A three-year study has shown that squash bees and wild bumblebees are just as capable of pollinating the same amount of pumpkins for commercial growers as the honey bees they rent to do the job. The new study was published in the Journal of Economic Entomology. These wild bees were more than capable of handling the pollination of a full yield of pumpkins and these bees are free of charge.
This pumpkin study in Pennsylvania was part of the Integrated Crop Pollination Project, headquartered at Michigan State University and funded by the US Department of Agriculture’s Specialty Crop Research Initiative. The larger project assessed the ability of pollinators across the USA to pollinate cherries, almonds, blueberries, watermelons and pumpkins.
This 3:12-minute video gives a bird's eye view of squash blossom pollination:
The Penn State research indicated the top three pollinators, responsible for more than 95% of the pumpkin pollination of the 30 pumpkin fields, were honeybees (Apis mellifera), the common eastern bumblebees (Bombus impatiens) and squash bees in the genus Eucera.
Since honeybees need to visit a flower 8-15 times to accomplish pollination, the team was blown away to observe that bumble bees and squash bees can do the job in half the number of visits, due to their clumsy super-fuzzy bodies that carry at least double the pollen of a honey bee or squash bee. They leave more pollen behind on the flower. In fact, they were doing 10 times the pollination of the honeybee.
This discovery indicates that wild bees are super-star pollinators and that it isn’t necessary to hire honeybees. This may impact how commercial growers look at the matter over time. For instance, one grower cut his honey bee rentals from one hive per acres to one hive per two acres. The outcome did not reduce his pumpkin yield.
The purpose of the study is not to advise growers to drop honeybees completely. It is to encourage them to think about the best way to bring a pollinator community to their fields, and sometimes that may favor wild bees. In these times, where inclement weather, disease and other factors can contribute to a bad year, it’s good to know that there are other pollinators out there that can pick up the slack.