Pulling weeds once per month is typically often enough to keep most weeds at bay. But in general, it's best to pull weeds as soon as you spot them to prevent deep root growth and slow their spread. To make it easier, plan your weed pulling after rain or after the sprinklers run so the soil will be nice and wet and the weeds will be easier to pull. If you notice moss accompanying weeds, make a plan to remove the moss immediately to prevent damage.

Johnsongrass and crabgrass are invasive weeds that can overtake your lawn. Crabgrass is a low-growing grass most often seen in lawns, flower beds, and vegetable gardens. While you may find Johnsongrass growing in your lawn, it will also grow in pastures, crop fields, and the edge of the road. Johnsongrass is much coarser than crabgrass. If left alone, Johnsongrass can grow up to 8 feet tall. 

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.

Yes, organic herbicides and natural prevention methods reduce chemical use.