Feeding garlic does work to about 85% efficiency.
Do NOT feed raw garlic as it is the allicin (sp?) in raw garlic that can possibly cause anemia.
Processed garlic is good to feed as the allicin has been processed out of it.
You (because you live in tick country) might want to start feeding it right now - lol lol
Feed garlic powder, not garlic salt. I buy equine garlic from Herbal Remedies for Horses including Natural Equine Supplements for Laminitis and Founder in Horses- Herbs For Horses
I have been buying various products from this company since 2004. They are privately owned and great to do business with. They have reining horses (which perform barefoot by the way lollol) so I figure they started this company up for their own needs.
They are in Memphis, if I call early enough in the AM, my stuff is at my doorstep, sometimes the next day I start with about one teaspoon daily and work my way up to a tablespoon daily. Is a tablespoon an ounce?
That being said, I cannot feed it to my horses with ulcers and I wouldn't feed it to a horse prone to colic.
Repel-X works great IF you mix it, according to the label, specifically for ticks. You'll get about three pasture days from spraying. However, that much strength burns all of my horses
Zonk! Works pretty good but during the height of the tick season, I have to use it every day.
What the horse is being fed can also make a huge difference, as what they eat permeates thru their skin. Sweet feed is the worst thing on earth for being a bug magnet.
As far as trail riding, I found Deep Woods OFF!, in the green can, always worked really well for both of us.
It's easy to pack and you only need one can of something to protect yourself and your horse, as long as the horse doesn't have a reaction to it.
I have heard good luck stories using a sock full of sulphur and powdering the horse's legs but if you cross a creek, I don't think enough powder residual would stay on the horse.
Last year was a very quiet tick year for us, I'm expecting this year to make up for that since I have already pulled a tick off one of the horses.
I have two that are tick magnets.
Then there's the chiggers. They don't like me one iota but will line up on the garage apron to attack Mr. WTW the minute he walks out the door