>So then, How soon should one use some preventive treatments?
I don't do preventative treatment for anything. Bees or me. Do you take antibiotics when you're not sick?
> Like the patties.
There are two kinds of patties commonly used, neither of which I use. Grease for Tracheal mites and terramycin for AFB. The solution for Tracheal mites is resistant bees. The solution for AFB is strong hives and burn the combs if you get some. Terramycin will only mask the symptoms and will NOT kill the spores. Both have grease and will attract small hive beetles.
> Should I be determining the infestation or just regular treatments?
Finsky will do regular treatments. I would learn to monitor the mites. This can be done with several methods either individually or using all of them. You can do a sugar roll:http://entomology.unl.edu/beekpg/tidings/btid2000/btdjan00.htm#Article2
A sticky board:http://www.tonitoni.org/photos18.html
Or just count natural mite drop on a Screened Bottom Board.
> I know what to look for when mites have caused problems but I sure don't like the idea of waiting to see the sick bees.
Don't. If you wait to see sick bees you've waited too long.
> From what I read on this great forum, the thing to do is a much closer inspection of the brood. I'm not sure I'm good enough for that or fast enough.
That's another thing you can do is ucapp some drone brood now and then and count mites there. What is "fast enough"? They don't run.
>The temperatures have finally reached the 60's to 70's for daytime highs so I'm planning on a longer and closer inspection this weekend.
I appreciate the replys. Thank you.
My recommendation is get on a natural system:http://www.bushfarms.com/beesnaturalcell.htm
And monitor the mites to make sure you don't have a problem. You may not need to do anything. If the mite numbers are going up exponentially and reaching numbers of say 50 mites dropped naturally (untreated) in 24 hours then you should have a plan in place to deal with it. If you want to stay totatlly natural (and not add anythying) you can cut out all the capped drone, or put in a drone foundation frame and take it out and freeze it when it's capped. You can do a break in the brood cycle by caging the queen. You can use powdered sugat dusting. Or, if you want to use soft chemicals I'd recommend vaporizing oxalic acid. The problem is that treating while there is brood isn't very effective:http://www.bushfarms.com/beesvarroatreatments.htm
So your best bet if you find your colony has a serious problem during brood rearing time, might be a combination of things. If you hit them with powdered sugar off the bat you'll knock some down. If you cut out all the drone brood you'll knock them down some more. If you confine the queen for three weeks at the same time and wait three weeks the worker brood (which is all the brood that is left because you cut out the drone brood and you can cut it out again when the open drone brood get's capped) When there is no brood you can do oxalic acid vapor and kill virtually all the remaining mites.
The time to treat with anything is when the hive is broodless in the fall. Powdered sugar, oxalic acid etc. It's your choice. I'm not willing to contaminate the wax with organiphosphates (Checkmite) or Fluvalinate (Apistan).