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Biting Fly repellent

Does anyone have any suggestions for a biting fly repellent? I work on a ranch in Montana and we have a serious problem with horse flies and deer flies. The bites turn into welts when I get bit. I have tried the plant based insect repellents, but they do anything to deter the flies.

3 Replies

Great question @kenziek13!

Anything with Picaridin in it is rated to repel all types of flies, biting and otherwise so I would start there. Deet based products are most effective with mosquitoes but can be hit or miss with flies depending on the kind of fly. 20% Picaridin is full-strength, anything higher than that will only extend the protection over time, not increase the protection. Hope this helps!


At REI, we believe time outside is fundamental to a life well lived.

I agree with picaridin, the lotion lasts the longest and stays on fairly well through moderate sweat or light rain.


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When Summer hiking in NY State Parks I have found Ultrathon to be effective. It is a lotion and somewhat greasy, but it works and is long lasting.