Poa annua

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Poa annua
Poa annua.jpeg
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Clade: Commelinids
Order: Poales
Family: Poaceae
Subfamily: Pooideae
Genus: Poa
Species:
P. annua
Binomial name
Poa annua
L.

Poa annua, or annual meadow grass (known in America more commonly as annual bluegrass or simply poa), is a widespread low-growing turfgrass in temperate climates. Notwithstanding the reference to annual plant in its name, perennial bio-types do exist. [2] This grass originated as a hybrid between Poa supina and Poa infirma . [3] Major chromosomal rearrangements after polyploidy have contributed to variation in genome size in Poa annua. [4]

Contents

Poa annua as a weed in city and urban ecosystems Poa annua in urban areas.jpg
Poa annua as a weed in city and urban ecosystems
Poa annua as a turfgrass for use on golf course putting greens Poa annua for golf course putting greens.pdf
Poa annua as a turfgrass for use on golf course putting greens

Description

It has a slightly creeping, fibrous, rootstock. The stem grows from 15–25 cm (6-10 in.) high. It is slightly flattened, due to being folded rather than rolled.

The panicle is open and triangular shaped, 5 to 7.5 cm (2 to 3 in.) long. The spikelets are stalked, awnless, 1 to 2 cm (3/8 to 3/4 in.) long when flowering, and loosely arranged on delicate paired or spreading branches. Sometimes they are tinged purple.

The vivid green leaves are short and blunt at the tips, shaped like the prow of a small canoe. They are soft and drooping. Long sheaths clasp the stem. The leaves are smooth above and below, with finely serrated edges. Occasionally the leaves are serrated transversely.

The ligule is pointed and silvery. Compared this to Common Meadowgrass Poa pratensis , which has a squared ligule, and Poa trivialis , which has a pointed, but less silvery ligule.

The leaves are smooth above and below, with finely serrated edges. Occasionally the leaves are serrated transversely.

It is in flower all year around except for severe winters. The seeds ripen and are deposited 8 months of the year. The plant grows rapidly from seed, flowering within 6 weeks, seeding and then dying. [5]

Etymology

Poa is derived from the Greek name for a type of fodder grass. [6] Annua is Latin, meaning 'annual' or 'lasting a year'. [6]

Distribution and habitat

It is a common weed of cultivation, known in the Americas as annual bluegrass. [7] It occurs as a common constituent of lawns, where it is also often treated as a weed, and grows on waste ground. Many golf putting greens, including the Oakmont Country Club greens, are annual bluegrass, [8] although many courses have converted to creeping bentgrass (Agrostis stolonifera).

It has appeared on King George Island in the Antarctic South Shetland Islands as an invasive species, [9] as well as on Australia's subantarctic Heard and Macquarie Islands.

Related Research Articles

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<i>Poa pratensis</i> Species of plant

Poa pratensis, commonly known as Kentucky bluegrass, smooth meadow-grass, or common meadow-grass, is a perennial species of grass native to practically all of Europe, North Asia and the mountains of Algeria and Morocco. There is disagreement about its native status in North America, with some sources considering it native and others stating the Spanish Empire brought the seeds of Kentucky bluegrass to the New World in mixtures with other grasses. It is a common and incredibly popular lawn grass in North America with the species being spread over all of the cool, humid parts of the United States. In its native range, Poa pratensis forms a valuable pasture plant, characteristic of well-drained, fertile soil. It is also used for making lawns in parks and gardens and has established itself as a common invasive weed across cool moist temperate climates like the Pacific Northwest and the Northeastern United States. When found on native grasslands in Canada, for example, it is considered an unwelcome exotic plant, and is indicative of a disturbed and degraded landscape.

<i>Poa</i> Genus of flowering plants in the grass family Poaceae

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<i>Elymus repens</i> Species of grass

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<i>Molinia caerulea</i> Species of grass

Molinia caerulea, known by the common name purple moor-grass, is a species of grass that is native to Europe, west Asia, and north Africa. It grows in locations from the lowlands up to 2,300 m (7,546 ft) in the Alps. Like most grasses, it grows best in acid soils, ideally pH values of between 3.5 and 5, however, it can continue to live under more extreme conditions, sometimes to as low as 2. It is common on moist heathland, bogs and moorland throughout Great Britain and Ireland. Introduced populations exist in northeastern and northwestern North America.

A ligule is a thin outgrowth at the junction of leaf and leafstalk of many grasses and sedges. A ligule is also a strap-shaped extension of the corolla, such as that of a ray floret in plants in the daisy family Asteraceae.

<i>Agrostis stolonifera</i> Species of grass

Agrostis stolonifera is a perennial grass species in the family Poaceae. It is widely used as turf for golf courses.

<i>Cynosurus cristatus</i> Species of grass

Cynosurus cristatus, the crested dog's-tail, is a short-lived perennial grass in the family Poaceae, characterised by a seed head that is flat on one side. It typically grows in species rich grassland. It thrives in a variety of soil types but avoids the acid and calcareous extremes of pH, and prefers well drained soils. It may be grown as an ornamental plant.

<i>Poa nemoralis</i> Species of grass in the family Poaceae

Poa nemoralis, the wood bluegrass, is a perennial plant in the family Poaceae. The late-growing grass is fairly nutritious for livestock, which feed on it in the autumn, and it is used as a lawn grass for shady situations.

<i>Poa trivialis</i> Species of grass

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<i>Bromus hordeaceus</i> Species of grass

Bromus hordeaceus, the soft brome, is an annual or biennial species of grass in the grass family (Poaceae). It is also known in North America as bull grass, soft cheat, and soft chess.

<i>Agrostis capillaris</i> Species of grass

Agrostis capillaris, the common bent, colonial bent, or browntop, is a rhizomatous and stoloniferous perennial in the grass family (Poaceae). It is native to Eurasia and has been widely introduced in many parts of the world. Colonial bent grows in moist grasslands and open meadows, and can also be found in agricultural areas, roadsides, and invading disturbed areas.

<i>Bromus sterilis</i> Species of grass

Bromus sterilis is an annual or biennial species of bromegrass known as barren brome, poverty brome, and sterile brome.

<i>Agrostis gigantea</i> Species of grass

Agrostis gigantea, known by its common names black bent and redtop, is a perennial grass of the Agrostis genus.

<i>Poa compressa</i> Species of grass

Poa compressa, the Canada bluegrass or flattened meadow-grass, is a perennial flattened meadow grass, similar to common meadow-grass, Poa pratensis. It is native to Europe but it can be found nearly worldwide as an introduced species. It grows in old wall tops, pavement cracks, dry stony grassland, and many types of wild habitat. It has a flattened stem, 23–30 cm tall, a close one sided panicle of grey green, with purple florets.

<i>Poa infirma</i> Species of grass

Poa infirma is a species of grass known by the common names early meadow-grass and weak bluegrass. It was first described from a specimen found in Colombia, but it is actually an introduced species in the Americas and is native to Europe. It grows in many types of habitat, including disturbed areas. It is very similar to Poa annua, which is probably a daughter species, and it is often mistaken for P. annua unless it is closely examined.

<i>Bromus commutatus</i> Species of grass

Bromus commutatus, the meadow brome, is an annual or biennial species of plant in the grass family Poaceae. In the United States it is known as hairy chess.

British NVC community OV12 is one of the open habitat communities in the British National Vegetation Classification system. It is one of eight arable weed and wasteland communities of fertile loams and clays.

<i>Lolium giganteum</i> Species of grass

Lolium giganteum, giant fescue, is a woodland grass that grows on neutral to base-rich soils, often near streams or other damp places. It is native to Europe and much of Asia and has been introduced to parts of North America.

References

  1. Brummitt, N. (2013). "Annual meadow grass". IUCN Red List of Threatened Species . 2013: e.T168729A1217340. Retrieved 20 February 2022.
  2. Jr, J. M. Vargas; Turgeon, Alfred J. (2003-12-19). Poa Annua: Physiology, Culture, and Control of Annual Bluegrass. John Wiley & Sons. ISBN   978-0-471-47268-1.
  3. Collins pocket guide Grasses, Sedges, Rushes and Ferns. Fitter.R, Fitter.A, Farrer.A. 1995. page 54
  4. Benson, Christopher W.; Sheltra, Matthew R.; Maughan, Peter J.; Jellen, Eric N.; Robbins, Matthew D.; Bushman, B. Shaun; Patterson, Eric L.; Hall, Nathan D.; Huff, David R. (2023-06-26). "Homoeologous evolution of the allotetraploid genome of Poa annua L". BMC Genomics. 24 (1): 350. doi: 10.1186/s12864-023-09456-5 . ISSN   1471-2164. PMC   10291818 . PMID   37365554.
  5. BSBI Description Archived 2011-07-17 at the Wayback Machine retrieved 10 December 2010.
  6. 1 2 Gledhill, David (2008). "The Names of Plants". Cambridge University Press. ISBN   9780521866453 (hardback), ISBN   9780521685535 (paperback). pp 50, 308
  7. Ohlendorf, B.; D. W. Cudney; C. L. Elmore; V. A. Gibeault (April 2003). "Annual Bluegrass Management Guidelines--UC IPM". University of California. Retrieved 2007-09-08.
  8. Dvorchak, Robert (2007-06-13). "Oakmont-inspired Stimpmeter allows USGA to accurately measure speed, consistency of putting surfaces". Pittsburgh Post-Gazette.
  9. Antarctic ecology: Polar invaders, The Economist, Mar 6th 2012