Directory       News       Site Map       Home
         
    Jepson eFlora
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.

 

SPOROBOLUS DROPSEED, SACATON

Michael Curto


Annual, perennial herb. Stem: generally ascending to erect, 2–20 dm, generally tufted, ± solid in ×-section. Leaf: generally basal; cauline few, ascending or curving away; distal sheath margin and collar glabrous or hairy; ligule < 1 mm, hairy or membranous, fringed; blade flat to inrolled, generally glabrous or scabrous, occasionally short-soft-hairy. Inflorescence: terminal, also occasionally axillary, panicle- or spike-like, generally partly enclosed by sheath; branches spreading or appressed. Spikelet: < 6 mm, generally pale to gray-green or ± purple; glumes generally unequal, upper < or > lemma, membranous to translucent, 1-veined; floret bisexual, generally breaking above glumes; lemma texture generally like glumes, 1(3)-veined; palea < or > lemma. Fruit: 1–3 mm, generally falling from floret, generally gelatinous when wet.
± 150 species: America, Eurasia, Africa, Australia. (Greek: to throw seed, from deciduous seeds) [Peterson et al. 2003 FNANM 25:115–139]
Unabridged references: [Baaijens & Veldkamp 1991 Blumea 35: 393–458; Colbry 1957 Cont US Natl Mus 34:1–24; Veldkamp 1990 Taxon 39:327–328]

Key to Sporobolus

1. Annual; inflorescence 1–5 cm, terminal and axillary at ± most stem nodes; upper glume 2.5–5 mm; lemma leathery, tip beaked ..... S. vaginiflorus

1' Perennial herb; inflorescence 8–80 cm, generally terminal, sometimes axillary at some stem nodes; upper glume 0.5–3 mm; lemma membranous, tip obtuse to acute

2. Sheath collar with conspicuous hairs to 4 mm; glume back keeled, upper glume midvein ± scabrous at 20×

3. Lower 1° inflorescence branches generally < 2 cm, bearing 2° inflorescence branches and spikelets to near base ..... S. contractus

3' Lower 1° inflorescence branches > 3 cm, bearing 2° inflorescence branches and spikelets along upper 3/4, base naked

4. 2°, 3° inflorescence branches weakly spreading or appressed, ± obscure ..... S. cryptandrus

4' 2°, 3° inflorescence branches spreading, evident, entangled ..... S. flexuosus

2' Sheath collar glabrous or with sparse long hairs to 6 mm; glume back rounded, upper glume midvein ± smooth at 20×

5. Upper glume length < 0.6 × lemma, tip obtuse, minutely toothed; anthers 0.5–1.1 mm ..... S. indicus

5' Upper glume length > 0.6 × lemma, tip acute, entire; anthers 1.1–1.8 mm

6. Stem generally 3–10 dm, to ± 3 mm thick at base; 2° inflorescence branches spreading, bearing spikelets distally, base naked, 3° inflorescence branches spreading ..... S. airoides

6' Stem generally 9–25 dm, to ± 9 mm thick at base; 2° inflorescence branches weakly spreading or appressed, bearing spikelets to near base, 3° inflorescence branches appressed ..... S. wrightii

Contact/Feedback

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].
We encourage links to these pages, but the content may not be downloaded for reposting, repackaging, redistributing, or sale in any form, without written permission from The Jepson Herbarium.