A Berlin, Germany, group of researchers tested the effectiveness of insecticide impregnated fencing in keeping flies and biting insects away from pastured horses. The fencing was a mesh, 100 cm (39.4 inches) high, treated with 80 mg of deltamethrin per square meter and was UV-ray protected. Traps positioned outside the fencing showed at least a 60% reduction in bugs. Even more dramatically, filming of the horses on pasture showed average insect attack rates of 4.4 per horse on protected pastures, 7.6 per horse on partially protected pastures compared to a whooping 172.1 on unprotected pastures. The partially protected pasture had a total perimeter of 3,031 feet, with only a 406-foot section using the mesh.
We’d like more details, such as how large a pasture this approach can protect and how long the mesh lasts, but we’re intrigued. The advantages in terms of being able to protect one or a group of horses for a prolonged period without having to repeatedly apply repellents, and minimizing chemical exposure, are huge.