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Reed Canary Grass
Grass Family
Reed canary grass (Phalaris arundinacea) is a perennial non-native grass
species that is aggressively invading mid-elevation meadows in Sequoia and
Kings Canyon National Parks. It is considered native to some parts of
California, but not to Sequoia and Kings Canyon National Parks. It is highly
probable that these local populations are also hybridized with European
strains of reed canary grass. Reed canary grass is a source of particular
concern for park managers because it spreads rapidly,
can alter stream and meadow hydrology, is very tenacious, and
tends to exclude all other vegetation.
Identification
Reed canary grass is perennial and grows from tough rootstocks. It attains
heights of up to 1.5 meters (4 feet), and produces cylindrical flower heads.
These flower heads are 7 to 40 centimeters (2.8-16 inches) tall,
and the flower clusters at the bottom of each head are often irregularly spaced.
Reed canary grass is restricted to moist areas such as meadows and stream
banks and is only known from middle elevations in Sequoia and Kings Canyon
National Parks. These populations characteristically form dense stands,
pushing out all other vegetation.
Look-Alikes
There are numerous grasses, sedges, and related plants that can appear
similar to reed canary grass. The two most distinguishing features of reed
canary grass are its cylindrical flower heads, and its habit of forming
dense, exclusive colonies in mid-elevation wetlands.
Natural History
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Reed canary grass excludes nearly all plant species in a mid-elevation meadow
near Grant Grove in Kings Canyon National Park.
Inset photo: mature flowering heads of reed canary grass.
Large photo © NPS by Athena Demetry;
inset photo (modified) © Wisconsin Department of Natural Resources.
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While reed canary grass is known to have fairly shallow roots, it grows
extremely well on moist soils and soaks up large amounts of soil nutrients.
It can alter the water balance in wetlands by evaporating and transpiring
large quantities of soil moisture and by clogging ditches and stream courses.
Reed canary grass is capable of sprouting roots directly from its stems;
this has implications for how the plant must be disposed of after it has been
cut or uprooted (i.e. it cannot be mulched under).
Management
Reed canary grass is present only in moist meadows and riparian sites in
Grant Grove and in one small patch in Lodgepole.
In 2002 park resource management personnel began removing small
satellite populations. Ultimately the NPS intends to eradicate this species
or contain it to the Wilsonia area.
After attempting removal of this plant by hand, the
park determined that hand digging is too disruptive to
fragile meadow soils. In 2002, the park began managing
sites on meadow perimeters using a combination of hand
removal and approved glyphosate herbicides. The stems
were cut shortly before flowering and the grass was allowed
to resprout. Three weeks after cutting, the resprouts
were treated with herbicide. These
targeted spot treatments treatment have been
very successful, producing a 90% reduction in reed
canary grass cover.
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