Usually the commercial variety will also have a surfactant which helps the product stick to slippery leaves and become rain fast.
You can buy Surfactant separately and add it - just a tiny bit goes a long way - less that 1/8 oz
How fast it works depends on the brand - some are better than others - but avoid the powdered varieties. Also depends on the temperature and percentage you mix ; cold weather: 50-75deg would be 8-6oz gal, 75deg -up, 3-4oz gal; also mixing some Amine 400 2, 4-D in equal proportion seems to help take out those pesky tree seedlings that pop up in the early spring. Low percent Amine 400 2, 4-D does not kill grass. 6oz in early spring when chilly and 2 oz in summer per gallon.
Great info. Thanks!
I used 4oz per gallon which was a bit strong but definitely works. I hadn’t considered temp.