Schizachyrium condensatum (Kunth) Nees, Poaceae

Click on an image for links to BIGGER PICTURES

Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Risk assessment results:  High risk, score: 13 (Go to the risk assessment)

Other Latin names:  Andropogon condensatus Kunth

Common name(s): [more details]

English: bush beardgrass, little bluestem

Spanish: aguará ruguay, yerba barbuda

Habit:  grass

Description:  "Perennial [grass]; culms tufted, erect, 9-15 dm tall, unbranched in lower part, repeatedly branching above into a compound inflorescence, internodes 2-3.5 mm in diameter, glabrous, broadly elliptic in cross section, filled with white or pinkish pith, nodes inconspicuous, glabrous.  Sheaths keeled, glabrous, rarely sparsely puberulent; ligule a firm membrane, 0.7-2 mm long, adnate to sheath margins; blades up to 40 cm long, 3-8 mm wide, glabrous, lower surface keeled, occasionally with a few hairs at throat.  Inflorescences loose, composed of numerous solitary racemes subtended by spathes, 20-40 cm long, 3-8 cm wide, branched in upper part, peduncles 2.5-6 cm long, with up to 8 spikelet pairs, individual racemes on slender branches, spathes involute or flattened, somewhat concealing the lower spikelet pairs, 15-35 mm long, rachis internodes 4-6 mm long, widened upward, conspicuously ciliate on the edges, pedicels 3.6-5.5 mm long; sessile spikelets narrowly ovate, 4.5-5 mm long, callus blunt, minutely bearded, hidden by the hollow apex of the rachis internode, glumes subequal, as long as the spikelet, first glume slightly convex on the back, with 2 submarginal keels, apex slightly bidentate, second glume slightly shorter than first glume, 1-nerved, strongly keeled, the keel scabrous, first lemma 3.2-3.8 mm long, hyaline, ciliolate on the margins, apex acute, second lemma hyaline, apex deeply bifid, ciliolate, awned, the awn dark brown and strongly twisted below, the exserted portion above the bend straight or loosely twisted, ca. 10 mm long, palea absent; pedicellate spikelet sterile, usually 1-2 mm long, awn straight, up to 2 mm long.  Caryopsis amber, linear-cylindrical, 2.5-2.8 mm long"  (Wagner et al., 1999; p. 1590).

Description from GrassBase.

Habitat/ecology:  "Wood- and shrubland, grassland, disturbed sites.  This fast growing grass send up new tillers each year from a small root corwn.  The grass is invasive because it promotes the spread of fires and displaces native vegetation with pure stands.  Such stands accumulate laarge quantities of dead and flammable biomass, increasing fire frequency and intensity.  The grass forms dense swards that crowd out native plant species and prevent their regeneration"  (Weber, 2003; p. 391).

In Hawai‘i, "naturalized along roadsides and in open sites in mesic shrubland and grassland, 210-1,310 m" (Wagner et al., 1999; p. 1590); "forms dense stands in disturbed areas of pastures and forests; a fire hazard"  (Motooka et al., 2003).

Propagation:  Seed

Native range:  Tropical and subtropical America.

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 1590) Voucher cited: Fosberg 42065 (BISH)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Lorence, David H./Flynn, Timothy W./Wagner, Warren L. (1995) (p. 47) Vouchers cited: L. Hume & R. Levine 411 (PTBG, US), T. Flynn et al. 3547 (BISH, F, MO, MU, NY, OS, PTBG, US), T. Flynn et al. 2717 (PTBG), W.L. Wagner & R. Hanford 6278 (US), T. Flynn et al. 2679 (PTBG)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Frohlich, Danielle/Lau, Alex (2012) (p. 45) Voucher cited: A. Lau & D. Frohlich 2010021701 (BISH)

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Colombia Colombia	Colombia (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Ecuador (Mainland) Ecuador	Ecuador (Republic of) (continental)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Mexico Mexico	Mexico (United Mexican States)		Hafliger, Ernst/Scholz, Hildemar (1980) (p. 120)
Perú Perú	Perú (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)

Indian Ocean
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
British Indian Ocean Territory Chagos Archipelago	Diego Garcia Island	introduced invasive	Rivers, Julie (2004) (p. 2)

Control: 

Physical:  "In pastures, grazing management and cultural measures probably more promising"  (Motooka et al., 2003).

Chemical: "Sensitive to glyphosate.  HAVO staff reported control with foliar application of glyphosate at 1% of product in water (Chris Zimmer, HAVO)"  (Motooka et al., 2003).

Additional information:
Excerpt from the book "Weeds of Hawaii‘s Pastures and Natural Areas; An Identification and Management Guide" (Motooka et al., 2003). (PDF format).

Additional online information about Schizachyrium condensatum is available from the Hawaiian Ecosystems at Risk project (HEAR).

Information about Schizachyrium condensatum as a weed (worldwide references) may be available from the Global Compendium of Weeds (GCW).

Taxonomic information about Schizachyrium condensatum may be available from the Germplasm Resources Information Network (GRIN).

References:

Frohlich, Danielle/Lau, Alex. 2012. New plant records for the Hawaiian Islands 2010-2011. In: Evenhuis, Neal L. and Eldredge, Lucius G., eds. Records of the Hawaii Biological Survey for 2011. Part II: Plants. Bishop Museum Occasional Papers. 113:27-54.

Hafliger, Ernst/Scholz, Hildemar. 1980. Grass weeds, vol. 1. CIBA-GEIGY Ltd., Basle, Switzerland. 142 pp. + plates.

Herbst, Derral R./Staples, George W./Imada, Clyde T. 2004. New Hawaiian plant records for 2002-2003. In: Evenhuis, Neal L. and Eldredge, Lucius G., eds. Records of the Hawaii Biological Survey for 2003. Part 1: Articles. Bishop Museum Occasional Papers. 78:3-12.

Lorence, David H./Flynn, Timothy W./Wagner, Warren L. 1995. Contributions to the flora of Hawai‘i. III. New additions, range extensions, and rediscoveries of flowering plants. In: Evenhuis, Neal L. and Miller, Scott, E., eds. Records of the Hawaii Biological Survey for 1994. Part 1: Articles. Bishop Museum Occasional Papers. 41:19-58.

Meyer, Jean-Yves. 2000. Preliminary review of the invasive plants in the Pacific islands (SPREP Member Countries). In: Sherley, G. (tech. ed.). Invasive species in the Pacific: A technical review and draft regional strategy. South Pacific Regional Environment Programme, Samoa. 190 pp.

Motooka, Philip/Castro, Luisa/Nelson, Duane/Nagai, Guy/Ching, Lincoln. 2003. Weeds of Hawaii‘s Pastures and Natural Areas; An Identification and Management Guide. College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa. 184 pp.

Rivers, Julie. 2004. Botanical survey update of Diego Garcia, Chagos Archipeligo, British Indian Ocean Territory. Naval Facilities Engineering Command, Pacific. 16 pp. plus "List of the higher plants of Diego Garcia".

Snow, Neil/Lau, Alex. 2010. Notes on grasses (Poaceae) in Hawai‘i. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2008. Bishop Museum Occasional Papers 107:46-60.

U. S. Government. 2011. Integrated Taxonomic Information System (ITIS) (on-line resource).

U.S. Dept. Agr., Agr. Res. Serv. 2011. National Genetic Resources Program. Germplasm Resources Information Network (GRIN). Online searchable database.

Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. 1999. Manual of the flowering plants of Hawaii. Revised edition. Bernice P. Bishop Museum special publication. University of Hawai‘i Press/Bishop Museum Press, Honolulu. 1919 pp. (two volumes).

Weber, Ewald. 2003. Invasive plants of the World. CABI Publishing, CAB International, Wallingford, UK. 548 pp.