Brushy Mountain's Question of the Month: August

Question of the Month: Mites

Summer is drawing to an end and fall will soon be coloring the trees. Beekeepers are taking off their last supers of honey and preparing their hives for winter. Every year we harp on the importance of treating for Varroa Mites but when is the correct time to treat? 

It is best to know your mite count before you begin treating. Mites have been able to develop a resistance to some of the products on the market. If you know your mite count before and after you have treated, you can determine if you were successful. Here are two options to obtain a correct mite count:

• Corex Sheet. This is a sheet which slides under a screened bottom board. Spray the corex sheet with cooking oil and as the mites fall from the hive, the mites will stick to the sheet and can be counted easily. Remove sheet after 3 days to get a total count of mites. Divide total by 3 to get the average mite drop in a 24 hour period.


• Sugar Shake. Place a few tablespoons of powdered sugar in a mason jar, add ¼ cup of bees and gently "slosh" the bees around ensuring they are fully coated. Replace the lid with #8 hardware cloth and shake the bees down over a white sheet of paper. The sugar will dislodge the mites allowing them to fall through the screen. This will give you an average mite count for your hive.

Below is a very general guide to determine if the colony should be treated.

Sampling Method	Spring	Fall
Corex Sheet	5-10 mites	50-60 mites
Sugar Shake	3-4 mites	10-12 mites

This is the time of year to begin treating for varroa mites if your count falls above or near the general guide. Treatment in early fall is vital for a healthy winter colony. The virus that persists after the mites have been treated is what poses the real threat for winter loss. It takes a few generations of brood rearing for virus levels to reduce. If you wait until late fall to reduce the Varroa population, due to the viruses, you will still have unhealthy bees going into winter. The best time to deal with the mites is late August/early September depending on your location. 

Top Treatments for Varroa Mite:

• 1. Soft Chemicals: An effective treatment while leaving the least amount of residue. We offer Api Life Var and MiteAway Quick Strips. Both are 95% effective, however, both work through the evaporation of essential oils or organic acids, thus making themweather sensitive.


• 2. Hard Chemicals: Will kill the Varroa Mites but label instructions must be followed and do not leave on longer than recommended. We supply Apistan Strips, Check Mite Plus and a newer treatment, Apivar. Keep in mind varroa have shown a resistence to Apistan and Check Mite upon continuous use.


• 3. Non-Chemical: Beekeepers have been using powdered sugar to monitor mites but if heavily dusted with a Dustructor, it can control the mite population. The Varroa reproduction is directly tied to the bee reproduction cycle. Because drones are capped longer as brood, the Varroa are more attracted to drone brood where they can lay more eggs. Using Drone Foundation or a Drone Frame, you can wait until the brood is capped, remove and destroy the foundation. Non-chemical or IPM techniques can be effective to control mites; however, they require dedication and time to be successful.

Brushy Mountain's Question of the Month March...

I treated my hive for Varroa Mites in the fall, do I need to do the same in the spring?

The Varroa Mite population directly ties to bee production. As the queen begins to lay heavily, trying to reach maximum population before the nectar flow, the Varroa mite population will also rise.

• Female mite enters a cell of maturing bee before it is capped
• She waits 60 hours before laying eggs (lays an additional egg every 30 hours)
• First egg will be male and subsequent eggs will be female
• Mites will feed on the pupating bee (this can infect bee with viruses)
• Female mites will exit with adult bee

Every hive needs a thorough inspection to ensure that the mite population is not overwhelming, diseases are not found, and there is a strong population of bees in your colony. With continuous production of brood, the mite population will grow faster and be larger.
The Varroa Mite creates open wounds on the bee, leaving the bee more prone to infection, as well as vector (transferring) viruses, which compromise the health of the bees and the entire colony. 
There are several ways to check for mites within your colony:

Sugar Shake. Place a few table spoons of powdered sugar in a mason jar (replace the lid with #8 hardware cloth) along with roughly ½ cup of bees (around 300 bees) and gently "slosh" them around, ensuring they are fully coated. The sugar will dislodge the mites,allowing them to fall through the hardware cloth onto a clean surface. Count the mites that are dislodged from the bees; if the mite count exceeds 3, treatment is recommended.

Corex Sheet. This is a sheet which slides under a screened bottom board. Spray the corex sheet with a cooking oil so when the mites fall from the hive they stick to the sheet and can then be counted. Insert the sheet for 3 days and then remove it to count the mites. Once you have a total, divide it by 3 to get the average mite drop in a 24 hour period ; if the mite count exceeds 10, treatment is recommended.

If this is your first year in beekeeping or you just purchased a NUC or a Package, and you received your bees from a reliable source, they would have already been treated for mites prior to your pickup, but may still have mites; however, these colonies should not need treatment until late summer/early fall. 


Treatments

Integrated Pest Management (IPM) methods work with the behavior and biology of the target pest to aid in its control. Several methods that can control the mite population include:

• A screened bottom board which allow the mites to fall out of the hive
• Drone trapping/Varroa trapping using a Drone frame or Drone foundation
  Remove frame after cells have been capped and freeze for 48 hours. Reinstall frames after thawing.

IPM methods often are not a sufficient form of control and more traditional methods need to be used. We, and many in the scientific community, strongly encourage the use of “soft chemicals”. These are naturally occurring products and many naturally existing in honey. The two most common are:

Api Life VAR. Api Life VAR is made with thymol, which is used in mouthwash, and other essential oils. Evaporative wafers are placed on the hive and the thymol vapor kills the varroa.
MiteAway Quick Strips. MiteAway Quick Strips use food grade formic acid, which naturally occurs in honey.
Other treatments, such as Apistan and Check Mite Plus, are on the market but resistance has been documented; therefore, further monitoring is necessary. A newer treatment, Apivar, is labeled to kill 99% of mites with a single treatment.

Monitor your mite count and if infestation is high, treat as needed. 

ORIGINAL SOURCE: BRUSHY MOUNTAIN