Oxalic acid (HOOC—COOH) — colorless crystals, well soluble in water. It is poisonous, has a sharp irritating effect on the skin, mucous membranes and respiratory organs.

Oxalic acid for the treatment of bees with varroatous invasion is used in two ways: by fine spraying of bees with a 2% aqueous solution or acid vapor obtained by its sublimation in a special device.

To prepare a 2% aqueous solution of oxalic acid, warm (30°C) boiled water is used (20 g of oxalic acid per liter of water). The solution is prepared before use.

To seal bees on honeycomb frames, full-honey and pergovye honeycombs are removed from the hive during processing. Then the honeycomb frames are taken out alternately and the bees are sprayed on both sides with any fine spray, the aerosol torch is directed directly at the bees at a distance of 35-40 cm at an angle of 43°. 10-12 ml of the solution is consumed for processing one honeycomb frame, completely incubated by bees. During processing, the uterus is isolated. Processing in multi-body hives begins with the lower body.

When bees are treated with oxalic acid vapors, the upper hatch is closed in the hive, and an oxalic acid vaporizer is introduced into the lower one. Consumption of 2 grams of the drug (for every 10-12 honeycombs occupied by bees).

Bee colonies are processed up to 5 times during the active season. When using an aqueous solution, the treatment is carried out at an ambient temperature of at least 16°C, and when treated with acid vapors, using an evaporator of at least 10°.With spring and at least 2°C in autumn.

Precautions:
1. Persons who have passed special instruction are allowed to work with oxalic acid. Processing of bees is carried out in overalls and protective equipment (bathrobe, rubberized apron, respirator or gas mask, boots, gloves, goggles).
2. It is forbidden to smoke, take food and water during work. After work, the overalls are removed, the face and hands are thoroughly washed with warm water and soap. If acid gets on the skin, it is washed off with water or neutralized with a solution of baking soda.
3. Storage and transportation of oxalic acid together with food and fodder is prohibited.
4. When using heaters, observe fire safety measures.