Lawn Care Liquid Solution Ingredients?

Question

My neighbor's hired a lawn care company to get rid of all the weeds on their lawn. They sprayed this yellow-tinted liquid onto their lawn, which killed off all the living plants, weeds or grass. They then spread seedlings directly on top of the dead, dry matter, and new grass began to grow on top.

What do you guys think that the liquid they sprayed was made of? Like, what kinds of substances could it contain?

Answer 1

He essentially sprayed round up if everything was killed.  The active ingredient in it is glyphosate.