Label says 1 oz per gallon per 200 square feet, even when using a backpack! One gallon for every 200 sq feet? Does that mean spraying far beyond run off, or what? How the heck will spraying that volume result in uptake by the leaves of the weeds? Is this stuff supposed to be soil drenched? I've tried to Google the mode of this herbicide, but have come up empty. The label does mention that mowing should be delayed, and 24 hours of no irrigation is stated. So, if it penetrates the foliage, why does it call for 1 gallon per 200 sq feet?