by Dewey M. Caron, Communications and Content Specialist for the Oregon Master Beekeeper Program
Best Bees
Are you looking for “talking points” about Bees? For a presentation perhaps or to entertain friends and family? Good solid information about bees. Bruce Rutter and Elsa Scott of Best Bees have gathered 155 Amazing Facts about Bees and Beekeeping, organized into categories such as: History, Mythology, Folklore; Famous beekeepers, Bee Anatomy and Lifecycle, Facts about queens, drones pollination, honey and more. Many have further information referenced from previous Best Bees blogs. A treasure trove of bee facts. https://bestbees.com/2023/02/08/bee-facts/?utm_source=newsletter&utm_medium=email&utm_campaign=oct-newsletter-3&utm_source=The+Best+Bees+Company&utm_campaign=19b3416f88-OCT_NEWSLETTER_THREE_17_10_24&utm_medium=email&utm_term=0_60dea9f9db-055fa2c440-%5BLIST_EMAIL_ID%5D
Potential interactions between acids and amitraz in controlling varroa mites
A major concern for beekeepers globally is effectively controlling Varroa destructor mites. These mites are well-known for their role in weakening bee colonies, spreading viruses, and contributing to colony collapse. A fall memo from Veto-Pharma cautions beekeepers on combining varroa controls of oxalic and formic acid and amitraz. They indicate the combination of these treatments requires “careful consideration due to potential interactions that can affect their efficacy”.
Data indicates acid-based controls may create a highly acidic environment in the bee hive, which can interact with timed-released treatments of amitraz strips. Such negative interaction can occur at the end of the season when using formic acid for quick ‘knock down of varroa mites or when multiple oxalic acid seasonal vaporizations have been used. Not included is reference to dribble oxalic acid or extended release of oxalic acid, which has not been “legal” until recent release of the product VarroxSan. The observation suggests that the acidic environment created by oxalic acid could degrade amitraz, thereby reducing the effectiveness of the treatment.
They list 4 key considerations for effective Varroa mite control:
- Sequential treatments: Rather than applying amitraz strips and oxalic acid vaporization simultaneously, consider using them sequential. For example, you might treat the hive with amitraz strips first, allowing sufficient time for the treatment to take effect before applying oxalic acid. The mode of action of some active substances is not completely understood, so it is not recommended to apply multiple treatments simultaneously to avoid undesirable effects.
- Treatment timing: Pay attention to the timing of treatments. Amitraz strips are often used during the brood-rearing season, while oxalic acid is typically more effective during brood less periods (e.g., late fall or early winter). By aligning treatments with the colony’s natural cycles, you can maximize their effectiveness.
- Monitoring and assessment: Regular monitoring of mite levels is crucial for assessing the effectiveness of your treatment plan. Use tools such as sticky boards, alcohol washes, or powdered sugar shakes to measure mite infestations before and after treatments. This data can help you make informed decisions about treatment adjustments.
- Integrated Pest Management (IPM): Employ an integrated pest management approach that combines chemical and non-chemical methods. This might include brood breaks, requeening, drone brood removal and timely colony splitting. Additionally maintaining strong, healthy colonies through proper nutrition and management practices.
Monitoring restoration efforts using honey bees
Belgian company BeeODdiversity has enlisted several beekeeper members of the Klamath Basin Beekeepers Association in using honey bees to aid in monitoring of riparian and wetland restoration. Honey bee foragers monitor biodiversity and agricultural and industrial pollutions via their BeeOmonitoring program which measures the state of plant biodiversity, pesticides, nitrates, heavy metals, PAHs and other pollutants. https://beeodiversity.com/en/
CBS Saturday Morning News of Saturday November 8th featured retired surgeon, now conservation Farmer, Dr Karl Wenner and BeeODiversity spokesperson Michael van Cutsem. Dr Wenner traps pollen from his 4 colonies and the Belgian company does the lab analysis. Dr Wenner, along with other landowners and monitoring on Nature Conservancy, an abandoned mill site and tribal lands in the County, has been able to document the beneficial changes to restored areas. https://www.facebook.com/watch/?v=2531254837057172
New varroa control chemicals + use of heat
There are two new formulations of varroa control chemicals. Amiflex is registered for use in Oregon. It is OAE – Oxalic Acid extended. The product is acid impregnated cardboard strips designed to be hung over frames. Up to 6 strips might be used per hive depending upon colony size and treatment is 4 to 8 weeks. Currently, the only packaging is 80 strips sold in a non-resealable package. There may be a 20-strip product available by next year.
The second chemical is AmiFlex (EPA Reg. No. 87243-4). The chemical is amitraz designed as “flash treatment”. It too is registered in Oregon but is a Restricted Use Pesticide (RUP), so it may only be sold to and used by “certified applicators or persons under their direct supervision, and only for those uses covered by the certified applicator’s certification. (https://oda.direct/PesticideProductSearch).
Heat – several insulated hives, including HiveIQ among hives relatively new on the market, use language in their advertisement that an insulated hive helps in varroa (or more generally pest) control, improves bee health, reduces stress, etc or language to that effect. The concept is mites prefer cooler temperatures for optimal development (think drone brood at margins of the brood cluster location). The argument follows that higher bee nest temperatures, courtesy of insulated hives, are less favorable for mite reproduction. Such claims lack solid research to provide proof of this concept but there are testimonials of beekeeper using such hives reporting less “issues” with varroa mites.