Dichanthelium sphaerocarpon

Dichanthelium sphaerocarpon
Photo by Guy Anglin, Atlas of Florida Vascular Plants
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta - Flowering plants
Class:	Liliopsida – Monocotyledons
Order:	Cyperales
Family:	Poaceae ⁄ Gramineae
Genus:	Dichanthelium
Species:	D. sphaerocarpon
Binomial name
Dichanthelium sphaerocarpon (Elliott) Gould
Natural range of Dichanthelium sphaerocarpon from USDA NRCS Plants Database.

Common name: roundseed panicgrass

Synonym: Panicum sphaerocarpon Elliott

Description

Dichanthelium sphaerocarpon is a perennial graminoid.

Generally, for the Dichanthelium genus, they have "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 an 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)." - Radford et al 1964.

Specifically, for the D. sphaerocarpon species, they are "perennial with distinct basal rosettes; branching, when present, from nodes above basal rosette. Leaves basal and cauline, vernal and autumnal. Culms 1,5-5 dm tall, nodes upwardly bearded, internodes glabrous. Blades to 9.5 cm long, 2-20 mm wide, glabrous or slightly scaberulous on both surfaces, margins white, scaberulous, bases cordate, ciliate; sheaths glabrous, margins papillose-ciliate; ligules obsolete or ciliate and 0.1-0.5 mm long. Panicle 4-13 cm long, 2-9 cm broad, 2/3 or more as borad as long; rachis glabrous, branches spreading-ascending, glabrous. Spikelets subglobose, 1.4-1.6 mm long; pedicels glabrous. First glume glabrous, truncate, acute, or obtuse, 0.3-0.8 mm long, 2nd glume and sterile lemma puberulent, obtuse, 1.4-1.6 mm long; fertile lemma and palea 1.3-1.5 mm long. Grain 1 mm long. yellowish or purplish, broadly ellipsoid or subglobose." - Radford et al 1964.

Ecology

Habitat

Dichanthelium sphaerocarpon occurs in a variety of natural and disturbed communities. It is abundant in barrens habitats, but also occurs in pine-oak flatwoods and woodlands, mixed hardwood floodplains, pine forests, cabbage palm hammocks, and on loessial banks, the edges of open brackish marshes, and sand dunes (FSU Herbarium). It is also able to grow in disturbed areas, especially in higher light levels (FSU Herbarium). D. sphaerocarpon has been found in power line corridors, clear-cuts, roadsides, ditches, firebreaks, and old fields (FSU Herbarium). This species seems to prefer sandy or loamy soils, but can tolerate a range of moisture levels, from dry to wet (FSU Herbarium).

Associated species include Carex, Juncus, Sarracenia, Taxodium (FSU Herbarium).

Phenology

Flowering and fruiting has been observed in Florida in February through November (FSU Herbarium).

Fire ecology

It increased from being absent to 19 plots within the span of six years after an early dormant-season fire in 1989 at Gibbons Creek Barrens.

References and notes

Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: June 2014. Collectors: Loran C. Anderson, T. MacClendon, K. MacClendon, Cecil R Slaughter, Lisa Keppner, Ed Keppner, R. Kral, Richard Carter, Charles M. Allen, Sidney McDaniel, Randy Haynes, Paul L. Hallister, Ken Rogers, Louise Rogers, Lloyd H. Shinners, Duane Isely, S L Welsh, Dwight Isely, Bayard Long, John W. Thieret, D J Banks, Fred B Jones, A. E. Radford, R. L. Wilbur, James D. Ray, Jr., Robert F. Thorne, Bob Brown, W. T. Batson Jr., H. L. Blomquist, R.K. Godfrey, P. L. Redfearn, H. Kurz, Bruce Hansen, JoAnn Hansen, Gil Nelson, Angus Gholson, Chris Cooksey, Kevin Oakes, Richard R. Clinebell II, J. M. Kane, C. Nelson, A. Clebsch, Annie Schmidt, A. Johnson, and M. Jenkins. States and Counties: Alabama: Geneva, Houston, Lee, and Monroe. Arkansas: Franklin and St. Francis. Florida: Bay, Calhoun, Collier, Escambia, Flagler, Franklin, Gulf, Holmes, Jackson, Leon, Liberty, Taylor, Wakulla, and Washington. Georgia: Baker, Dougherty, Grady, and Thomas. Kentucky: Lyon. Louisiana: Allen, Caldwell, Jackson, Ouachita, St Mary, and Union. Mississippi: Holmes, Jones, Lowndes, and Pearl River. North Carolina: Beaufort, Brunswick, Craven, and Granville. New Jersey: Gloucester. Tennessee: Putnam. Texas: Freestone, Nueces, San Augustine, and Van Zandt. Virginia: Princess Anne and Prince George. Other Countries: Honduras.

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. 142-158. Print.