Noxious weeds can be poisonous or act as an irritant to humans, but not all are directly harmful. However, indirectly, noxious weeds also compete with native species, effectively affecting our local ecosystems of plants, pollinators, and other animals.

Landscape fabric and a few inches of gravel should be enough to put under a deck to prevent weeds from flourishing. If you don’t want to invest the time and money on a project like this, you can regularly spray the area underneath your deck to kill weeds.

Herbicides containing a combination of the active chemical ingredients dicamba, fluroxpyr, and quinclorac are most effective at purging your turf of white clover. However, for small home lawns, organic prevention and control can be very effective methods for killing clover weeds and save you from using harmful pesticides that might damage your lawn.

Glyphosate and other non-selective herbicides can kill orchard grass, but they will also kill the surrounding plants. Also, not all areas allow the use of glyphosate due to its environmental impact—which the EPA describes as a "potential risk to terrestrial and aquatic plants and birds, and low toxicity to honeybees." Consider mechanical removal to target the plants specifically.