This will kill seeds, full grown trees, and any vegetation growing in the area or that has roots growing into the area. It also runs off with rain and will kill what it runs off to. 5-10 gallons per acre in a wetting spray.
What has worked well for me for total vegetation control is 10 lb Sahara DG, 2 quarts Garlon 4, and 1 quart Reward. This is not as likely to run off and kill things downstream, however it must not be used over the root zone of desirable trees.
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
Benjamin Franklin 1775
Sell not virtue to purchase wealth, nor Liberty to purchase power.
Benjamin Franklin Poor Richard's Almanac1738