Quack Grass

Quack Grass/Quackgrass (Agropyron repens) , (Elytrigia repens)

With so many names given to this weed grass, the more common names for this cool season perennial include Witch grass (not to be confused with Panicum capillare), Wheatgrass, Quick grass/quickgrass and Couch grass/Couchgrass.

Similar in appearance to crab grass, Quack is thicker and grows up to 3' tall. It is native to Europe and the belief is that it was introduced to North America by accident in the 1600's. It dominates quickly, hence quick-grass, and by the mid 1800's was determined to be a serious problem throughout Canada and the United States.

Because it prefers cooler climates, this grass grows abundantly in the north-east and along the west coast. It doesn't grow as much in the southern states.

This grows quickly, is clump forming and dominates gardens.

Thin jointed hollow stems begin to clump from the base of the plant and on top are wheatgrass-like spikes with awns, or short tails. The wheat-like seed heads can be both densely or loosely structured.

Photo: Matt Lavin

Grass blades are narrow (about 1/4" wide) and bluish-green in color
and have a rough upper surface.

What distinguishes this from other weed grasses are the claw-like auricles. An auricle is a pair of tiny claws that hug the stem at the base of the leaf blade.

Photo: Matt Lavin

Quack Grass is that is allelopathic. Allelopathy is when a chemical is released from a plant where it kills the seedlings of other plants or stunt the growth of plants. Chemicals are released from the roots and from fallen leaves where toxins seep into the soil. A strong hint that a plant is alelopathic is the bare, or exposed soil beneath it.

Weed grass is herbaceous, or dies back in winter, and grows back early spring. It spreads by seed and root rhizomes and prefers sunny, open areas and adapts to all types of soil, especially sandy soil.

Because it is competitive and allelopathic against other plants, Quack grass is very difficult to eradicate and will easily crowd out native species. It can quickly take over newly seeded lawns or any exposed soil.

When pulled, if rhizomes are left in soil they become stimulated to grow.
If removing manually pull or dig plant and try to get as many rhizomes as possible. Remain diligent by doing so regularly.

This video is good for the gardener to understand the weeds growth and method of manual removal in your garden.

If location of grass is in a flower garden that isn't established, till area and put weed killer on it, getting rhizomes to. Don't let it get so tall that awns release seeds. After two weeks mix in rich soil and then place mulch on top. An organic option is black plastic mulch which will take longer.

If weed is in lawn try mowing frequently to help damage blades where weed won't grow as quickly. If there are only small patches in a lawn it may be more effective to dig out and kill weeds then lay sod down. Seeds have mild difficulty resurfacing through densely (newly layed sod).

Non-selective post-emergent chemicals are the only chemicals that have an effect on weed. More specifically glyphosates. Pre-emergents are a waste of time and money because of the rhizomes.

Serious invasions may require smother crops, such as buckwheat in spring and turn under before it goes to seed.

Throw out weed, don't put into a compost pile.

FYI: