
“The high honey bee visitation rates to the flower plantings suggest benefits of wildflower plantings for honey bees,” said Lundin. “Such benefits may include the ability to support or increase bee population sizes before and after almond bloom and increased resistance to harmful effects of pesticides and pathogens through a more diverse diet.”
Interestingly, wild bees were rarely found visiting the almond orchard, regardless of whether wildflowers were planted or not, a finding that Lundin said indicated “a limited potential for augmenting crop pollination using wild bees in the highly simplified agricultural landscape where we performed the study.”
Josh Lancette is manager of publications at the Entomological Society of America.