Fight against varroa: oxalic acid, an effective and affordable solution
What is Oxalic Acid?
Oxalic acid is a chemical compound with the formula C2H2O4. It occurs as odorless white crystals that are soluble in water. It is naturally found in many plants, such as sorrel, spinach, and rhubarb.
It acts as an acaricide by disrupting the metabolism of varroa mites, leading to their demise.
Advantages of Oxalic Acid Treatment:
Effectiveness: Oxalic acid is a highly effective treatment against varroa, with a mite mortality rate of up to 98%.
Economical: Oxalic acid is a relatively inexpensive product, making it accessible to small-scale beekeepers.
Easy to Use: Oxalic acid treatment can be carried out by novice beekeepers, provided that they follow the instructions and safety precautions.
Bee-Friendly: Oxalic acid is generally well-tolerated by bees when used correctly.
Limits of Oxalic Acid Treatment
Variable Effectiveness: Dependent on application method, concentration, temperature, and varroa stage. Varroa mites can develop resistance.
Impact on Bees: Can be toxic if misused. Possible side effects include disorientation, mortality, and weakening of colonies. Not recommended in the presence of capped brood.
Risks to Applicator: Irritating to skin and eyes. Wear protective clothing.
Honey Contamination: Possible if dosages and precautions are not followed. Contaminated honey is not dangerous but unfit for consumption.
Legal Restrictions: May exist in certain countries. Consult local authorities.
When to Perform Oxalic Acid Treatment
The ideal time for oxalic acid treatment against varroa is generally between November and February, in the absence of capped brood and when the ambient temperature is above 7°C.
In winter, colonies are smaller, and varroa mites are more accessible, making treatment more effective.
It's important to choose a day with suitable temperatures to avoid stressing the bees.
Additionally, it's common to apply this treatment after honey harvest to prevent honey contamination and just before the intensive egg-laying period in spring to reduce the varroa population before it increases with new brood. Monitoring varroa levels throughout the year and treating when they exceed acceptable thresholds, while respecting recommended treatment intervals, is essential to avoid overexposure of bees and the risk of mite resistance. Climatic conditions, especially humidity for the sublimation method, should also be considered to ensure treatment efficacy.
Preparation of Oxalic Acid for Varroa Control
Important: Before handling oxalic acid, carefully read the instructions and safety precautions of the product you are using. Wear appropriate protective clothing, including gloves, goggles, and a respirator mask.
Preparation Methods:
- Aqueous Solution:
- Dissolve 35g of oxalic acid dihydrate in 1 liter of warm water (about 40°C).
- Stir until completely dissolved.
- Allow the solution to cool before use.
- Oxalic Acid Syrup:
- Mix 30g of oxalic acid dihydrate with 300ml of warm water (about 40°C).
- Add 300g of sugar and stir until completely dissolved.
- Allow the syrup to cool before use.
- Sublimation:
- This method uses a specific device to sublimate oxalic acid, converting it directly into gas.
- The gas is then diffused into the hive.
- This method is more technical and requires specific equipment.
Stop Varroa: A Safe and Effective Oxalic Acid Treatment
If you were told about a safe and effective oxalic acid-based treatment that doesn't poison your honey and is safe for your bees... Well, we're talking about Stop Varroa!
Stop Varroa treatment ensures a high success rate, close to 100% if applied correctly. Simply lift the frames one by one and spray both sides with the product. The varroa mite colony will then be decimated within 24 hours.
In conclusion, oxalic acid is an effective and affordable treatment against varroa. By following best practices and taking necessary precautions, beekeepers can use oxalic acid to protect their colonies and contribute to bee health.