The Beekeeper’s Companion Since 1861
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The Classroom

The Classroom March 2015

- March 1, 2015 - Jerry Hayes - (excerpt)

Q Fungicides in Bee Hive Paint

I have a suspicion that fungicides that are used in paints are contributing to CCD. What are your thoughts?

Harold in Missouri


Thank you for the interesting question about fungicides in exterior paint and possible contribution to CCD. It sparked a curiosity and opinion if you don’t mind. Here is a statement from a paint industry web site, “Exterior paints: All exterior paints have fungicides, and low-biocide paints are not available for exteriors. The best choice for an exterior paint is one that has zinc oxide as the fungicide. Next best choices are zero- to very low-VOC (volatile organic compounds) paints, acrylic or latex paints, and recycled water-based paint. Avoid oil-based paints because of their high VOC content, as well as paint from old cans that may contain mercury or lead.”

Certainly any additional exposure to toxins by honey bees is the goal. Since honey bees forage in a 2-2.5 mile radius of their colony, there are lots of natural plant toxins that honey bees have encountered for millennia and now manmade toxins, not even counting the ones we as beekeepers premeditatedly put in a colony. Honey bees are tough but not impervious to all of these when they are added together.

According to the statement above, all exterior paints have fungicides and biocides in them to make the paint perform as expected in this harsh outdoor environment. I am not sure what this means if we only paint the exterior of the hive to make the expensive woodenware last longer. Colonies have been painted with oil based and older paint formulations for decades way before CCD was termed. Beekeepers have used linseed oil and tung oil and other oils to keep woodenware from rotting. Zinc- and copper-based wood treatments are also used. My biggest concern is the solvents used to keep these materials in suspension and allow them to penetrate the wood to keep fungus and termites from having a buffet. The solvents, VOC’s, are the most potentially damaging to the colony if not allowed to evaporate and air dry before using them for a honey bee hive. You and I don’t like the odor or the breathing this stuff; that is why we do it outside when we apply it.

Honey Bees are great users of ‘propolis’ to coat the inside of the colony structure, hive body, frames bottom board, top etc., and form an envelope, a cocoon if you will, as part of the colony’s immune system to protect them from toxins and pathogens. This envelope on the inside and a well-aged outside wood paint or wood preservative coating applied by the beekeeper will give the longest life to the colony and the hive.

Q Moldy Syrup

Jerry, I make my own bee feed from beet sugar with a 2 to1 ratio: 2 parts sugar and 1 part water.  After a while I do see some black mold growing on the sides of the feeder bucket. I have heard you can add bleach or vinegar to the bee feed and this will slow the mold down as well as the fermenting. I was wondering if this was safe for the bees and if so, how much should be added per gallon? Or is there something else that could be added to the feed to help prevent this?



This is a perennial problem and it just happens in this competitive biological soup we live in. It is basically just this tremendous nutrient source that allows fungus, yeast, bacteria, slime mold and all sorts of other things to use this sugar solution to grow and reproduce. Nothing is sterile in the sugar itself or the water used to mix it or the feeder you put it in and then all the stuff floating around in the air. This is a high school science experiment–no different than you leaving a glass of fruit juice out in a warm environment for several days. Would you drink it?

Chlorine is added to municipal drinking water sources to keep ‘organisms’ from being able to exist in public water supplies. Then, we drink it. Many times a teaspoon of household bleach is added per gallon on sugar syrup to retard the growth of some molds, fungus and other organisms in sugar syrup.

So, the question is what does this do to the gut bacteria in honey bees and does it have health effects? The potential detrimental effect is probably less than a feeder full of mold/fungus. Take care Steve.

Q Vertical Integration

I work for a nonprofit group; we do bee rescues of wild, feral honey bees that infest homes and swarm where they are a nuisance. We relocate these bees to Coop farms (farmers donate land, we get them an agricultural exemption, then we subsequently tend to the bees and ensure their survival).

So, here is my thought: I think our nonprofit services can offer almond growers a huge financial incentive to keep bees permanently. Instead of them having to purchase and maintain hives, we can just place them into our Coop program. We take them commercial bees, or bees from our rescues, and we tend to them. That saves them the upfront money and having to pay a beekeeper. We would just ask them for a (large) donation to our nonprofit’s services. What are your thoughts?

Cameron Barnette


And that is exactly what some large almond growers are experimenting doing. They have purchased a percentage of a commercial beekeeper’s operation and they get the bees for pollination. But, in turn, they have to burden some of the risk and cost during the other 330 days of the year that the commercial beekeeper normally must burden by himself. The beekeeper then becomes at some level a contract employee. It is all a work in progress to see if there is a ‘business model’ that can be developed to be successful.

Q Varroa Mite Cycle

Jerry, I am trying to understand how a bee brood break helps control Varroa?  This is what I know:

– 1.1 varroa survive when the bee emerges on average
– varroa build up curve lags bee build up curve by approximately three months
– varroa can survive six months in the phoretic stage when there is no bee brood
– varroa, when bee brood is present, are in the phoretic stage 4.5-11 days.
– varroa usually survive less than 5 1/2 days away from bees

In South Carolina I am interested in splitting first of March, then first of June after the spring nectar flow ( three months later), then first of August (approximately 2 months later) after cotton, and let the final split build up on soybeans.  I know a lot of colonies succumb after the honey supers are pulled the first of June due to varroa.
I typically marry another queen with the split w/o a queen.  Hence, it probably takes 5-10 days for the new queen in the split to hit full speed with her egg laying.  I assume the split with the old queen keeps right on laying.  Approximately, 1/2 the brood ends up in each split.  So, there is probably a brood break of 5-10 days at most. I assume 1/2 of the varroa from the original colony end up in each split. I also assume most of the field bees end up with the split still on the original location. However, most of the varroa are in the brood.
What am I missing and how does this all fit together to control varroa with a brood break?

Dave M. in South Carolina


Well if I understood the question correctly, it all has to do with Varroa being a parasite that requires honey bee brood, larvae and pupae to reproduce on. If brood is not available, then the mated female Varroa, the foundress mite, is then exposed /phoretic waiting, if you will, on adult honey bees until they get a pheromone signal from brood. This is what these mated foundress Varroa mites need as an obligate parasite to enter and begin the reproductive cycle on to maintain their species. If you can create a broodless condition, then it is a great time to use some form of Varroa control as they are all out in the open. None are behind capped cells safe and protected while they produce another generation.

Or, if you can create a situation with only a few Varroa in a split and if there is drawn comb, the queen can lay many more eggs a day than there are Varroa. The bees take advantage of this reproductive surge and for a while they can out reproduce the mites. But, if in your splits there is a large amount of sealed brood containing reproducing Varroa, then there is little advantage. Varroa need developing honey bee larvae and pupae to reproduce on. Limit this and a colony can temporarily out-reproduce Varroa. Do not limit this and there is little or no advantage because there has been no lack of larvae or pupae for the Varroa to use to maintain the species and they haven’t missed a reproductive beat.

A complete brood break allows either treatment, or the ability of a colony to then out reproduce Varroa if weather, and resources are optimum.

It is the opposite situation for a full size colony when fall begins and the honey bee colony is preparing for winter. The bee population drops, the queen slows laying and the problem begins as the Varroa population does not drop, so the proportion of Varroa mites to honey bees increases. If Varroa control hasn’t taken place in late summer, early fall then direct and indirect negative health events are caused by Varroa.

Q Feeding Brewers Yeast

I have a fast question for you. I am in the process of making no-cook candy boards for my colonies. Will mixing in brewer’s yeast be a problem? The recipe calls for 10 lbs. sugar, 3 tbsp. of lemon juice and 2 cups of water. Mix it and let it harden. I have a 1 lb. package of brewer’s yeast.



Remember that Brewer’s yeast or anything fed to bees when confined because of cold weather or changeable weather patterns means they can’t get out and defecate to get rid of the indigestible roughage.  If the bees have to hold on to indigestible material in their intestines, then this is a great environment for other organisms like Nosema to grow and prosper. Brewer’s yeast is a nice addition, but doesn’t …