Quackgrass is an erect, sod-forming perennial. Stems (culms) grow 1 to 3.5 feet high.
The leaves are up to 3/8 inch wide (10 mm), flat or u-shaped and from 4 to 8 inches long with a twist near the tip. The upper surface may have fine sparse hair over the veins, the underside is usually smooth. Primary blade veins are prominent and widely spaced, with much less prominent secondary veins in between. Leaf blades are sometimes concentrated at the base of the plant.
Sheath, collars and ligules: The sheaths of the lower leaves may have sparse hair. Auricles are present, but small - 0.3 to 1 mm. Ligules are also small - 0.25 to 1.5 mm long.
The inflorescence is a single erect terminal spike, up to 6 inches long and up to 0.6 inches wide.
The flower spikelets on the inflorescence are upright and usually tight against the spike, but may be ascending. Spikelets are 10 to 27 mm long with 4 to 7 florets. The glumes are oblong, usually smooth, keeled in the upper part. The upper and lower glumes are almost of equal size: The lower 8.8 to 11.4 mm with 3 to 6 veins; the upper 7 to 12 mm with 5 to 7 veins. Lemmas are about the same size as the glumes, mostly smooth, with or without awns. If present, awns are 0.2 to 4 mm long. Florets have 3 anthers.
Invasive: Quackgrass is native to Eurasia. It is considered quite invasive.
Habitat: Quackgrass is an erect, sod-forming perennial that grows from long yellowish-white rhizomes, as well as by seed. It is a plant of waste places and sometimes in cultivated fields and is very drought tolerant.
Names: The genus Elymus is taken from the Greek elyo, meaning 'rolled-up', being a name for a type of grain where the lemma and palea are tightly rolled around the seed. The species name repens means 'creeping', here referring to the creeping rhizomes of the root, allowing the plant to quickly spread from a point of origin. The author names for the plant classification are: First to classify was “(L.)” which refers to Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy. His work was updated by ‘Gould’ which refers to Frank Walton Gould (1913-1981) American Agrostologist, ending his career at Texas A & M University where he was head of the Tracy Herbarium. He authored 80 papers on grasses and four grass manuals including the textbook Grass Systematics.
Comparisons: The only other species of Elymus close in appearance to this is Elymus hoffmannii, Hoffman's Elymus, not found in Minnesota, and developed as a forage grass. Other species of Elymus found in the Garden are Eastern Bottlebrush Grass, Elymus hystrix and Wild Rye & Canada Wild Rye, Elymus sp. & E. Canadensis.
Above: Quackgrass group - Photo ©Josh Sulman, Wisconsin Flora. Drawing by Dr. Otto Thome, courtesy Kurt Stüber's Online Library.
Below: 1st photo - The tight spikelets of the flower stalk. Photo ©Phoebe Waugh. 2nd photo - Spikelet detail; 3rd photo - floret detail. Both photos ©Anna Gardner, University of Iowa.
Quackgrass is a non-native species found throughout the United States and Canada and in Minnesota it is found in the vast majority of counties with the exceptions widely scattered. An immigrant from Eurasia. It is one of nine species of Elymus found in Minnesota and the only non-native species. The others are mostly all species of rhy grass.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"