Panicum virgatum
| Panicum virgatum | |
|---|---|
| |
| Photo by James H. Miller & Ted Bodner, Southern Weed Science Society, Bugwood.org | |
| Scientific classification | |
| Kingdom: | Plantae |
| Division: | Tracheophyta- Vascular plants |
| Class: | Lilianae - Monocotyledons |
| Order: | Poales |
| Family: | Poaceae |
| Genus: | Panicum |
| Species: | P. virgatum |
| Binomial name | |
| Panicum virgatum L. | |
| |
| Natural range of Panicum virgatum from USDA NRCS Plants Database. | |
Common names: Switchgrass[1], Blunt panic grass, Tufted switchgrass
Contents
Taxonomic notes
Synonyms: none.[1]
Varieties: Panicum virgatum Linnaeus var. cubense Grisebach; Panicum virgatum Linnaeus var. spissum Linder; Panicum virgatum Linnaeus var. virgatum.[1]
Description
"Spikelets usually in panicles, round or nearly so in cross section, 2-flowered, terminal fertile, basal sterile, neutral or staminate. First glume usually present, 2nd glume and sterile lemma similar; fertile lemma and palea indurate without hyaline margins. Taxonomically our most difficult and least understood genus of grasses, more than 100 species and varieties are ascribed to the Carolinas by some authors. Note general descriptions for species groups (e.g., 1-4, 5-8, 9-13, and 26-62)."[2]
"Elongate, rhizomatous perennial; culms 5-15 dm tall. Blades to 5 dm long, 1.5-8 mm wide, sparsely pilose above basally; sheaths occasionally pubescent, margins occasionally densely ciliate; ligules ciliate or lacerate, 1.5 mm long. Panicle open, 12-50 cm long, 6-20 cm broad. Spikelets 2.8-4.2 mm long. Frist glume 5-9 nerved, acute to keeled-cuspidate, 1.4-3.0 mm long, 2nd glume and sterile lemma 7-9 nerved, acute to cuspidate, 2.8-4.2 mm long, sterile palea2-2.6 mm long; fertile lemma 2-2.6 mm long. Grain grayish, 1-2 mm long."[2]
The spikelets of var. cubense are 2.8-3.5 mm long, and the first glume (blunt-) acute, ½-⅔× as long as the spikelet. The beak of the sterile lemma exceeds the fertile lemma by 0.2-0.5 mm. Adversely, the spikelets of the other varieties are 3.2-5 mm long, where the first glume is acuminate, ⅗-¾x as long as the spikelet. The beak of sterile lemma exceeding fertile lemma by 0.6-1.3 mm. Var. spissum can be distinguished by its short, densely-interlocking rhizomes and subascending, basal culms. It also grows densely clumped. Var. virgatum the rhizomes are elongate, the culms are horizontally divergent, and it grows loosley-clumped.[1]
Distribution
Var. cubense is found in the Coastal Plain from Massachusetts to Florida, and west to Missouri and Michigan. It also grows in the West Indies. Var. spissum grows from East Canada to Pennsylvania, Maryland, and Deleware. Var. virgatum has the broadest range, from southwest Quebec to Florida and Texas, then west to Nevada. Its range also extends to Bermuda, Central America, and South America.[1]
Ecology
Habitat
Var. cubense frequents wet to dry sandy pinelands. Var. spissum grows in gravelly or sandy fresh to brackish shores and swamps. Var. virgatum is found in dry or wet sandy soils of pinelands, fresh and brackish marshes, and shores.[1] This variety Is also frequent and abundant in the Calcareous Savannas and Upper Panhandle Savannas community types as described in Carr et al. (2010).[3]
The species responds negatively to soil disturbance by agriculture in Southwest Georgia.[4]
Phenology
P. virgatum flowers from Jun through October.[1]
Seed dispersal
This species is thought to be dispersed by gravity.[5]
Conservation and management
Cultivation and restoration
Photo Gallery
References and notes
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Weakley, A.S. 2015. Flora of the southern and mid-atlantic states. Working Draft of 21 May 2015. University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
- ↑ 2.0 2.1 Radford, Albert E., Harry E. Ahles, and C. Ritchie Bell. Manual of the Vascular Flora of the Carolinas. 1964, 1968. The University of North Carolina Press. 145. Print.
- ↑ Carr, S.C., K.M. Robertson, and R.K. Peet. 2010. A vegetation classification of fire-dependent pinelands of Florida. Castanea 75:153-189.
- ↑ Kirkman, L.K., K.L. Coffey, R.J. Mitchell, and E.B. Moser. Ground Cover Recovery Patterns and Life-History Traits: Implications for Restoration Obstacles and Opportunities in a Species-Rich Savanna. (2004). Journal of Ecology 92(3):409-421.
- ↑ Kirkman, L. Katherine. Unpublished database of seed dispersal mode of plants found in Coastal Plain longleaf pine-grasslands of the Jones Ecological Research Center, Georgia.
