ditto what jkt said. i could buy roundup (or a generic) for about 70 or 80 bucks a gallon, but for about 20 or 30 dollars more i could buy 2.5 gallons.

this was a 41% concentrate of glyphosate, which is basically roundup pro. if you buy the generics (like honcho) they do NOT come with surfactants in it. you can add your own to the mixture if you want. (surfactant = a few oz of dishwahing liquid per quart of concentrate).

2.5 gallons will cover 10.0 acres with a 1.5% solution of the mix. it' s basically one quart per acre, mixed in with about 15 gallons of water. a 2% solution will kill most vegetation that is about 6" is shorter.