Ixophorus unisetus (K.[C.?] Presl) Schlechtend., Poaceae

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Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Other Latin names:  Urochloa uniseta J. Presl

Common name(s): [more details]

English: crane grass, flatstem, Mexican grass, turkey grass

Spanish: hático, pitillo, zacate blanco

Habit:  grass

Description:  "Habit: Perennial; caespitose. Basal innovations flabellate. Culms 50-140 cm long. Ligule an eciliate membrane; 1-2.5 mm long. Leaf-blades 25-75 cm long; 10-25 mm wide. Inflorescence composed of racemes. Racemes numerous; borne along a central axis; unilateral; 2-8 cm long. Central inflorescence axis 10-25 cm long. Rhachis angular; terminating in a barren extension; extension bristle-like. Spikelet packing abaxial; regular; 2 -rowed. Spikelets subtended by an involucre. Fertile spikelets sessile; 1 in the cluster. Involucre composed of bristles; 5-10 mm long. Involucral bristles persistent; few; 1 per spikelet; flexible; viscid. Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 3.5-4.7 mm long; falling entire. Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.7-1.5 mm long; 0.2-0.3 times length of spikelet; herbaceous; without keels; 3 -veined. Lower glume apex acute. Upper glume ovate; 3.5-4.7 mm long; 1.75 times length of adjacent fertile lemma; herbaceous; without keels; 9-11 -veined. Upper glume apex acute. Florets: Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 times length of spikelet; cartilaginous; 5 -veined; acute. Palea of lower sterile floret becoming indurate on flanks at maturity (and orbicular); winged on keels. Fertile lemma elliptic; 2-3 mm long; indurate; without keel. Lemma surface papillose. Lemma margins involute. Lemma apex apiculate. Palea indurate"  (GrassBase).

"The root is fibrous and the stem is decumbent, 60 to 100 centimeters tall, broad and flat at the base and light green in color.  The leafves are linear-lanceolate, 30 centimeters long and 2 centimeters wide.  The inflorescence is a panicle and the fruit is a caryopside"  (Cardenas et al., 1972; p. 31).

Habitat/ecology:  "A common grass in pastures and roadsides"  (Cardenas et al., 1972; p. 31).

In Hawai‘i, introduced in experimental plots and grown in test pastures.  Present status unknown, possibly naturalized (Herbst & Wagner, 1999; p. 27)

Propagation:  Seed (Cardenas et al., 1972; p. 31).

Native range:  Cuba, Mexico, Central America and northern South America (GRIN).

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	Kaua‘i Island	introduced invasive	Herbst, Derral R./Wagner, Warren L. (1999) (p. 27) Vouchers cited: Caum s.n. (BISH 119543), Caum s.n. (BISH 119544) Present status unknown
State of Hawaii Hawaiian Islands	Lāna‘i Island	introduced invasive	Herbst, Derral R./Wagner, Warren L. (1999) (p. 27) Vouchers cited: No name 708 (BISH 119542), Munro 532 (BISH) Present status unknown
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive	Herbst, Derral R./Wagner, Warren L. (1999) (p. 27) Vouchers cited: Cooke 7 (BISH), Brown 1471 (BISH), Krauss s.n. (BISH 119548) Present status unknown

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)
Costa Rica Costa Rica	Costa Rica (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
El Salvador El Salvador	El Salvador (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Guatemala Guatemala	Guatemala (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Honduras Honduras	Honduras (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Mexico Mexico	Mexico (United Mexican States)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Nicaragua Nicaragua	Nicaragua (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)

Additional information:
Additional online information about Ixophorus unisetus is available from the Hawaiian Ecosystems at Risk project (HEAR).

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

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

References:

Cardenas, Juan/Reys, Carlos E./Doll, Jerry D./Pardo, Fernando. 1972. Tropical weeds; malezas tropicales, vol. 1. International Plant Protection Center, Oregon State University, Corvallis. 341 pp.

Clayton, W.D./Harman, K.T./Williamson, H. 2011. World Grass Species: Descriptions, Identification, and Information Retrieval [GrassBase - The Online World Grass Flora]. The Board of Trustees, Royal Botanic Gardens, Kew.

Herbst, Derral R./Wagner, Warren L. 1999. Contributions to the flora of Hawai‘i. VII. In: Evenhuis, Neal L. and Eldredge, Lucius G., eds. Records of the Hawaii Biological Survey for 1998. Part 1: Articles. Bishop Museum Occasional Papers. 58:12-36.

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.