white cutgrass (whitegrass)
Leersia virginica Willd.

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planthabithabitrhizomeinflorescencespikeletillustration

White cutgrass can be found in moist places in wooded areas or streams throughout the eastern half of the United States. It is found throughout the state of Iowa in moist alluvial woods, wooded ravines, and around lakes or ponds. White cutgrass, which flowers from July to October, is easily distinguished from rice cutgrass (Leersia oryzoides) by its smooth (or nearly smooth) leaf sheaths, flowering heads with solitary lower branches in the flowering heads, smaller and more strongly overlapping spikelets, and short rhizomes with strongly overlapping scales. Rice cutgrass, in contrast, has leaf sheaths round enough to cause painful scratches, flowering heads with two or more branches at the lowermost nodes, larger and barely overlapping spikelets, and more elongated rhizomes with the scales usually not overlapping.

Etymology: Leersia is named for Johann Daniel Leers (1727-1774), a German botanist and pharmacist; from the Latin, virginica = of or from Virginia (eastern), referring to the locality of the original collections of this species.

 

Plants with short, scaly rhizomes, the scales overlapping, giving the rhizomes a braided appearance. Culms (20-) 40-100 cm, branching and sometimes rooting at the nodes, more or less glabrous, the nodes hairy. Leaves with the sheaths smooth to slightly rough; ligules 1-2 mm long; blades (5-) 6-17 cm long, (3-) 6-11 mm wide, droopy, smooth to minutely pubescent above and below, sometimes densely short-long hairy beneath, with long, stiff pubescence along the margin. Flowering heads 9-18 cm long, usually emerging completely from the sheath below, the base sometimes remaining hidden; branches 4-10 cm long, spreading, 1 per node, naked on the lower 1/3. Spikelets 3-4 mm long, 1-1.4 mm wide, oblong, barely overlapping, more or less appressed. Lemmas ciliate to nearly smooth on the keel and margins, smooth to short-pubescent on the body; palea ciliate on the keel; anthers 2. Chromosome number n = 24.

 

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