Don't make this mistake. One of my customers was using Ortho squirt bottle hand weed sprayer. Worked fine, but he ran out. Soo...he bought a bottle of Weed-B Gone and refilled his squirt bottle with it ...and sprayed about 30 additional weeds. He added no water.
Whoops; he killed all 30 spots. He did not dilute with water as the directions require. He applied the product at approximately 20 times the correct rate.