Scirpus maritimus, alkali bulrush

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Intermountain Flora
Stout, rhizomatous perennial 2-15 dm tall, the rhizomes commonly bearing firm tubers; culms sharply triquetrous, often with concave sides; leaves usually several, well developed, elongate, flat or nearly so, up to about 1 cm wide, well distributed along the stem, or all borne below the middle; spikes 3-20 or more, 1.2-2 cm long and 6-10 mm thick, usually rather blunt, all sessile in a compact terminal cluster, or the principal cluster somewhat surpassed by one or more short peduncles bearing each a subsidiary cluster; involucral bracts several, very unequal, 2-4 of them more or less elongate, green and leafy-textured (occasionally anthocyanic at the base), surpassing the others; scales tan or light brown or sometimes darker brown, thin and more or less hyaline-scarious, minutely hirtellous-puberulent on the back, short-awned from a notched (often somewhat irregularly lacerate) tip; bristles retrorsely barbellate, rather poorly developed, up to about half as long as the achene, or often obsolete; style branches 2; achene lenticular, 2.5-4 mm long, apiculate, minutely cellular-reticulate (obscurely so at 10x, somewhat more evidently so at 20x); n= 40, 43, 48, 53, 55, 57.

Cronquist, A., Holmgren, A.H., Holmgren, N.H., Reveal, J.L., and Holmgren, P.K. (1977) "Intermountain Flora" pg. 72, vol. 6, The New York Botanical Garden New York.