Treatments

Project Apis m. – New Data on Spring Colony Losses: USDA-ARS Report

USDA-ARS has released critical findings from the pathogen analysis of samples collected during this spring’s colony losses—and the results are sounding alarms.

New research from the U.S. Department of Agriculture’s Agricultural Research Service (USDA-ARS) sheds light on the causes behind the catastrophic honey bee colony losses reported by commercial beekeepers earlier this year. The findings point to alarmingly high levels of viral infections—vectored by Varroa destructor (Varroa) mites with resistant genes to a common treatment—as key drivers of colony collapse.

🔬 Viruses vectored by Varroa mites were a major factor, and every mite tested carried genes associated with resistance to Amitraz, one of the most commonly used Varroa treatments. This underscores a growing concern within the beekeeping and research communities: the declining efficacy of one of the most widely used Varroa treatments. Thanks to the hard work and urgency of the researchers involved, these results were collected, analyzed, and written up for publication quickly—despite other USDA delays, providing critical information that will help shape how we respond to this ongoing challenge.

Extended Release Oxalic Acid Treatment

Overview

Status

The Extended Release Oxalic Acid Treatment (OAE) is approved by the EPA on a limited basis. Please read here for more information. 

EPA and Approved Treatments

Please decide for yourself how and when you will use OAE. Based on the following, it seems the EPA has removed concerns about OAE use with honey supers.

As per above, the EPA recently established an exemption from the requirement of a tolerance for residues of oxalic acid on honey and honeycomb:

“This regulation eliminates the need to establish a maximum permissible level on these commodities for residues of oxalic acid. Consequently, it is now authorized to use Api-bioxal year-round, including when honey supers are in place.”

Background

Randy Oliver is arguably the expert on Extended Oxalic Acid (OAE) treatment. Randy is a world-renowned speaker, educator, bee biologist, leading researcher, commercial beekeeper, and regular contributor to the American Beekeeping Journal. He is one of the premier beekeeping speakers in the U.S. and the owner/author of http://scientificbeekeeping.com.

 

“Beekeepers worldwide are caught between a mite that has proven able to rapidly develop resistance to synthetic miticides, and the slow pace of development and adoption of mite-resistant bee stock – the eventual solution to varroa.  During the interim, by choice or lack of alternatives, beekeepers are shifting to the use of “natural” treatments.  Oxalic acid (OA) is one of the most promising of those treatments, but its efficacy is limited unless applied during a broodless period. An extended-application method would free it from that limitation. The problem with oxalic acid is that either of the currently approved application methods (dribble or vaporization) kills mites for only about three days.  So unless applied during a broodless period, or repeated at 4-day intervals, oxalic is not very effective over much of the season, due to a proportion of the mites being protected in the sealed brood.  By creating an extended-release formulation, we may have found a treatment that is “natural,” suitable for organic approval, safe for the applicator, non-contaminating of honey, shows no noticeable adverse effects upon the colony, as well as being inexpensive and highly effective at reducing mite populations.” We will refer Extended-Release Oxalic Acid treatment as OAE.

 

Here are some links to his work and recommendations:

We will be following his latest recommendations here.

Materials

OAE is a very inexpensive treatment, but you need some gear to safely and accurately make it. Here’s what has worked well for me:

Equipment

Induction Cooktop

Provides a safe, no-flame way to heat up the solution. The cooktop surface does not get hot during use, as the heat is induced directly into the pan. One less thing to worry about.

Amazon

$70

Digital Kitchen Scale

To weigh the Oxalic Acid and Glycerin.

Amazon

$29

1/3 Size Pan 6″ Depth

Double boiler to safely heat and mix the OA solution.

Amazon

$14

1/3 Size Pan 4″ Depth

Double boiler to safely heat and mix the OA solution.

Amazon

$14

Kitchen Tongs

Mixing the solution and bathing the pads.

Amazon

$9

Do not let OA solution splash into your eyes. It is a guaranteed trip to the ER. I highly recommend wearing a face shield. I find them more comfortable than goggles, and they protect more of your face. If you do use goggles, make sure they fit tightly against your skin. Please do not use safety glasses – get tight fitting goggles or a face shield. Wear disposable rubber gloves.

Face Shield

Protect your eyes and face!

Amazon

$16

Supplies

SpillTech Universal Maximizer Pads 15″ x 19″

This is a large quantity of Randy Oliver’s preferred pad material. GBA may make a purchase of these, so you may be able to get a smaller quantity through the club. A good alternative are Swedish Dishcloths, available from Walmart.

Amazon

$80 for a pack of 100. This is enough to make 800 pads (2 pads per dose). 

$0.20 per dose

Oxalic Acid

The key ingredient. Handle with care – OA is toxic and very acidic. Always wear gloves, eye protection, and a mask.

Amazon

$16 / 2 lbs. Two pounds will produce 20 doses.

$0.80 per dose

Vegetable Glycerin

Used to dissolve the OA and adhere to the pads. Best measured by weight. 

Amazon

$28 / 1 gallon. Smaller quantities are available. This is enough for 80-90 doses.

$0.35 per dose

Startup Costs

Equipment: $152
Supplies: $124
Cost per dose: $1.35

Preparation

Recipe

Per hive:

  • 1/4 of a SpillTech Maximizer Pad, or 1 Swedish Dishcloth. Cut these in half, and use 2 pads (half doses) per hive.
  • 50 grams glycerin
  • 50 grams Oxalic Acid
The dose per hive is two 25g pads, for a total dose of 50g of Oxalic Acid. 

Prep

Notes
  • Always keep a jug of baking soda solution at hand to neutralize any spills or splashes! (10 heaping tablespoons of baking soda per gallon of water).
  • Best do this in a sheltered outdoor area with no wind, or in your garage. Oxalic Acid is toxic… I strongly recommend not doing this in the kitchen or indoors. If you are outside, be careful about the OA blowing around. It is a similar consistency to granulated sugar, so a gust of wind would tend to blow it around, making for a hazardous workspace and more involved cleanup.
  • Oxalic Acid is poisonous and corrosive. Do not get this in your eyes! Wear eye protection! Be very careful about splashes – apply some of the baking soda immediately to any splashes. 

Procedure

  1. If using the Maximizer Pads, cut them in 1/8’s. For Swedish Dishcloths, cut them in half. You want a pad approx. 3-4″ x 7″.
  2. Prep your storage container – I use a heavy-duty Ziploc bag, and roll back the top so it stays open for easier insertion of the wet pads.
  3. Put on your eye protection, rubber gloves, and mask.
  4. Put about an inch of water in the deeper pan, and bring it to a boil.
  5. Put the shallower pan on the digital scale, set it grams, and zero (tare) it.
  6. Slowly pour in the glycerin to the computed weight (50g x number of treatments).
  7. Re-zero the scale.
  8. Carefully add the Oxalic Acid to the computed weight (50g x number of treatments).
  9. Put the shallow pan in the boiling deep pan. Use the tongs or a spoon to stir the mixture. Stir until the mixture is clear, and all the OA is dissolved. The OA is frequently lumpy… take your time and get all the lumps dissolved, stirring slowly and gently.
  10. Turn off the stove.
  11. Insert the pad material halves, and use the tongs to gently move them around until all of the OA mixture has been absorbed.
  12. Place the OA pads into your storage container, seal, and rinse off the outside and your gloves to remove any residual OA. 
  13. Thoroughly rinse and clean all your equipment outside. If in doubt, pour some of the baking soda solution on it.
 

Usage

Place two pads (2 x 25g of OA) on the top bars of the lower brood chamber. 

Varroa Treatments

Resources

The following videos are highly recommended. Randy Oliver maintains a large apiary in Grass Valley, CA. His climate and conditions are similar to ours, unlike many other videos and resources on the web from beekeepers back east or in Canada. He does good science – he uses controls, data analysis, etc.

Methods

The current EPA approved treatments are listed here.

Calendar of treatment options for typical temperature range

Treatments that are OK to apply with honey supers are highlighted green.

Spring
March  46 – 66 Apivar, Formic Pro, Hopguard, OA Dribble, OA Pads
April  49 – 71 Apivar, Apiguard, Formic Pro, Hopguard, OA Pads
May 52 – 77 Apivar, Apiguard, Hopguard, OA Pads
Summer
June 56 – 83  Apivar, Apiguard, Hopguard, OA Pads
July 58 – 88 Apivar, Apiguard, Hopguard, OA Pads
August 58 – 87 Apivar, Apiguard, Hopguard, OA Pads
Fall
September 56 – 84 Apivar, Apiguard, Hopguard, OA Pads
October 53 – 76 Apivar, Apiguard, Formic Pro, Hopguard, OA Dribble, OA Pads
November 46 – 65 Apivar, Apiguard, Formic Pro, Hopguard, OA Dribble, OA Pads
Winter
December 42 – 58 Apivar, Formic Pro, Hopguard, OA Dribble, OA Pads
January 42 – 59 Apivar, Formic Pro, Hopguard, OA Dribble, OA Pads
February 44 – 62 Apivar, Formic Pro, Hopguard, OA Dribble, OA Pads

Notes

  • Average temperatures are from here.
  • The above table is approximate, based on typical monthly temperatures and conditions. Please check the weather report, especially before using Formic Pro.
  • The Oxalic Acid “OA” Dribble can be used when honey supers are present, but should NOT be used in the supers – it should be applied to the brood boxes only.

 

Tips on Varroa

Varroa is a big challenge for all of us. Do you have any tips or techniques that have worked well for you? Take a moment and share with your fellow beekeepers – please post your comments here.

Other Pests

Yellow Jackets

Yellow Jackets prey on both bees and their honey stores. In spring and summer, they collect insects and carrion to feed to their larvae. The adults don’t eat any of this. Instead, the adults feed on a sugary substance that the larvae excrete after eating the insects and carrion. Later in the year, the adults focus on collecting sugary material, so honey from bees is a prime target. There are several ways to reduce impact to your hive.

  • There are yellow jacket traps available with various attractants, but most find that these have limited value in eliminating yellow jackets.
  • You can make a homemade trap by filling a large bucket with 3-4″ of soapy water. Suspend a chunk of meat one inch above the water. The Yellow Jackets will land in the soapy water and drown.
  • If you can locate the tunnel leading to their nest, you can block the entrance with a rock and dust the rock liberally with Sevin. They will crawl through the Sevin dust and carry the insecticide into their brood chamber. USE YOUR BEE SUIT FOR THIS!
  • You can also try creating a meat trap drizzled with MaxForce FC Magnum roach gel. The Yellow Jackets get the gel on their feet and carry it back to the hive where it kills their queen and larvae. Put this meat bait inside a cage to prevent pets from getting into it. Wet pet food drizzled with MaxForce works well. MaxForce is available on Amazon here.

Skunks

Skunks will scratch at the hive entrance at night and eat any bees that come out to defend the hive. You can reduce this issue by having a hive stand that is 16-18″ tall. The skunks will have to stand on their hind legs to reach the hive, and the hair on their belly is short enough that the bees can sting them. Other parts of the skunk have long hair minimizing the risk of bee stings.

Oxalic Acid Vaporization

We do not recommend OA vaporization.

  • It is very dangerous to breath. You MUST wear a special chemical respirator.
  • It requires many sequential treatments to be effective.
  • It does not penetrate into capped brood, where much of the Varroa is.
  • It should be applied at dawn or dusk when most bees are in the hive.

The [[Oxalic Acid Dribble]] method is much more effective and does not require multiple, sequential applications.

Oxalic Acid Dribble

From BetterBee:
Oxalic Acid Dribble is a method that uses oxalic acid mixed with sugar syrup. It is applied using a large syringe to squirt the mixture onto the bees clustered between the frames.

The bees are not harmed by physical contact with the oxalic acid-laced syrup but, inevitably, they consume a small amount of the oxalic acid containing-syrup which is mildly harmful. For this reason, oxalic acid dribble is best done in a single treatment, not in a repeated series. This is particularly important in winter when individual bees must stay alive for a much longer time. Fortunately, during the brood pause, a single treatment is usually all that’s needed, so an oxalic acid dribble is a satisfactory option at this time of year. The method works best when there are only two boxes on the hive. It can be used when there are more boxes (such as in a hive made up of three or more medium boxes) but that makes for extra work.

Honey Supers: This treatment is most effective in the winter. Do NOT apply to honey supers. Only apply to brood boxes.
Temperature Range: none
Usage
* BetterBee Instructions
* Honey Bee Suite
* Randy Oliver – Oxalic Acid Treatment Table

Hopguard

Hopguard is manufactured by BetaTec. BetaTec research has discovered a natural hop compound that is highly effective in combating Varroa. HopGuard® II and HopGuard 3 are scientifically-proven natural Varroa control systems that provide the beekeeper with a natural, safe, and easy-to-use alternative to traditional harsh chemicals.

Each HopGuard 3 kit contains either 10 or 24 insert strips, ready for use.

Honey Supers: The strong smell may taint your honey.
Temperature Range: daytime temps > 50° F
Usage

  • Overview
  • Instructions
  • The daytime temperature should be above 50°F (10°C).
  • Use 2 strips per brood chamber (i.e. one strip per 5 frames of bees; two strips per 10 frames of bees)
  • Strips should be hung between brood frames.
  • Refer to the package label for full instructions.
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