Oxalic acid vaporization

Vaporize oxalic acid dihydrate crystals inside the hive using a heated wand to kill phoretic varroa mites on adult bees. Most effective during broodless periods in late fall or winter when all mites are exposed.

Why It Works

The vaporizer heats oxalic acid to ~157°F (70°C), releasing a fine vapor that crystallizes on hive surfaces and bees. Mites contacting these crystals suffer fatal damage to their mouthparts and footpads. During broodless conditions, a single treatment achieves 90-97% mite kill.

Tips

• Timing is critical -- treat when the colony is broodless (typically late November to December in northern climates) for maximum efficacy
• With brood present, repeat 3 treatments at 5-7 day intervals to catch mites emerging from cells
• Use a 12V car battery to power the vaporizer at remote apiary sites
• Always wear an OV/P100 respirator -- oxalic acid fumes cause serious lung irritation