Bothriochloa ischaemum (L.) Keng

synonyms: Andropogon ischaemum


King Ranch bluestem, KR bluestem, yellow bluestem


Info

Subfamily: Panicoideae
Genus etymology: Bothriochloa = "pitted grass" [Greek] refering to the pits on the lower glume in most species
Species etymology: ischaemum = "styptic" [Latin] refering to a supposed ability to stop bleeding
Photosynthetic type: C4 (warm season)
Nativity: naturalized - intentional
First recorded in Hawaiʻi: 1950

Map

 Distribution of Bothriochloa ischaemum in Hawaiʻi.

Inflorescence

Bothriochloa ischaemum Inflorescence

Description

Plants usually cespitose, occasionally stoloniferous or almost rhizomatous under close grazing or cutting. Culms 30–80(–95) cm, stiffly erect; nodes glabrous or short hirsute. Leaves tending to be basal; ligules 0.5–1.5 mm; blades 5–25 cm long, 2–4.5 mm wide, flat to folded, glabrous or with long, scattered hairs at the base of the blade. Panicles 5– 10 cm, fan-shaped, silvery reddish-purple; rachises 0.5–2 cm, with (1–)2–8 branches; branches 3–9 cm, longer than the rachises, erect to somewhat spreading from the axillary pulvini, usually with only 1 rame; rame internodes with a central groove narrower than the margins, margins ciliate, with 1–3 mm hairs. Sessile spikelets 3–4.5 mm, narrowly ovate; lower glumes hirsute below, with about 1 mm hairs, lacking a dorsal pit; awns 9– 17 mm, twisted, geniculate; anthers 1–2 mm. Pedicellate spikelets about as long as the sessile spikelets, but usually narrower, sterile or staminate. 2n = 40, 50, 60.
(Description source: Barkworth, M.E., Capels, K.M., Long, S. & Piep, M.B. (eds.) 2003. Flora of North America, north of Mexico. Volume 25. Magnoliophyta: Commelinidae (in part): Poaceae, Part 2. Oxford University Press, New York. 783 pp http://floranorthamerica.org/Bothriochloa_ischaemum )