''Achnatherum richardsonii'' 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 names Richardson's needlegrass, spreading needlegrass, and Canada mountain-ricegrass. It is native to northwestern North America, where it is distributed from

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

''Achnatherum richardsonii''.
USDA Plants Profile. and

Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...

through the western Canadian provinces south to

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

.Esser, Lora L. 1992
''Achnatherum richardsonii''.
In: Fire Effects Information System, nline U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory. This is a tufted perennial

bunchgrass Tussock grasses or bunch grasses are a group of grass species in the family Poaceae. They usually grow as singular plants in clumps, tufts, hummocks, or bunches, rather than forming a sod or lawn, in meadows, grasslands, and prairies. As perennia ...

growing up to a meter tall. The

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 open with spreading branches. The spikelet has a twisted awn up to 2.5 centimeters in length.''Achnatherum richardsonii''.
Grass Manual Treatment. This grass grows in several habitat types, including

grassland A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceo ...

meadow A meadow ( ) is an open habitat or field, vegetated by grasses, herbs, and other non- woody plants. Trees or shrubs may sparsely populate meadows, as long as they maintain an open character. Meadows can occur naturally under favourable con ...

s, and

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. ''World Flora Online'' accepts 134 species-rank taxa (119 species and 15 nothospecies) of pines as cu ...

forests. It can be found on

moraine A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a gla ...

s, plains, and mountain slopes. It is a dominant or codominant grass species in some areas, such as the western Canadian grasslands and the climax plant communities of Glacier National Park. Plants associated with it include Canada bluegrass (''Poa compressa''), prairie Junegrass (''Koeleria cristata''), rough fescue (''Festuca altaica''), Idaho fescue (''F. idahoensis''), bearded wheatgrass (''Elymus caninus''), western needlegrass (''Achnatherum occidentalis''), timber danthonia (''Danthonia intermedia''), tufted hairgrass (''Deschampsia cespitosa''),

sedges The Cyperaceae () are a family of graminoid (grass-like), monocotyledonous flowering plants known as sedges. The family is large; botanists have described some 5,500 known species in about 90 generathe largest being the "true sedges" (genu ...

(''Carex'' spp.), shrubby cinquefoil (''Potentilla fruticosa''), bearberry (''Arctostaphylos uva-ursi''), timothy (''Phleum pratense''), common yarrow (''Achillea millefolium''), prairiesmoke avens (''Geum triflorum''), northern bedstraw (''Galium boreale''), Hood's phlox (''Phlox hoodii''), and bluebell (''Campanula rotundifolia''). This grass is a common food source for livestock and wildlife such as elk and

bighorn sheep The bighorn sheep (''Ovis canadensis'') is a species of Ovis, sheep native to North America. It is named for its large Horn (anatomy), horns. A pair of horns may weigh up to ; the sheep typically weigh up to . Recent genetic testing indicates th ...

on the

Great Plains The Great Plains is a broad expanse of plain, flatland in North America. The region stretches east of the Rocky Mountains, much of it covered in prairie, steppe, and grassland. They are the western part of the Interior Plains, which include th ...

. It is preferable when young because as it matures, the fruits become hard and sharp.

References

External links

The Nature Conservancy
{{Taxonbar, from=Q4673858 richardsonii Bunchgrasses of North America Grasses of Canada Grasses of the United States Flora of the Northwestern United States Flora of Western Canada