Sawyer Tick repellent on horses?

Ticks. They are everywhere where I am.

I am experimenting with Equi Spot, and keep guinea fowl, but I was looking into the Sawyer fabric treatment for myself and noticed you could use it on dogs. https://www.sawyer.com/page/dogs-and-permethrin-insect-repellent

Has anyone used it on horses? I was thinking I could at least put in on the tail hair so they weren’t crawling up the tail… It says it lasts 6 weeks on dogs, which is quite attractive.

My mare has an Amigo flysheet (with “Bug Buster” technology). It turns out that Bug Buster technology is essentially that the sheet has been treated with permethrin.

Permethrins are also a common ingredient in fly sprays for horses. Absorbine’s UltraShield (black bottle) has it for example.