Would you just treat your hive with just sugar dusting?

[mathew]

I've never treated my hives for varroa mites with formic acid before. I've been apprehensive as I've heard that Formic A stresses the queen and now most queen breeders do not have supply of queens at this time if I sustain queen problems over the winter. The only treatment i've used so far is sugar dusting. I've been dusting once a week with 2 cups of sugar per hive.

My highest mite count for one hive out of 300 bees is 21 which is really high.

[Kathyp]

there have been some studies done that show powdered sugar dusting is not an effective treatment for mites.  some people swear by it and that's all they use.  the only way to evaluate it for yourself is to watch the health of your hive.  all hives have some mites so nothing you do will get rid of them all. 

if you are worried about using something toxic in the hive then i recommend Apiguard, but it has it's drawbacks.  it takes 4 weeks to treat and you need warmish temps.  for us northerners, that makes it hard to use in the late summer or fall.

you might consider going treatment free.  it will mean some higher losses in the beginning, but it saves money and time in the long run.  i will tell you that i was not able to do it with purchased bees.  i had to dig mine out of walls and catch swarms :-)  something to consider for the future.

we have one advantage up here.  we usually have a complete brood break over part of the winter.  that means that we don't start the spring build-up with a heavy mite load. 

[mathew]

Kathy thats valuable advise for our northern region. I'm sure you remembered that this year's winter was really mild. I remembered treating mites with Oxalic acid in december and I was surprised to see that there was some capped brood on one or 2 frames but very minimal. The capped brood was about the size of a circle your thumb and pointer finger can create. That brood break I had was most likely for about 3-4 weeks starting in January to early February. I know my queen was already laying when the Purple Crocus was blooming and the hazelnut catkins were hanging,

I want to be able to be treatment free but I only have 2 hives and a nuc. If i grow my hives to 4 next year, I would use a hive as a test and see how they can get by.

So you did not try treatment free on ur purchased bees? My 2 hives were started as nucs last year July.

[FRAMEshift]

there have been some studies done that show powdered sugar dusting is not an effective treatment for mites. 

Kathyp, do you remember where you saw these studies.  I haven't read that and I would like to track it down.

[Kathyp]

was just reading one.  will have to try to remember where i saw the full thing.  came out in 09 i think.  you might be able to google it before i get back here. 

[Kathyp]

http://www.countryrubes.com/images/BCA_Nov_2009_powder_sugar.pdf

think this is it.

and then there was this on BM

http://forum.beemaster.com/index.php?topic=25218.0

probably more if you look around a bit.

[FRAMEshift]

Thanks kp.  :-D  It's interesting that the BCA article also presents evidence from other studies showing that more intensive and frequent treatments do work, at least over the short run.  And none of the researchers looked at treating with PS during a break in the brood cycle, when all the mites are exposed and vulnerable.

[BjornBee]

Great advice Kathy.

I'm no fan of the acid treatments. But if one was to use the acids, then I think it's best to use them prior to the fall flow, and without the queen being in the hive. That way the fall raised bees will not be "aged", and the mites are knocked down prior to doing their damage.

Not that knocking down mites is a bad thing anytime you do it, but knocking them down after they affected the fall brood cycle is a bit like throwing your money away after the fact.

Fall treatments should of been done weeks ago for best results and the best chance of hive survival.

[FRAMEshift]

Could someone explain exactly when and why the risk peaks in the fall.  We haven't had much of a mite problem yet so I have no experience with this.  I have read in various places that most mite damage is in the summer, or in the spring.  And now Bjorn suggests the fall.  So I don't understand why one season would be more risky than another or which season is the worst.

[caticind]

http://www.countryrubes.com/images/BCA_Nov_2009_powder_sugar.pdf

think this is it.

Thanks for that link, Kathy!  To summarize for everyone too busy to click - dusting with sugar using the method described was found to remove at least 35% of phoretic mites.  In their study it does not seem to reduce mite counts compared to untreated controls.

However, one of the authors of the study said, in a letter discussing the study, "...Research shows it doesn't work long term. But, in real world situations it does. What to do? I'd
treat with PS until research catches up with reality."

[Kathyp]

So you did not try treatment free on ur purchased bees?

i did and i lost them....but i might have lost them anyway.  bees die sometimes :-)  
i also lose a % of the swarms i catch each year, in part because they have come out of the pollination hives in the berry fields.  they will often only last a year and then they are done.  sometimes they surprise me and i get a great hive, but the ones i really want are the ones that are in walls, swarm from trees, etc.

[caticind]

Could someone explain exactly when and why the risk peaks in the fall.  We haven't had much of a mite problem yet so I have no experience with this.  I have read in various places that most mite damage is in the summer, or in the spring.  And now Bjorn suggests the fall.  So I don't understand why one season would be more risky than another or which season is the worst.

rdy-b posted this in another recent thread on mites:

http://www.scientificbeekeeping.com/index.php?option=com_content&task=view&id=23&Itemid=40

[AllenF]

There are a lot of charts out there showing this, but as the bees start to make brood in the spring, they are making mites also.  Start out with 10 mites.   Then the next week they make 50 mites.   Then they make 250 mites.  Then they make 1000 mites.  Each time they reproduce, they have more breeders to work with and this compounds.   By the fall, they make 5000 mites after several brood cycles.  10 to 5000 are just numbers to work with. 


 

[BjornBee]

Could someone explain exactly when and why the risk peaks in the fall.  We haven't had much of a mite problem yet so I have no experience with this.  I have read in various places that most mite damage is in the summer, or in the spring.  And now Bjorn suggests the fall.  So I don't understand why one season would be more risky than another or which season is the worst.

I think the chart is on target. Bees don't come out of winter with 50,000 bees. They come out with a smaller number and build up through spring, outpacing the mites when you look at the mite per bee ratio. Then as the bees slow down over summer, and some bees stop for a period of time, and the lagging mite explosion is seen as a much higher mite to bee ratio starting in Mid-August and grows RAPIDLY through mid-October when the bee brood cycle stops.

That is why treating in mid-August PRIOR to the mite exposion and high mite to bee ratio, allows much more damage to happen, compared to earlier in the year.

There are many side smaller issues and impacts that play into this scenario. Many drones are infested in the spring and summer and simply die off, etc. But later brood cycles, have no or very little drone production, allowing much more damage to be placed upon workers.

So many factors play into it. But the key is to start the fall brood cycle with as little mites as possible. And waiting till after the mites do their damage to the fall brood cycle is something to guard against. Whether that is through treatments, management, or other IPM, it does not matter. Knowing what will happen in the 60 day fall brood cycle is very important.

[FRAMEshift]

That is why treating in mid-August PRIOR to the mite exposion and high mite to bee ratio, allows much more damage to happen, compared to earlier in the year.

Just to be clear, when you say damage, do you mean damage to the bees by the mites.... or damage to the mites from the powdered sugar?  Are you saying that treatment in mid August is better than treatment in mid July?

I ask this because we have been experimenting with breaking the brood cycle by doing a late June split and treating the broodless hive with PS up till the middle of July when the new queen starts to lay.  What do you think of that idea?

[BjornBee]

Frameshift,

I think my comments were more for that beekeeper with the "one treatment" approach. If you sugar shake in June and July, I think that would work fine. Any ongoing IPM is probably better than letting the mites build up like most beekeeper do, then treating them after the bees have been exposed for long periods of mite pressure.

After I take honey off....if I take honey off  :roll: , I do my winter splits usually in July, since most of my nuc and a good number of queen orders filled. I requeen and most hives go through a broodless period like you are doing. So I think that, along with any additional IPM such as drone brood, sugar dusting (I'm not really sold on that myself) or anything else, is best done after honey is taken, in conjunction with any dearth and bee slowdown, and the beginning of the fall brood cycle.

Yes, I am speaking of damage to the bees by the mites. Damage can take many forms such as a decrease of brood production from too many cells being cleaned out, shortened lifespan from mite disease transfer and immune system breakdown, to even a lack of proper diet from overworked bees having to deal with high mite loads.

[mathew]

Bjorn,

You have given me lots of insights on mite population increase. I sugar dust once a month from April to July. From Mid-August onwards I've been sugar dusting once a week. You mentioned about 60 day fall brood cycle. Do you have an article online that explains this? how is the fall brood cycle different from the brood cycle in June and July?

KathyP,

Have you sugar dusted the bees during the break in brood cycle? I am wondering coz at this time it is usually when the weather is really cold and it is not recommended to open up the hive.

[BjornBee]

Thank you Mathew,

I never keep stuff bookmarked etc.

I took part in mite shakes for thousands of beekeepers over a three year period. The mite counts almost always had numbers close to this....

April - 1
May - 3
June - 5
July - 8
August - 11
September - 25
October - 40+

These would be averages over many hives tested. I may be off on the numbers but the pattern is what you should see. The bees April through July, had usually mite counts below the threshhold of 10 mites per 1/2 cup bees, which is something like 225 bees if I remember. We knew that from the 15 of August to the 15 of October, the mite counts would explode, even if they just really kept doubling. many times, the numbers would multiply by 4 or 5 times during this period. Shaking out 100 mites on a simple sugar shake was often seen.

But if you could knock that mite count of between 5 and 15 which was real normal going into August, down to 2 or 3, then that same multiple factor would still keep the mites at manageable levels...many times without the need to fall treat.

The 60 days fall brood cycle or period you should strive for, is indicative for the northern climate above the mason-dixon line. Most areas, see great spring buildup, a strong early spring flow, a dry period during July and August, then a flow which the bees use to raise fall brood. The 60 days, are the period the bees need to raise enough bees (3 full cycles) to have a large enough cluster of young bees to handle the winter period of 4 or 5 months.

Of course this is all based on location. But for the vast majority of beekeepers that actually go through winter beyond complaining of temps in the 50's, the seasonal cycle is really the same with little change. Those places without a fall flow, may need the beekeeper to provide it to the bees to ensure fall brood.

Remember, we keep bees where we want, And that may be at odds with what bees would select for themselves. Places with odd flows, no fall flow, or other severe environmental factors would see little success for thriving colonies. This is how nature works. Areas that are conducive to success are selected more , and those not conducive are selected less. You may find bees all over, but the losses in one area compared to the next would be drastically different. We of course do what we need to do to make them all survive.