# Varroa treatment threshold



## cg3 (Jan 16, 2011)

Coming out of my first winter I have 3 hives Wall-to-wall bees (2 Langs, 1 TBH) Dandelions just starting here. Used Apigard last fall on the Langs. Just did my first sticky board count. What's this about count only the red mites (I'm colorblind)? In 72 hrs TBH and one Lang dropped 6-8 mites. One Lang dropped approx. 40. Seems high. Should I treat? With what? Hoping to requeen later this year with resistant stock.


----------



## AmericasBeekeeper (Jan 24, 2010)

40 is nothing to treat for!


----------



## honeyshack (Jan 6, 2008)

40 at this time of year is high. 18 per day is a 3% infestation.
At one percent at this time of year you will see a drop in honey production in the summer
At 4% damage to bees via DWV and other illness will show up.

1% at this time of year is really the limit. However that number will drop if you have other stressors like nosema, Virus pressure, nutrition pressure and weather pressure


----------



## cg3 (Jan 16, 2011)

Would MAQS be appropriate this time of year. Highs 60s-70s, lows 30s-40s.


----------



## FindlayBee (Aug 2, 2009)

You can use the MAQS when the daytime temperatures are between 50 and 92 deg F.

www.miteaway.com


----------



## indypartridge (Nov 18, 2004)

cg3 said:


> One Lang dropped approx. 40. Seems high.


50 (in a 24-hr drop) is the threshold I usually go by, but as honeyshack noted, at this time of year, 40 is high.



> Should I treat? With what?


I've used powdered sugar in the past. I might consider MAQS if the powdered sugar wasn't knocking down the mite counts to my satisfaction (or if time was an issue, and I didn't want to do repeated sugar treatments).


----------



## AmericasBeekeeper (Jan 24, 2010)

Most references to Varroa monitoring and controll list Drs. Delaplane and Ellis research which says - 
"Many studies have been conducted in an effort to determine the economic threshold for varroa in a colony but results have varied. Factors affecting the economic threshold include temperature, colony strength, geographic location, the presence of other pests/pathogens, level of colony resistance to varroa, etc. As such, an economic threshold for varroa probably will not be universal and will have to be determined regionally. In the U.S., independent studies have suggested that the economic threshold for varroa mites is around 3000 mites/colony colony (Delaplane and Hood 1997). Again, this number will vary depending on a number of factors, including those listed above. With the establishment of economic thresholds and sampling devices, varroa mite management has become easier, although IPM is not as widely-practiced by beekeepers as one would hope." 
http://entnemdept.ufl.edu/creatures/misc/bees/varroa_mite.htm
Burgett, D.M., Kranz, G.W., and Capizzi, J. 1987. An effective field detection method for Varroa jacobsoni, the Asian honey bee brood mite. Oregon State University Pest Information Leaflet 46, reprinted in The Speedy Bee 16: 2.
Ball, B., and Allen, M.F. 1988. The prevalence of pathogens in honey bee (Apis mellifera) colonies infested with the parasitic mite Varroa jacobsoni. Annals of Applied Biology 113: 237-244.
Central Science Laboratory (CSL). 1996. Managing varroa. Advisory leaflet PB 2581, Ministry of Agriculture, Fisheries and Food, London, United Kingdom.
Delaplane, K.S., and Hood, W.M. 1997. Effects of delayed acaricide treatment in honey bee colonies parasitized by Varroa jacobsoni and a late-season treatment threshold for the southeastern USA. Journal of Apicultural Research 36: 125-132.
Devlin, S.M. 1998. Comparative analysis of sampling methods for varroa mites (Varroa destmcîor Anderson and Trueman) on honey bees (Apis meiliferra L.), http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ61548.pdf (Accessed September 12, 2006).
Ellis, M.D. 2000. Using Powdered Sugar to Detect Varroa. Jan. 2000. http://entomology.unl.edu/beekpg/tidings/btid2000/btdjan00.htm#Article2 (Accessed September 12, 2006).
Macedo, P.A. and Ellis, M.D. 2001. Using the Sugar Roll Technique to Detect Varroa Mites in Honey Bee Colonies, http://ianrpubs.unl.edu/insects/g1430.htm (Accessed September 12, 2006).
Martin S.J. 1999. The Virus, Mite And Model: A Useful Approach Towards Varroa Control. Proceedings of Apimondia Congress XXXVI: 141-142.
Ritter, W., Leclercq, E., and Koch, W. 1984. Observations des populations d’abeilles et de varroa dans les colonies à dif férents niveaux d’infestation. Apidologie 15: 389-400.


----------



## cg3 (Jan 16, 2011)

In other words "Don't panic."? My goal this year is to increase as much as practical. Just want to keep their numbers up enough to support a couple of splits. Am currently investigating local sources of resistant queens. Don't want to do anything yet until I see how swarm season goes. I guess now my plan is to monitor more closely and split from the colonies with lower numbers. Reasonable?


----------



## beedeetee (Nov 27, 2004)

My threshold is 40/day on August 15th. Last year I didn't have any that dropped that many, so I didn't treat any (all of my hives made it). 40/day at this time of year seems like a lot. They will be dropping hundreds a day by August.


----------



## Ted Kretschmann (Feb 2, 2011)

You have to do an ether or alcohol roll. This involves about 300 bees. So the mites that are recovered can be used to determine how may mites per hundred bees?? One or two mites per hundred is not enough to worry about. TK


----------



## jdpro5010 (Mar 22, 2007)

I agree with Ted. Do a alcohol wash or ether roll. 1 cup equals approx. 300 bees.


----------



## indypartridge (Nov 18, 2004)

Instead of alcohol or ether, you can also do a sugar roll (and not kill bees!). 

Here's how (Thanks, Marla Spivak):
http://www.extension.umn.edu/honeybees/components/pdfs/posters/varroamites_155.pdf


----------



## WI-beek (Jul 14, 2009)

We in the USA have a much higher mite load tolerance than in the UK. They call for treatment at much higher number. If you have a drop of 40 a day I would be treating no. In a month you will have a way to many mites.


----------



## cg3 (Jan 16, 2011)

To be clearer, it was 40 in 72 hrs (13+/day) but I think I'll try another count method before I treat. Cup of bees=300. How exactly do I collect a cup of bees?


----------



## WI-beek (Jul 14, 2009)

Whoops! I meant I would be treating now and UK calls for treatment at a much lower level. 

Here is a varroa count calculator from uk
https://secure.fera.defra.gov.uk/beebase/public/BeeDiseases/varroaCalculator.cfm

According to this you should treat in a month. do you want to do it now or when honey supers are on?


----------



## honeyshack (Jan 6, 2008)

To do the wash, you need the bees as stated, add the rubbing alcohol or winshield washer fluid (good to -30) and then shake hard and continuous for 8 minutes or let stand for 30 min -2 hours or more. The longer the more mites which fall.
Strain and do the counts and the math


----------



## loggermike (Jul 23, 2000)

>>How exactly do I collect a cup of bees? 

Heres how I do it. Take out a frame of brood and look it over very carefully so you are positive the queen is not on it. Put the frame inside a 5 gallon plastic pail and give it a shake. It will then be easy to scoop up a cup of bees and return the rest to the hive. I use a plastic measuring cup that is screwed to the end of a frame top bar for a handle.


----------



## Pete0 (Mar 30, 2002)

Another way is to again take the frame of brood with nurse bees and without the queen, shake it onto a telescoping cover setup like a catch basin, pick the cover up by a corner and rap the opposite corner on the ground moving all the bees to that corner, pour the bees into your jar and screw on the lid. Mark the jar for one cup with tape or magic marker. Works well for me.

Good luck!

Pete0
Bena, VA


----------



## jdpro5010 (Mar 22, 2007)

I don't believe the sugar roll is as accurrate as an alcohol wash or ether roll. All of the above ways for an alcohol wash will work well but the main thing is to do the exact same thing everytime you do the test. For example shake them for the same amount of time every time, choose a similiar looking frame (brood wise) every time. Any small differences could, in theory, alter your results.


----------



## Axtmann (Dec 29, 2002)

IMO it is unfair to tell a young beekeeper 13 mites per day is not a problem, or don’t panic.

A naturally mite drop of 13+ mites per day, this time of the year needs a mite treatment immediately, more than 95% of the mites breeding in cells and not sitting outside on bees.
This colony might have thousand mites or more and there population doubles every 21 days. 
For example: today 1000 mites, in 21 days 2000 + mites, in 42 days 4000 + mites, in 63 days for sure more than 9000 mites, a week or two later there no mite in the hive. The colony is gone and lots of mites in the neighbors hives. 

As soon as I have more than 5 mites per day I treat, I give them a strip with thymol and had never a problem. This is the easiest way for me to keep my bees healthy. You also can use formic. Our bee institute in Kirchhain – Germany made a thymol test in comparison to formic acid on almost 50 colonies. At the end, formic reached almost the same result, but needed 4 treatments during 2 weeks, compare to one thymol treatment.


----------



## jim lyon (Feb 19, 2006)

Very informative post Axtmann. I have been using Thymol for a number of years with good success. Used to use Formic but switched over because of the nasty nature of Formic and hated to see rusting of anything metal in the hives. What is your experience with which one is more effective at lower temps and safer at high temps?


----------



## Axtmann (Dec 29, 2002)

Jim Lyon

As I said, with 4 formic treatments within 2 weeks, you can come close to the result with the thymol treatment. For lower temperatures or up and down temperatures (warm and cooler weather) thymol is much better. With temperatures over 30°C (90F ??) my bees had no problems with thymol.

Formic evaporate faster and the treatment time is shorter, dropping temperatures during FA treatment means formic is gone without the result it should bring. Using thymol as a crystal form, with lower temperatures the evaporation slows down and starts again with raising temp (my experiences). There is still enough thymol to fill the hive with fumes again. 

It’s easy to find out, put the strip in a freezer – evaporation stops totally, take it out and it starts again. Using Thymol in paste or in a sponge …don’t frees it, the cold separates the different ingredient and you destroy the product. 
They also tested the expensive formic strip here and the best thing on it is (IMO) the advertising, I’m not using it.


----------



## WI-beek (Jul 14, 2009)

axtmann

do you have any recipe for tymol you can share and how to apply it?


----------

