Any grass that is unwanted is a weed. Rye grass is typically used to thicken the lawn on golf courses when the Bermuda grass is dormant. However, it becomes undesirable when the Bermuda grass begins to grow again. Crabgrass is a common problem for many homeowners. It is especially difficult to eliminate because it enjoys the same things that desirable lawn grass needs to thrive. You can eliminate both grasses from your lawn with herbicides and natural remedies. It takes vigilance and persistence to effectively remove crab and rye grass from a lawn.
Take preventive measures for crabgrass. Spread a pre-emergent herbicide on the lawn before the weed can grow. The herbicide will eliminate the crabgrass as it begins to germinate.
Pull the crabgrass out by hand. Wet the lawn before you begin and wait for the soil to absorb the moisture. This will make the work easier. Ensure that you pull up as much of the weed's root system as possible.
Spot-spray crab grass with a chemical weed killer. It is important to spray the weed carefully to avoid killing your grass as well. Follow the directions on the product for best results.
Grow your grass long and thick. If you keep your lawn grass at a height of about 3 inches, the crab grass will not receive enough sunlight to thrive. Also, if your lawn is tightly packed with the grass you do want, there will be no space for the crabgrass to grow. According to Stuart Franklin in "Building a Healthy Lawn: A Safe and Natural Approach," crab grass dies naturally in the fall and begins to grow again in late spring. You can use this period to grow a thick, long lawn to prevent the crabgrass from coming back.
Water your lawn deeply to discourage crabgrass. This weed prefers shallow watering.
Use a herbicide. You can spot-spray rye grass with herbicides such as Glyphosate, Osprey and Hoelon. These are usually available from garden stores.
Let rye grass die out naturally. Ryegrass, a cool season grass, cannot survive high temperatures and will die in the summer heat. To accelerate the process, do not water the ryegrass for about two weeks in early May. You can begin watering again after the grass has turned brown.
Consider pulling rye grass out by hand. Wet soil will simplify the process of pulling the grass out, complete with roots.