If you are using Chemicals to control weeds, beware! Herbicides are developed for a particular job. Some herbicides are called Selective Herbicides which will target a specific plant while not harming another. For example, to kill a weed but not the grass or kill grass but not a plant. There is another group of Herbicides which are called Non-Selective. These guys kill everything. Glyphosate(Round Up) is the most popular in this category. You have to be very careful while using these types of herbicides as the photo's below will show.
Oh, and before you ask. No, I didn`t do this. It was the home owners.