Our researchers have begun to collect pollen pellets from honey bees.

A pollen pellet is a clump of pollen grains resulting from a bee’s travels through flowers. As a honey bee visits each flower, she collects pollen grains, mixes them with a little nectar, and packs them onto her hind leg, forming the pellet.

Honeybee with a large pollen pellete on her leg.
Arrow points to the pollen pellet on a honeybee's leg.

To determine which environmental horticulture plants bees visit, researchers can use pollen pellets to identify plant pollen contained within the pellets.

To begin identifying plants by pollen, our researchers have placed honey bee hives at three environmental horticulture nurseries in Connecticut and at various residential/commercial areas around Philadelphia, Pennsylvania.

Each hive has a pollen trap installed, which knocks off pollen pellets when bees pass through the traps to enter their hive. The fallen pellets are stored in a basket until collected by the researchers.

A pile of many clumps of pollen spread out on a wire mesh screen.
Various pollen pellets collected from a pollen trap.

To find out which plants honey bees have visited, a palynologist—someone who identifies pollen and spores by their color and unique structures—will prepare the pollen for viewing under the microscrope and match the different shapes of the pollen grains she finds to the plant species they come from. This work will allow us to see which species of environmental horticulture plants the honey bees visited. In addition, these pellets can be tested for pesticides residues.

Researchers: Drs. Christina Grozinger, Harland Patch, Douglas B. Sponsler, and Kim Stoner

States: CT, PA