rice cutgrass (cutgrass)
Leersia oryzoides (L.) Sw.

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habithabitinflorescenceliguleinflorescencespikeletillustration

Rice cutgrass is usually found growing in wet soils near bodies of water, but may be aquatic. It is widespread from southern Canada to the southern United States. Rice cutgrass is found throughout the state of Iowa on wet banks of lakes and ditches and in swamps, and flowers from late June to almost October. This is the most common species of cutgrass in the state, although it does not occur in the Loess Hills, which is not surprising given the well-drained soil there. Rice cutgrass is readily identified by its very rough leaf sheaths and blade edges (rough enough to cause scratches), the flowering heads with two or more branches at each of the lowest nodes, the barely overlapping spikelets, and, if you have made the effort to dig it up, the more or less elongated rhizomes with scales that do not overlap much if at all. White cutgrass (Leersia virginica), has a more delicate appearance, with nearly smooth sheaths, flowering heads with only one branch at the each of the lowermost nodes, smaller and more strongly overlapping spikelets, and short, scaly rhizomes.

Etymology: Leersia is named for Johann Daniel Leers (1727-1774), a German botanist and pharmacist; oryzoides is from the Latin oryza for having the form of rice, or resembling rice, referring to the appearance of the spikelets.

 

Plants with long, scaly rhizomes, the scales not overlapping. Culms 70-130 cm, branching, reclining at the base but with the tip ascending, sprawling, rooting at the nodes but the terminal portion erect. Leaves with the sheaths very rough; ligules 1-2 mm long; blades (12-) 19-30 cm long, 6-11 mm wide, spreading to slightly ascending, usually rough above and below. Flowering heads 9-23 cm long, terminal or axillary, either completely emerging from the sheath below, or the base remaining hidden within it; branches usually 2 or more at the lowest nodes, spreading, the lower 1/3 naked. Spikelets 4-5.2 mm long, 1.3-1.8 mm wide, elliptic, overlapping. Lemma usually ciliate on the keel, smooth to short pubescent elsewhere; palea ciliate on the keel; anthers 3. Chromosome number n = 24.

 

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