''Alopecurus geniculatus'' is a species of

grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...

known by the common name water foxtail or marsh foxtail. It is native to much of

Eurasia Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents d ...

and introduced into

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

, and

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

. It grows in moist areas. ''Alopecurus geniculatus'' is a

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

grass forming bunches of erect stems up to about 60 cm (24 inches) in height. The leaves are up 12 cm (5 inches) in length. The pale green to purplish

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is a dense

panicle In botany, a panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a p ...

up to 6 or 7 cm long which blooms in dusty yellow-orange

anthers The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filamen ...

. reproduces sexually by seeds and can reproduce vegetatively by rooting at stem nodes. In Europe, it can be affected by a fungus, known as 'Foxtail Smut', ''

Urocystis alopecuri ''Urocystis alopecuri'' is a fungal plant pathogen in the family Urocystidiaceae. Known as 'Foxtail Smut'. It is found on ''Alopecurus'' species; such as ''Alopecurus aequalis'', ''Alopecurus arundinaceus'', ''Alopecurus geniculatus'', ''Alopecu ...

''.

Environmental conservation

''Alopecurus geniculatus'' is a component of

purple moor grass and rush pastures Purple moor grass and rush pastures is a type of Biodiversity Action Plan habitat in the UK. It occurs on poorly drained neutral and acidic soils of the lowlands and upland fringe. It is found in the southwest of England, especially in Devon. ...

a type of Biodiversity Action Plan habitat in the UK. It occurs on poorly drained neutral and acidic soils of the lowlands and upland fringe.

Nonindigenous spread

The grass has spread significantly in the United States since it was first introduced.

Hybrid

''Alopecurus geniculatus'' is known to hybridize with other members of the ''Alopecurus'' genus. ''Alopecurus x haussknechtianus'' is a hybrid between ''A. geniculatus'' and ''A. aequalis'', ''Alopecurus x brachystylus'' is a hybrid between ''A. geniculatus'' and ''A. pratensis'', ''Alopecurus x plettkei'' is s hybrid between ''A. geniculatus'' and '' A. bulbosus'' (Botanical Society of Britain and Ireland 2016).

References

External links

Jepson Manual TreatmentUnited States Department of Agriculture Plants ProfileGrass Manual TreatmentCalphotos Photo gallery, University of California
geniculatus Bunchgrasses of Asia Bunchgrasses of Europe Plants described in 1753 Taxa named by Carl Linnaeus {{Pooideae-stub