I used to coon hunt with my dad years ago, and he always made us wipe ourselves down with vinegar. After you get past the smell, it works.
My wife and I bought a little piece of property on McGee Creek Lake, in Oklahoma about 6 or 7 years ago, and beleive me, it was a wilderness.
We had to do lots of tree cutting and removal of underbrush, so we coated ourselves with vinegar before starting work every day, and never used any repellant other than that, and we have not had any problems with chiggers,seed ticks, or mesquitos.
Also if you are around poison ivy it works to nuetralize the oil in the plant that causes you to break out. It also works well to wipe off your exposed skin with after coming out of the woods, as it removes any poison ivy or seed ticks and chiggers that may have gotten on you while your hunting.
Can't hardly use it when hunting any kind of game that is scent wary, but it works great for squirrells and rabbits, as well as birds.