Blackflies and horseflies: why "mosquito" products don't work against them
Different insects respond to different substances, and there is no universal answer.
In July, particularly near water and in hot, humid weather, blackflies and horseflies become a greater concern than mosquitoes. This is when shoppers make an unpleasant discovery: their usual "mosquito" product is noticeably less effective.
The reason is simple. Different insects locate people through different signals and respond differently to repellents. A formulation and concentration that reliably repels mosquitoes may have almost no effect on blackflies. Blackflies do not simply bite but cut through the skin, and they are also less responsive to scent.
What this means in practice:
- check the packaging to see exactly which pests the product is intended for — the specific types are usually listed;
- for blackflies, choose formulations with a higher concentration of active ingredient;
- to protect against horseflies, which land on exposed skin and clothing, treat clothing as well as the skin;
- remember that treating an area against blackflies is almost pointless — they disperse over long distances from flowing water.
One simple but effective point: blackflies are most active in calm weather in the morning and evening, while horseflies are most active in hot, sunny conditions, near water, and around livestock. Scheduling work on the property accordingly can reduce the problem just as effectively as pest control products.
