Follow the Clean Slate Approach! Avoid mite kills successfully.
This philosphy embraces the idea that the only good mite is a dead mite. Mites can kill by reproducing in the hive, but they
can also take out a hive that was effectively treated... yesterday. Today, the stinkers are robbing a dying hive, and bringing back
more than honey! Yep, that happens, just about any season. A swarm you missed in May becomes a mite bomb by October. Or by the
following May.
There are two components of this philosophy:
- Always treat for mites when the hive is broodless, such as when you make a split, or in the fall/winter.
- Assume that a mite influx will happen spring, and summer, and fall (unless you are measuring the mite population with the alcohol wash.) Treat once in the spring, once in the summer, and once in early fall to kill mites from a mite-riddled colony your hive might have robbed.
Treating to the Mission, not the Threshold
Mission: Safeguard New Hive
When a package or nuc arrives at your apiary, this is the time to address mites. Your options are plentiful for a
package: Oxalic Acid
Dribble, Apivar,
or Oxalic Acid Vaporization.
A nuc has capped brood; no OAD and OAV will be at least 50% less effective. Apivar is the best bet. The other
treatments a package can use are more like a band-aid.
Be sure to clear the removeable bottom board before you treat, if you have a screened bottom board,
and then count the dead mites that fall due to the treatment over a 2 week period. You'll be amazed.
And dismayed.
Mission: Remediating a Hi-Mite Hive During Honey Collection
If you have just realized your hive has ANY mites in an alcohol wash in the summer, when the
hive has capped brood, use
Formic Pro.
Just be conservative about treating if the temps will be above 79 degrees F - and do not use this option with a new queen.
Treating with Formic Pro is often a band-aid. Plan to treat again in fall ASAP, after honey collection.
Then you have more treatment options, even if the hive still has brood.
Mission: Fall Protection
Remember, these steps require that you not have honey supers on for honey for sale.
First, mop up any mites that emerged over the summer. Treat
with Oxalic Acid
Dribble or Oxalic
Acid Vaporization in mid-early Sept. That's right, I'm recommending you
squirt Oxalic
Acid-laced sugar syrup on the bees in the cold. This treatment has been used
for decades in Europe
to good effect, and if only used every 6 months, does not harm the adult bees.
Be sure to count that mite drop post treatment for this first phase!!! It's so informative about
whether your spring/summer mite management strategy is working. You want to see fewer than 500 mites fall here.
Second, it is vital to eliminate potential extra mites brought in by your
hive robbing another that is dying of mites.
They can go out on a fly day, after the regular bee season, as late as Nov and pick up enough mites to kill the hive.
Two options here:
1) OAV administered twice a month through Oct and early Dec, to protect against mite influx. 3 times minimum.
2)Apivar
placed in the hive in early Oct, which protects the hive through Nov. The strips must be removed sometime before Dec is over.
This MUST be followed by Oxalic Acid Dribble. This is what the school of hard knocks has taught us Northern beekeepers.
Treating to the Mission: tailor mite managment to the situation at hand
Let's go more in-depth about the tools available for mite treatment.
See this
link from the HBHC for a short free book about your options and how to think about varroa.
If I don't mention a tool that appears elsewhere, it's because I cannot in good conscience give any support
to that method.
And I am not going into the details of deploying the treatment; click the treatment
to go to a site for that info.
Oxalic Acid Dribble: BROODLESS
and NOT OFTEN. This is a great option for a new package, or the fall treatments. WARNING: this will kill open
brood, and the hive must be well fed, so for a package, temps should be warm enough outside that they have been sucking
down sugar syrup (lows in the low 50s, no cooler). An overwintering hive or a well-fed split should not be vulnerable to
sucking up the oxalic-acid laced sugar syrup. Be sure to count the mite drop on the bottom board 2 days later!
Apivar: ANYTIME but
NO HONEY FOR SALE. is a strip that contains the same ingredient in Frontline pet collars, which is Amitraz.
Bees must walk on it, so place accordingly. You must remove the strip after 60 days, which is do-able but a
pain in the fall. Mite drop is over an extended period, so it's less informative
Oxalic Acid Vaporization: is
my preferred method, for hives without much capped brood. WARNING: this can kill you. There is no safe
"upwind". The vapor lands on any wet surface and turns to a strong acid. Your eyes and lungs are wet surfaces. Wear the pro.
I like the 3M 5203 Medium Respirator Organic Vapor Acid Gas Mask , find it on Amazon, like $30. Again, mite drop 2 days
later will tell you a lot!
One caution: since you're sticking a hot piece of metal into the hive entrance, check for comb
hanging down from frames, or growing from the floor: bring a flashlight, smoker, and hive tool.
None of these highly effective options can be done with honey supers on, which is where the importance
of not needing to treat in summer comes in. Killing off an increased mite population is really challenging.
It's easier to make a big dent in the mite the population when it is small.
Do I have to check for mites?
Welll.... only if that information is important to you for making a decision.
An Alcohol Wash uses a vessel with mesh that holds about 2 cups
of rubbing alcohol for a quick and painless kill of bees and mites.
Don't want to kill bees? Remember that bees act to defend their hive, despite their death. This is another
way their death serves their hive.
Looking at the mite drop during a day, or 2 days, or a week of "normal hive operations" is reflecting
how many dead mites are being cleared out of brood cells - more proportional to the presence of brood rearing, rather
than anything about how many mites are in the hive.
If you have honey supers on, and are wondering if your hives are in danger, if it is worth the time, money and effort necessary for treating...
then it's probably worth checking.
If it's fall, just treat!
Clarify things? ;) You can manage mites successfully without checking for them with an alcohol wash.
You can learn more about saving money and time due to unneeded treatments that season, if you check for mites.