There are organic herbicide options that will kill grass but not flowers, including white vinegar or a dish soap solution. Commercial selective herbicides can also target grass over other plants, but read the instructions carefully to avoid damaging your garden. Herbicides that kill grass but not flowers usually include ingredients like clethodim and sethoxydim. Otherwise, your best bet will be to weed by hand.

Lawns with steep slopes can benefit from having quack grass. Quack grass's long roots and runners can help to prevent soil erosion on hillsides. Additionally, bird lovers may enjoy the fact that quack grass seeds are an attractive food choice for their avian friends.

Foxtail self-seeds and dispurses them among other grasses and pastures. The seeds can spread by wind and by attaching themselves to animals and humans. Seeds will germinate in their new location and become a new plant, which continues the spread of foxtail. Unfortunately, foxtail spreads easily, making it difficult to remove unless it’s caught quickly.

It’s not legal to intentionally damage a neighbor’s tree. Even if the roots of a tree encroach into your yard, if you damage or kill a tree that belongs to your neighbor, you can be held liable for the damage in most cases. Since herbicides can spread through the tree, causing damage to the whole tree and not just the roots that are on your side of the property line, you shouldn’t poison your neighbor’s tree. The other downside to this method is that if the tree dies, it can fall onto your property and cause more damage, so herbicides are best avoided in this circumstance.