: English bluegrass, Wiregrass, Flat stem bluegrass
: Introduced to North America as a forage plant possibly in the late 1800s.
: Rhizomatous, slender, erect, perennial grass that grows 3/4 to 2 feet in height and produces both fertile and infertile shoots.
: Blades are up to 4 inches long, 4.5 mm across, and rather stiff; dull green or grayish blue in color, hairless or sparsely pubescent and flat or slightly twisted. Tips are hull-shaped. Leaf sheaths are grayish blue or dull green, somewhat flattened, hairless or sparsely pubescent. Terminates in open panicles.
: Solitary or tufted with 4-6 alternate leaves along each fertile stem. Green or grayish blue in color, hairless, somewhat flattened and unbranched.
: Open panicle of spikelets, 4-6 mm long and 1.5 mm across, somewhat flattened and mostly grayish blue; each spikelet consists of a pair of glumes and 3-7 lemmas. Glumes are 1.5-2.5 mm long, oblong-lanceolate, curved, grayish blue, and longitudinally veined. Lemmas are 2-3 mm long, oblong-lanceolate, curved, light to medium green, and 3- or 5-veined. Lemmas are hairy along the lower half. Blooms during the summer, lasting about 1-2 weeks. Becomes tan as it matures.
Fruit and seeds
: 1.5 mm long, ellipsoid grains that are grooved along one side and light tan to brown in color. Seeds remain viable in the seed bank for up to 4 years.
: Native to Europe. Found in fields, disturbed areas, pastures, roadsides, vacant lots, yards or gardens.
: By seeds and rhizomes.
: Kentucky bluegrass (Poa compressa
) can be distinguished from P. pratensis and other Poa spp. by its flattened stem and its blue-green color. Also, the rhizomes of P. compressa originate below ground and turn downward, but those of P. pratensis start from above ground before turning downward.
Monitoring and rapid response
: Hand pulling or careful hoeing can be effective in spring or early summer before seeds set. Use of herbicides is not typically recommended as they occur in mixed stands together with native species. However, glyphosate or atrazine can be used in open areas with caution. Burning can be effective in late spring when plants are 1-2 months old.
: The information provided in this factsheet was gathered from the Invasive Plant Atlas of New England and Illinois Wildflowers.
Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (http://www.invasive.org).Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (http://images.google.com).