Tuesday, January 12, 2010

Thymol in syrup for nosema ceranae control

I ran across some studies on the use of Thymol fed to bees in syrup while perusing the web and thought it may of interest to some beekeepers. Thymol is the main active ingredient in Vicks Vapor Rub, to my knowledge.

Apidologie has a publication ahead of print in regards to studies which indicated the feeding of small amounts of Thymol extended the longevity of bees substantially (from 20 days to 24+). The levels of Nosema Ceranae spores were greatly reduced.

I have used thymol in small amounts in my high fructose corn syrup (when feeding was necessary) to prevent bacteria growth and to possibly limit Nosema infection. Randy Oliver has reported on this.

I have done this on a rather large scale, treating 4000 gallons at a time with no apparent negative effects.

Friday, January 8, 2010

new trials with oxalic drip in Florida panhandle

After our fall  treatments for mites, which consisted of thymol cream, formic meat pads, and one "hard" treatment plus lots of feeding of HFCS, we shipped our singles and some doubles to Florida in November. The bees look great. No Fumidil ever in 30 years.
The bees now shipping to Cal. look fabulous too, with very little drop on the bottoms. Much better than most years.

After some research, some email with Randy Oliver, we gave Oxalic treatments a go over the last two weeks in the Florida panhandle. I instructed(I'm still in Michigan for one more day) JJ and the crew to apply oxalic drip to one half of every yard. That's 40 hives out of 80 for every yard. We did some mite rolls 4 days later and are rolling(ether roll) 0 to 2 mites in the hives treated with the dribble of 5 ml per slot applied with a dosing gun we bought from Jeffers. We thinned out syrup with water in a 5 gallon bucket and added 700 grams of acid. Thinner syrup applies easier with a dosing gun.

The untreated side had about 3 to 8 mites per roll. They have been brooding since mid Nov., so they had about 6+ weeks of brooding. JJ reported some brood damage along the top bars, but was of the opinion that it was inconsequential.

My friend Steve Cantu reported that he tried oxalic some years ago and the help improperly mixed the acid in a very high concentration and burned the wings off the bees.

We will follow up and treat the other side of each yard.

Our next treatment will be Formic soaked meat pads.

Last year the mite population got a bit out of hand and it's hard to catch up once splitting and honey making starts.


Mix powdered oxalic acid (available as wood bleach in hardware stores or by the 50 # bag for about $300) with distilled water and sugar (a light syrup)to make solutions at 3.5% strength. We use a small digital scale to weigh the acid.

For small batches mix 140 grams oxalic with 1 gallon of distilled water and enough sugar or fructose to make a light syrup. 140 grams divided by 3785 grams of water (one gallon) = 0.036 or 3.6 % strength. The bees will lick it up.

It will keep for a bit in cooler weather. It's so cheap we just make up new batches.

You can get a doser from Jeffer's supply, but we use a small pump up sprayer and close the tip off until it dribbles. Pick up a small medicine cup from the drug store and practice dribbling off 5 ml. Apply 5ml per seam of bees by running the tip of the sprayer between the frames. Avoid putting much more than 50 ml total per hive.
We have done double deeps  and surpassed that amount with no apparent harm however.

It is reported that treatments done in the fall should be limited to only one or the bees health could be compromised.

success with Thymol treatments for mites

We have dabbled with Thymol treatments over the past 3 years in conjunction with Formic treatments, and lately, oxalic acid dribble. They all seem to work if applied at the right temperatures and intervals. Sometimes I don't get to dig into the hives after the treatments and inspect the bees thoroughly as I would like, as there is so much to do in so little time. We are treating so often with different treatments I often wondered how some beeks do sticking with just one treatment, such as Thymol.

I was just talking to my friend Steve Cantu from Zolfo Springs, Florida and he mentioned that he has *only* used Thymol treatments with a recipe I gave him that another friend (Chris Werner from Indian Summer Honey Farms) gave me. The application consists of Thymol mixed in warmed Crisco with some additional essential oils added, such as Tea Tree, Eucalyptus and blended with powdered sugar with a geared down drill motor and a paddle until a frosting thickness is attained. We generally apply it in the back corners with a hive tool.  He has been successful and has not used any "hard" miticides for about 2 plus years. Steve runs a fair number of hives in Florida, sends quite a few to Cal. for almonds and then pollinates Cukes in Michigan.   

breeding for mite resistance

I was reading the Bee-l and a poster suggested that it would be hard to breed for mite resistance by selecting queen bees to graft from to head up new hives if the beekeeper treated his/her bees to reduce mite populations. The poster thought it would be best to let the bees that had no natural mite resistance die and pick from the survivors. This system is also called "live and let die".

It was my opinion that a beekeeper could keep mite levels reduced (applying natural or chemical miticides to remove mites from the bees) to maximize a monetary return on the investment and labor and still pick the best hives for larvae to raise new queens.

keeping bees healthy

Some of you may be interested in the problems beekeepers face to keep the bees healthy from Asian mites.

Beekeepers are very challenged to keep the bees healthy from the ravages of Varroa mites and the corresponding viral infections from mite punctures. It is very probable that CCD is partly caused by virus infections and may be a yet undiscovered virus.

At our honey farm, Sleeping Bear Farms, we are making inroads to controlling parasitic mites with organic plant extracts and weak acids that kill or weaken mites, but do not harm the honeybees significantly.

Lately we have treated with oxalic acid in a water solution at 3.5 % and dribble 5 ml between the combs right on the bees. We have found some minor brood damage, but very little. The mites were substantially reduced upon inspection after 4 days.

We have also used Thymol oil processed from Thyme plants placed on top of the combs in a mix of sugar, like a cake frosting. This had also worked well.

Also in our program is formic acid that we soak on meat pads in a 65% solution at 35 grams per meat pad. The pads have a light plastic coating which slows the release of gaseous formic acid which kills mites.