Digitaria horizontalis Willd.

4.4 Conducta

Maleza (Swallen, 1955).

1.1 Descripción de la especie

Culmos erectos o decumbentes, a menudo con raíces en los nudos inferiores, de 15 a 50 cm (1m) de longitud, glabros. Vainas papiloso-pilosa, lígula de 1.5 a 1.8 mm de largo. Lígulas de 1.5 a 1.8 mm. Láminas de 3 a 14 cm de largo, 3 a 9 mm de ancho, frecuentemente densamente pubescente en la superficie adaxial. Inflorescencia una panícula de 5 a 15 cm de longitud, con (2) 4 a 19 (15) ramificaciones primarias espigadas de 4 a 10 cm de longitud, las inferiores verticiladas, las superiores solitarios u opuestos, su raquis de 0.4 a 0.5 mm de ancho, escabroso en los márgenes. Espiguillas en pares, lanceoladas, de 1.8 a 2 (2.5) mm de largo. Glumas primera gluma deltoide, enervia, de 0.1 a 0.2 mm de longitud o a veces ausente, la segunda de 1 a 1.1mm de longitud, trinervada, ciliada. Lemas del flósculo estéril tan larga como la espiguilla, 7- nervada, ciliada; lema del flósculo estéril casi tan larga como la espiguilla, pajiza o gris, apiculada. Cariópsis cariópsis casi 1.8 mm. Flor anteras 0.8 a 1 (Barkworth et al., 2003; Rzedowski &Rzedowski, 2001).

4.7 Longevidad

Especie anual (Rzedowski, &Rzedowski, 2001).

3.4 Hábitat- SNIB - CONABIO, 2007

Hábita en suelos con disturbio, áreas cultivadas y vegetación secundaria (Basel &Berlin, 1981; Davidse et al., 1994).

Chile Central

Annuals, Terrestrial, not aquatic, Stolons or runners present, Stems trailing, spreading or prostrate, Stems nodes swollen or brittle, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems mat or turf forming, Stems terete, round in cross section, or polygonal, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at bas e, Leaf sheath mostly open, or loose, Leaf sheath hairy, hispid or prickly, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades more or less hairy, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence a panicle with digitately arranged spicate branches, Inflorescence with 2-10 branches, Inflorescence branches more than 10 to numerous, Inflorescence branches 1-sided, Lower panicle branches whorled, Peduncle or rachis scabrous or pubescent, often with long hairs, Rachis winged, Rachis angular, Flowers bisexual, Spikelets pedicellate, Spikelets dorsally compressed or terete, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets with 2 florets, Spikelet with 1 fertile floret and 1-2 sterile florets, Spikelets paired at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating below the glumes, Spikelets secund, in rows on one side of rachis, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 1 clearly present, the other greatly reduced or absent, Glumes 2 clearly present, Glumes distinctly unequal, Glumes equal to or longer than adjacent lemma, Glume equal to or longer than spikelet, Glume surface hairy, villous or pilose, Glumes 3 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma similar in texture to glumes, Lemma 5-7 nerved, Lemma apex acute or acuminate, Lemma awnless, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea about equal to lemma, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.

Digitaria horizontalis là một loài thực vật có hoa trong họ Hòa thảo. Loài này được Willd. mô tả khoa học đầu tiên năm 1809.