Imperata cylindrica
Imperata brevifolia
bladygrass, cogon grass
California satintail, satintail
(10)30-95(217) cm.
51-129 cm.
5.7-22.3(52) cm, narrowly cylindrical;
lower branches 1-3.2(7) cm, appressed.
16-34 cm, dense;
lower branches 2-5 cm, divergent.
0.2-3.5 mm;
blades to 150 cm long, (1)3-11(28) mm wide, linear-lanceolate, bases narrowed to the broad midrib, often with hairs on the margins.
0.7-2.9 mm;
blades 7-14 mm wide, linear to lanceolate, abaxial surfaces smooth, adaxial surfaces sometimes densely pilose basally, otherwise scabrous.
hairs 9-16 mm;
glumes 2.6-5.5 mm;
lower lemmas 1.4-4.5 mm;
upper lemmas (0.7)1.3-2.3(3.4) mm;
stamens 2, filaments not dilated at the base;
anthers (1.5)2.2-4.2 mm, orange to brown;
styles 0.5-3.4 mm;
stigmas 2.8-5.2(8.3) mm, purple to brown.
hairs 8-12 mm;
glumes 2.7-4.1 mm;
lower lemmas 2.5-3.9 mm, membranous, glumelike;
upper lemmas 1.4-2.4 mm, completely surrounding the ovary;
stamens 1, filaments dilated at the base;
anthers 1.3-2.3 mm, yellow to orange;
styles 0.9-2.4 mm;
stigmas 2.1-4 mm, purple to brown.
= 20, 40, 60.
= 20.
Imperata cylindrica
Imperata brevifolia
Imperata cylindrica is the most variable species in the genus. Several varieties have been recognized but, although there are statistically significant differences between plants from different regions, identification to variety without knowledge of a plant's geographic origin is risky. All North American plants examined have had 2n = 20.
Imperata cylindrica is one of the world's 10 worst weeds, and is listed as a noxious weed by the U.S. Department of Agriculture. It was introduced to Alabama by 1912, and has spread considerably through the southeastern United States since then. The cultivar 'Red Baron' is diminutive and non-weedy, but individual shoots may revert to the aggressive form. Such reversion is particularly common in plants grown from tissue culture.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Once known from wet or moist sites in the southwestern deserts from southern California, Nevada, and Utah to western Texas, Imperata brevifolia is currently known only from populations in Grand Canyon National Park. It was last collected outside the park in the early 1970s at a site that is now under Lake Powell. Most collections were made before 1945, in sites that are now used for housing or agriculture.
Imperata brevifolia was listed as a noxious weed by the state of California. The reason for the listing is not clear; it may have stemmed from confusion of this native species with one of the introduced weedy species.
In September 2003, G.F. Hrusa succeeded in persuading the California authorities that Imperata brevifolia should be taken off the state's noxious weed list. Endangered species status is now being sought.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Flora NW
LA Plants
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
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