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Key to families | Table of families and genera

Specimen numbers are hyperlinked to records in the Consortium of California Herbaria data view where possible. Taxa are hyperlinked to entries in the Jepson Interchange via the "[Online Interchange]" link.

 

BOUTELOUA GRAMA

J. Travis Columbus


Annual, perennial herb, generally cespitose. Stem: solid, generally glabrous. Leaf: generally basal; ligule generally < 1 mm, generally hairy; blade flat to inrolled, adaxial surface generally puberulent or short-hairy, often ciliate near ligule, hairs long, bulbous-based. Inflorescence: generally panicle-like; branches spike-like, 1 per node, persistent or deciduous in fruit; spikelets 2-rowed on 1 side of axis, overlapping. Spikelet: sessile or short-stalked, ± cylindric to laterally compressed; glumes generally unequal, generally lanceolate, 1-veined, upper glume firmer than lower; axis (if inflorescence branch persistent) breaking between glumes and lower floret; florets generally 2–3, lower floret bisexual, > upper, upper floret(s) generally reduced, sterile; lemma 3-veined, generally 3-awned, awns straight, scabrous; palea ± = lemma.
57 species: America. (Claudio (b. 1774) and Esteban (b. 1776) Boutelou, Spanish botanists, horticulturists) [Columbus 1999 Aliso 18:61–65] Many species important for forage.

Key to Bouteloua

1. Annual

2. Spikelets 1–4 per inflorescence branch; branch axis prolonged beyond terminal spikelet node generally > 5 mm; inflorescence branches deciduous in fruit, spikelets falling with branch ..... B. aristidoides var. aristidoides

2' Spikelets > 6 per inflorescence branch; branch axis terminated by spikelet; inflorescence branches persistent, spikelet axis breaking between glumes and lower floret

3. Tip of lower floret lemma 2-lobed, central awn from sinus; base of middle or, if only 2 florets, upper floret hairy-tufted ..... B. barbata var. barbata

3' Tip of lower floret lemma tapered to central awn; base of upper floret glabrous ..... B. trifida (2)

1' Perennial herb — rhizomes or stolons sometimes present

4. Inflorescence branches 13–60, deciduous in fruit, spikelets falling with branch ..... B. curtipendula

4' Inflorescence branches < 8, persistent in fruit, spikelet axis breaking between glumes and lower floret

5. Lower stem internodes hairy; inflorescence branch axis slightly prolonged beyond terminal spikelet node ..... B. eriopoda

5' Lower stem internodes glabrous or minutely scabrous; inflorescence branch axis terminated by fertile or vestigial spikelet

6. Base of middle or, if only 2 florets, upper floret hairy-tufted; tip of lower floret lemma 2-lobed, central awn from sinus ..... B. gracilis

6' Base of upper floret glabrous; tip of lower floret lemma tapered to central awn ..... B. trifida (2)

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Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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