I'm using "real" Roundup and the answer might be different for the generic stuff.
If I mix up say 2 gallons according to the label directions and have half leftover in the sprayer, does it go bad with time? If so, how fast?
It's convenient to have it in the sprayer so I can just grab it after work and hit a few weeds here and there. Get them while they are young.
But if the mixed solution loses strength after mixing perhaps I'm wasting my time.