Three hundred bees. Divide the mites by three.

Count first. Treat if the number says so. How to Quantify Varroa destructor is the UF/IFAS method page. Jack, Sperry, Mortensen, and Ellis. The infestation rate is mites per 100 adult bees. Collect about 300 bees from a comb where adults are emerging. A 300-bee sample fills about 1/2 cup, 100 ml. Mark the jar. Do not take the queen. Divide the mite count by three if you actually hit 300. the mite species page is the animal. Varroa is the Florida month. This page is the jar.

In general, infestation rates reaching 2% to 3% should be treated promptly.

Alcohol wash or sugar shake

How to Quantify Varroa destructor names three dislodging agents: 70% isopropyl alcohol, non-sudsy soapy water such as windshield washer fluid, and powdered sugar. None is better at knocking mites loose. Alcohol and soap kill the bees and let you count both mites and bees. Sugar does not kill them. You dump them home. The count is an estimate because you never count the bees. A pint jar with 1/8 inch mesh in the lid for a 300-bee sample. Get this. Sugar for the shake: two tablespoons through the screen, roll the jar, rest two minutes in the shade, invert and shake one minute over a white plate.Get this.

Alcohol wash: fill the jar one-half to three-quarters, lid on, shake 30 seconds, dump onto 1/8 inch mesh over a white plate, rinse, count mites, count bees. Example on this paper: 15 mites and 325 bees is 4.6 mites per 100 bees. That is over the 2 to 3 percent line. Treat. Then sample again to see if it worked.

A sticky board is a different number

How to Quantify Varroa destructor: natural mite fall samples the whole colony. Accuracy depends on how much brood is emerging. Unless you know colony size, be cautious treating from fall alone. A 3,000-mite estimate wrecks 10,000 bees and matters less to 50,000. That is why this paper favors infestation rate. Varroa still uses 3 mites per 100 bees for this band. The Honey Bee Health Coalition table this paper reprints uses 2 to 3 percent as the prompt-treat line. Use the jar. Then read the label.

Shake the frame into a 9 by 13 pan if scraping is messy. Pour into the marked jar. Tap. Add or remove bees to the 300 mark. Viruses still ride the mite. viruses is that list.

Sources

1. How to Quantify Varroa destructor. Jack, Sperry, Mortensen, and Ellis. 300 bees. 2 to 3 percent.
2. Varroa destructor. The species page.
3. Florida Beekeeping Management Calendar. 3 mites per 100 bees on the Central Florida table.

Varroa does not take a Florida winter offThe animal is still the mite species page.