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GRASSES OF THE COLUMBIA BASIN OF BRITISH COLUMBIA Heather Stewart, Richard Hebda Major Groups of Grasses Table of Contents Glossary Panicum Panic Grass Panic grasses are part of a large, mainly tropical and subtropical genus. Only three species occur in the Columbia Basin of British Columbia: Panicum capillare, Panicum occidentale and Panicum oligosanthes var. scribnerianum. The word panicum is Latin for millet -- a common name used for several Panicum species. An interesting feature of the Panicum species is the variation in appearance as the season progresses. Initially the flowerhead is extended well out of the sheath; but as the season progresses the later emerging flowerheads do not extend as far out of the sheath, and in some cases the sheath encloses half the flowerhead. Panicum   1a. Plants annual; lemma tip pointed........................................................................Panicum capillare   1b. Plants perennial; lemma tip rounded or blunt..................................................................................2   2a. Spikelets 3.2 mm. long.................................................Panicum oligosanthes var. scribnerianum   2b. Spikelets rarely 2 mm. long............................................................................ Panicum occidentale   Panicum capillare L. Common Witchgrass Plant: Panicum capillare is a native species that grows to 20-70 cm tall. It is an annual that appears to be bent at the base. The flowerhead is open and repeatedly branched, with single, small spikelets at the end of each branch. Leaves and Stem: The stem and open sheaths have 2-4-mm-long hairs spread abundantly throughout. The ligules are 1.5-2 mm long and consist entirely of hairs. Flat leaf blades are 5-12 mm wide. There are no auricles. Flowerhead and Flowers: The open flowerhead has widely separated branches, and the length is 10-30 cm long. The first glume is three-nerved and half as long as the spikelet. The pointed second glume is seven-nerved and as long as the sterile lemma, which is nine-nerved: both exceeding the fertile lemma. The first lemma is sterile and the second lemma is hardened and fertile. Habitat: Common Witchgrass occupies moist to dry roadsides, railways embankments, gravelly slopes and fields in lowland to montane zones. In the Columbia Basin it occurs at Midway, Kokanee Glacier Park, Trail, Hidden Lake and Mud Lake. Similar Species: Common Witchgrass differs from other Panicum species in that the first glume is half as long as the spikelet, and the tip of the glume is pointed. Panicum occidentale Scribn. Dicanthelium lanuginosum (Elliot) Panicum pacificum Hitch. & Chase Panicum thermale Boland Western Witchgrass Plant: Panicum occidentale is a native species that grows to 15-40 cm tall. It is a tufted, velvety, greyish-green perennial with an open, branching flowerhead. Leaves and Stem: The open sheaths are densely hairy and there are no auricles. The ligule is 3-4 mm long and consists of a ring of hairs. The flat, firm leaves are 5-10 mm wide and have a hairy lower surface. The upper leaves are slightly larger than the basal leaves. Flowerhead and Flowers: The flowerhead is open, 3-9 cm long and almost as wide as it is long. Elliptic or oblong spikelets with short hairs contain two flowers in each spikelet. The spikelets are rarely 2 mm long. The glumes are much shorter than the first flower. The lower flower is sterile whereas the upper flower is fertile and the lemma hardened. The sterile lemma and the second glume are both rounded at the tip. Habitat: Western Witchgrass grows on moist to dry shores, beaches, open woods, meadows and bogs in the lowland to montane zones. In the Columbia Basin it occurs at Castlegar, Christina Lake, Wasa Lake, Fairmont Hotsprings, Windermere Lake, Canal Flats, Kootenay Lake and Hahas Lake. Similar Species: Few-flowered Witchgrass (P. oligosanthes) resembles Western Witchgrass, but prefers drier habitats and has shorter ligules, longer spikelets and fewer branches. Western Witchgrass is variable in the west, and a complete description of the complex in western North America is contained in Hitchcock et al. (1969). Panicum oligosanthes Schult. var. scribnerianum (Nash) Fern. Dichanthelium oligosanthes (Schult.) Gould Few-flowered Witchgrass Plant: Panicum oligosanthes is a native species that grows to 15-50 cm tall. It is a hairy perennial with an open, but very short, flowerhead. Leaves and Stem: The open sheaths are hairy and there are no auricles. Ligules stand about 1.5 mm high. The upper leaf blades are larger than the basal leaf blades, averaging 5-15 mm wide. Flowerhead and Flowers: The flowerhead is open, 3-8 cm long and contains hairy spikelets that are 3.2 mm long. The first glume is about 1.5 mm long and forms a hardened cuplike base for the rest of the spikelet. The second glume and the sterile lemma are rounded at the tip and barely exceed the fertile flower. Habitat: Few-flowered Witchgrass grows on dry, open, sandy flats, gravelly knolls and rocky bluffs in lowland to montane zones. In the Columbia Basin Few-flowered Witchgrass occurs at Cascade, Trail, and Grand Forks. Similar Species: Few-flowered Witchgrass resembles Western Witchgrass, but prefers drier habitats, and it has shorter ligules, longer spikelets and fewer branches. Both species have dense, short hairs over the second glume and the sterile lemma. Both species also have basal leaves that are distinctly different from those along the stem.

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