Varroasis Infested Brood!

We have observed the use of various essential oils has a positive effect on the bees. The underlying mechanisms of action are not fully understood; therefore claims of efficacy cannot be made. There are also various reports that state they actively stimulate the immune system in helping to resist pathogens. This is also poorly understood. Also, the process in which the oils are extracted and growing conditions can make a difference in efficacy from year to year making it even more difficult to make claims.

We present no claims of efficacy using essential oils only observations.

The four pictures of the comb below were taken late October from control hives that were let go too long without treatment. They had more than 50% infestation in the cells and were treated with Apistan and wintergreen grease patties in early October. After three weeks we found several live deformed bees walking around on the comb and many more dead deformed bees in the cells. Even though the Apistan killed about 90% of the mites, by this time the residue (excreta) left behind by the mites in the cells caused the PMS (Varroasis) to persist, killing many of the bees in the cells before they hatched. We opened capped cells and found dead deformed bees with no apparent sign of any mites. The viruses and bacteria carried by the mites seem to keep a hive infected for several weeks after the mites are gone. A few years ago we took some frames from a hive that died of PMS in late summer. We put these frames into an uninfected hive and after three weeks (one brood cycle) found signs of PMS in the combs of these frames with no signs of mites. The following spring we made splits with PMS infected comb that died the previous fall, and after one brood cycle we found no signs of PMS - only healthy hatches. There needs to be a study on the time factor on how long these bacteria and viruses stay viable in brood comb.

Treatment for mites needs to be administered early enough for the bees to hatch at least two healthy brood cycles to insure the health of the colony for the winter months.

 

The comb to the right shows dead bees in the cells that did not hatch. The comb below shows a mite on a pupa.

 

 

 

 

 

 

 

The combs to the right and below show deformed bees and the dark greasy looking comb from mite infestation and disease.

 

 

 

The comb below was fed essential oils during late winter, late summer and early fall of 1999 which kept the hive healthy. Our feeding results were much better this year as compared to last due to this summer's drought with long periods of nectar dearth. We are currently working on a new feeding system we hope will work as well during a honey flow as the feedings do during dearths of nectar.

(Mid October Photo)

Hives fed essential oils along with Apistan strips make a rapid comeback. In some of our earlier experiments we found hives in collapse with PMS and heavy mite infestation. We then fed these hives wintergreen syrup along with Apistan. After 24 days of treatment Dr. Amrine, Harry Mallow and I opened several hundred cells in these hives and found no mites with all visible signs of PMS gone. The synergistic effect of the two worked real well in bringing these hives back from near collapse in a short time. But with mites now showing resistance to fluvalinate this combination system will probably not work as well.

We believe from our observations the oils fed during dearths show an improvement in the colonies overall general health. The oils seem to have a positive effect to the bees and the combs with no apparent harmful affect to the bees or young larva. We also noticed a few weeks after our organic acid tests the combs seemed clean with nice light colored cappings as when fed the oils. The fumes from the acids also penetrate the cocoons as do the larval food with the oils.

We believe organic acids and essential oils being found naturally in honey may be one of the reasons why bees are showing resistance to mites in different parts of the world during certain times of the year. What blood is to the human body, essential oils are to plants. They are the oxygenating and regenerating immune defense system of plants.

The Black Walnut Question?

I asked a friend of mine, Calvin Dolan, a timberman from Oldtown, Maryland, if he had cut or seen any bee trees lately. He told me he would not cut bee trees and used to see several a year, but had only seen two in the past two years and both were in "Black Walnut Trees" (Juglandaceae Juglans Nigra)

The State of West Virginia has recently made a survey on feral bee colonies and the only surviving colonies were found in Black Walnut trees. There have also been reports of surviving feral colonies in Pennsylvania.

Bob Noel

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