|
''Panicum hemitomon'' is a species of grass known by the common name maidencane. It is native to North America, where it occurs along the southeastern coastline from New Jersey to Texas.〔Godfrey, R. K. and Wooten, J. W. 1979. Aquatic and wetland plants of southeastern United States: monocotyledons.〕 It is also present in South America.〔Walsh, Roberta A. 1994. (''Panicum hemitomon''. ) In: Fire Effects Information System, (). U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory. Retrieved August 1, 2012.〕 This plant is a rhizomatous perennial grass with stems reaching up to 2 meters in height. It is aquatic or semi-aquatic, growing in water or wet soils. It spreads via its rhizome to form large colonies.〔(''Panicum hemitomon''. ) Grass Manual Treatment. Retrieved August 1, 2012.〕 The canelike roots are filled with air and form a mass up to 46 centimeters wide. The stems may be erect or spreading; if nodes on the stem contact moist substrate they will root. Stems that break off and float away may root where they land. There are fertile and sterile stems.〔 The leaves are up to 35 centimeters long by 1.5 wide and have tapering tips. The inflorescence is a panicle with upright branches.〔 This species is a common grass in coastal wetlands. It is only found in freshwater, not sea water or brackish water. It can be found in many types of freshwater wetlands as well as in ditches and disturbed or cultivated areas.〔Chabreck, R. H. 1972. Vegetation, water and soil characteristics of the Louisiana coastal region. Louisiana State Univ. Agric. Exp. Stn.〕 It is less sensitive to grazing than many associated species, but growth is reduced by competition from neighboring plants.〔Geho, E.M., D. Campbell and P. A. Keddy. 2007. Quantifying ecological filters: the relative impact of herbivory, neighbours, and sediment on an oligohaline marsh. Oikos 116: 1006-1016.〕 It is common in the Everglades and other regions in Florida.〔Loveless, C. M. 1959. A study of the vegetation in the Florida everglades. Ecology 40: 1–9.〕 It may form large monotypic stands which are rooted or floating free to form a floating marsh. It forms its most dense stands on the drier sites in wet habitats. It can tolerate several months of flooding. The rhizome network helps to stabilize soil and prevent erosion.〔 Some biologists therefore refer to it as a keystone species〔Mayence, C.E. and M.W. Hester. 2009. Growth and allocation by a keystone wetland plant, ''Panicum hemitomon'', and implications for managing and rehabilitating coastal freshwater marshes, Louisiana, USA. Wetlands Ecology and Management 18: 149-63.〕 This grass sprouts from the rhizome in the winter and grows over the course of the year. It is most dense in summer and fall. The aboveground parts die and break off, forming floating mats. Then the rhizome becomes dormant.〔 Maidencane is good for cattle forage, and there are maidencane-dominated marshes in Florida which are used for cattle grazing. It can be used as hay. It is also eaten by deer and utilized by the Florida panther, which lives in the marshes. The American alligator also lives in maidencane wetlands. Many other animals are found in these habitat types.〔 The plant is considered a weed in some places, such as cultivated crop fields. It is also considered a nuisance species when it becomes very dense. It may compete with food plants for waterfowl. Controlled burns are sometimes initiated to thin the plant.〔 ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Panicum hemitomon」の詳細全文を読む スポンサード リンク
|