This annual is widespread in varied wet shorelines and similar habitats across the United States, without any segregates; 2n = 96. It is often associated with sandy soils (F, Y), and in Ky. appears to be much less common to absent on calcareous soils. It is often confused with strigosus in the field, but its spikelets have distinctly shorter scales, are much less flattened, and are laterally light brown with reddish speckles (versus stramineous to pale brown). Also roots are reddish, unlike any other Cyperus in Ky.