Quack grass (Elytrigia repens) is a perennial grass with 1/3-inch wide blades and hollow stems. It grows from underground rhizomes. Quack grass seed spreads through contaminated turf seed, birds, wind and even mowing. One quack grass plant can produce 300 feet of rhizomes a year, according to turf specialists at American Lawns. The only way to kill quack grass is with an herbicide containing glyphosate. Unfortunately, these nonselective herbicides will kill the lawn as well, so you must carefully apply them. Apply the herbicide when the quack grass is actively growing.
Fertilize the lawn with 1 lb. of nitrogen for every 1,000 square feet. Water and care for the lawn as you normally do. Wait two to three weeks to apply the herbicide.
Spray the herbicide directly on the quack grass until it is soaked. Do not water the lawn until the next day.
Reapply the herbicide in 1 month.
Wait two weeks to pull up the dead quack grass.