Assessing the Impact of Thyme Nectar and Pollen on Honeybee Health

Commodities

• Animals: bees

Practices

• Animal Production: animal protection and health
• Pest Management: disease vectors

This project will explore whether availability of thyme pollen and nectar has a positive impact on bee health.  Varroa mites and the lethal viruses they transmit continue to present a huge challenge for northeastern beekeepers, with Vermont beekeepers losing 30-80% of their overwintered colonies annually over the last decade, mostly to mite pressure. Mite disease have a huge economic impact on beekeepers, both in colony losses and in expenditures for mite treatments, which are often applied multiple times in over the course of a season. 

We propose to compare nosema, varroa mite and virus loads in colonies with and without access to thyme flowers planted on a diversified organic vegetable farm. Thymol, a terpenoid which is present in thyme nectar and pollen, is also the active ingredient (at much higher concentrations) in Apiguard and other commonly used in-hive varroa mite treatments.  Research indicates that chemicals in plant nectar and pollen can improve honeybee viral immunity, and that honeybees can preferentially self-medicate by choosing honeys with higher antibacterial activity. Research at UMass Amherst has shown that increased sunflower pollen availability on a landscape level correlates with significantly reduced varroa mite levels in honeybee colonies. 

The anti-pathogenic activity of thyme is well-documented, and we are curious whether planting thyme on our farm can support the health of our honeybee colonies - and if the bees will visit the flowers, and collect the pollen and nectar. We will also sample neighboring bumblebees and test their virus loads.

This project takes up a question I’ve been curious about as a farmer/beekeeper for years: can pollinator health and productivity be augmented with herb plantings on farms? We will test whether thyme nectar and pollen can positively impact honeybee health and productivity, with a focus on varroa mites and related viruses, by comparing colony health in locations with and without thyme plantings.  This work builds on other studies exploring how anti-pathogenic plant compounds interact with bee health. In order to assess thyme impact on honeybee health, we will collect data including nosema (a spore-forming fungus) and varroa mite counts, varroa-related virus levels, and colony productivity and winter survival. Nectar and pollen will be sampled during bloom and analyzed to confirm that the bees are foraging on thyme. A few secondary objectives will also be addressed, including gaining understanding of how many plants are required to have an impact on bee health, monitoring levels of honeybee viruses in bumblebees (an issue of state and nationwide concern), and developing a low-cost, easy to install and maintain method for interested beekeepers to establish flowering thyme and other herbs in beeyards in 6” pots. We will also learn about floral diversity at study locations.