Comprehensive DescriptionRead full entry
Thin paspalum is a short-lived, warm-season, tufted, perennial grass that grows 2 ½ to 3 feet tall. The base of the plant is knotty and has short rhizomes. It is a member of the Paniceae tribe of Poaceae, the grass family (Hitchcock, 1971). There are four varieties of Paspalum setaceum: setaceum, stramineum, muhlenbergii, and ciliatifolium. Not all plant authorities recognize these varieties.
Paspalum setaceum var. setaceum (previously P. debile) is identified by some plant authorities as thin paspalum. Others recognize the varieties, but consider thin paspalum to be Paspalum setaceum, a separate entity from the other varieties. Still others see thin paspalum as the whole Paspalum setaceum complex, and do not recognize the individual varieties at all. The varieties will be discussed herein because the most recent authority recognizes them.
The variety setaceum (previously P. debile, which Gould (1975) calls thin paspalum) can be differentiated from the other varieties as having narrower leaf blades, shorter spikelets, and gray-green herbage.
The variety stramineum (previously P. stramineum) is distinguished from the other varieties by narrower leaf blades and yellow-green foliage.
The variety muhlenbergii (previously P. muhlenbergii and P. pubescens) has light to dark green, pilose leaf blades and is distinguished by a conspicuous midvein on the lower floret.
Finally, the variety ciliatifolium (previously P. ciliatifolium and P. propinquum) is recognized by its glabrous dark green to purplish herbage. It is commonly called fringeleaf paspalum.
It is important to note that populations of widely variable, but intergrading plant types are included in the Paspalum setaceum complex.