The best way to prevent weeds is to use polymeric sand, which hardens and blocks weed growth when activated with water. If you're using regular sand, you'll need to refill and compact it more often. Keeping the surface clean and free of debris can also help prevent weed seeds from settling in the joints.

Some of the particular herbicides that work best to get rid of nut grass without killing the grass include Halosulfuron-methyl, mesotrione, sulfentrazone, and metsulfuron. A herbicide like glyphosate would kill nutgrass, but it will kill nearby plants, too.

There are several ways to kill poison ivy permanently. The trick is to keep it from coming back. Herbicides and natural remedies are highly effective for killing existing poison ivy plants. However, plant and root parts left behind can easily create new sprouts that turn into full-grown plants. The only way to permanently get rid of poison ivy is to be patient and diligent until all traces of the plant are dead and gone.

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.