Orchard Grass

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Species Description and Current Range
Orchard Grass is a long-lived, cool-season bunchgrass characterized by a distinctively shaped seed head, or panicle.
The shape of the panicle earned this species the name ‘cocksfoot’ in Canada, Europe, New Zealand, and Australia.
The panicle is strongly tufted, clustered on one side of the branch, and reaches 3-15 cm in height. The selection of
the genus name Dactylis, which derives from the Greek word ‘dactulos’ meaning a finger, is attributed to the stiff
branches of the panicle. Orchard Grass typically reaches a height of 50-120 cm. The base of the leaf enclosing the
stem is compressed, giving it a flattened appearance that is diagnostic for identification. The leaves are 2-12 mm
wide and typically 10-40 cm long, but can reach 1 m in length. The lower leaf surface is not shiny and has a distinct
center ridge. Leaves vary in color depending on variety and soil conditions, but are typically green to blue-green.
Orchard Grass occurs throughout the US and north into southern Canadian provinces. It is well adapted to many
eastern states as well as to moist or irrigated areas of the west. Vegetation communities that Orchard Grass is
particularly suited to in the PNW include Sagebrush, Ponderosa Pine, Douglas Fir, Aspen, and OR White Oak (also
called Garry Oak) ecosystems. OR White Oak/Orchard Grass communities have been described in the Umpqua
River valley and the bald hills oak woodlands of coastal northern CA. It is also commonly found along roadsides
and in pastures, meadows and waste areas.
Impacts to Communities and Native Species
Orchard Grass is quite competitive under favorable conditions, such as when ample nutrients and moisture are
available. However, it is not considered invasive in most areas. In fact, it is a favored forage grass and consequently
animals control its spread in areas with intensive grazing pressure. Where conditions are favorable for growth, it can
become a noxious weed because it is long-lived and, once established, can dominate a community. This is the case
in the Garry Oak (Quercus garryana) ecosystem in BC, where Orchard Grass is considered one of the worst exotic
species threatening this unique ecosystem. Non-native grasses comprise up to 30 percent of the vegetation in Garry
Oak ecosystems. Non-native grasses compete aggressively for nutrients and water and form a dense litter layer that
blocks light and fosters high-intensity fires. Furthermore, Orchard Grass alters the soil nutrient regime by adding
nitrogen from decaying grass litter.
Control Methods and Management
Mechanical control methods have been used on Orchard Grass with limited success. Repeated mowing may
stimulate shoot growth and Orchard Grass may become a problem in lawns. Since it does not aggressively spread
vegetatively, manually pulling out young plants can be effective for small areas if it is completed in early summer
before seeds set. In some locales, Orchard Grass is reported to decline after repeated summer burns, while in other
areas it reportedly persists after a burn. Numerous herbicides are effective on Orchard Grass; however, they are not
specific to it and therefore may not be practical where Orchard Grass persists in a landscape with native species. No
known biological control exists.
Life History and Species Overview
Orchard Grass is a favored forage crop producing high-yield and high-quality forage that is palatable to all classes of
livestock. It is also one of the earliest grass species to grow in spring, exhibiting prodigious growth during cool
conditions. Strong summer growth can also occur under favorable conditions because it is so deeply rooted. It is
highly tolerant of shade, which probably earned it the name ‘orchard’ grass, but it also grows well in open areas.
Orchard Grass prefers well-drained soils, but tolerates moderately poor drainage as well as drought conditions,
persisting in areas with as little as 250 mm of annual rainfall. Its ability to withstand drought is a result of its
extensive root system. In dry areas, it may lay dormant during the summer and in the fall, add new growth and
possibly flower again. It does not grow well on areas of high water tables or on saline soils. It produces a dense sod
in the upper 8 cm of soil but some roots extend 46 cm or more below the surface.
Orchard Grass can reproduce two ways: sexually by seed and asexually by new shoot formation from underground
stems and roots. Its seed remains viable for only 2-3 years. This trait has likely prevented this species from
becoming invasive in most areas. Germination often occurs in fall and is largely controlled by moisture availability;
therefore, Orchard Grass does not tend to build up seed banks in the soil. Seeds can collect on animal hair and
disperse long distances.
Orchard Grass is also used for erosion control and upland wildlife and conservation plantings. Its value for erosion
control stems from its tendency to form highly dense root networks. It is also used as a cover crop under orchards
and in other disturbed areas, such as after a prescribed and controlled burn. It is also highly palatable for elk and
deer, and the persistent, green basal rosette is utilized for winter forage.
History of Invasiveness
Native to western and central Europe, Orchard Grass was introduced to the eastern US around 1760. In the 1830s, its
forage value was recognized by settlers in VA and its use spread across the US. Orchard Grass has been used in the
PNW since the early 1900s as a hay, pasture, and silage crop.
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