Goldentop Grass

675-1000 m.

Tufted annual; culms 7-15(-25) cm high, erect or geniculately ascending. Leaf-blades 2-14 cm long, 1-10 mm wide, glabrous, scaberulous on the margins; uppermost sheaths slightly inflated. Panicle 2-6 cm long, 1-2.5 cm wide, usually golden-yellow but sometimes tinged with purple. Spikelets pedicellate in groups of 2-5 at the ends of the branches, the pedicels villous. Sterile spikelet: 5-8 mm long; glumes linear-lanceolate; lemmas numerous, ovate, distichous, imbricate. Fertile spikelet: 2-3 mm long; glumes linear-lanceolate; fertile lemma ovate, 2-toothed at the apex and with a long awn from the sinus; sterile rudiment with a long awn.

Distribution: Pakistan (Punjab & N.W.FP.); Canary Is. and Madeira; Mediterranean region eastwards to southern USSR; Ethiopia; introduced elsewhere.

Fl. & Fr. Per.: March-May.

Annuals, Aquatic, leaves emergent, Terrestrial, not aquatic, Stems nodes swollen or brittle, Stems erect or ascending, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stems branching above base or distally at nodes, 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 base, Leaf sheath mostly closed, Leaf sheath smooth, glabrous, Leaf sheath or blade keeled, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades lanceolate, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence a contracted panicle, narrowly paniculate, branches appressed or ascending, Inflorescence a dense slender spike-like panicle or raceme, branches contracted, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence single raceme, fascicle or spike, Inflorescence with 2-10 branches, Flowers bisexual, Spikelets pedicellate, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets with 8-40 florets, Spikelets 1-4 in short bristly fascicles, Spikelets in groups of 7, 1 fertile, the others sterile, Spikelets bisexual, Inflorescence disarticulating between nodes or joints of rachis, rachis fragmenting, Spikelets disarticulating below the glumes, Spikelets falling with parts of disarticulating rachis or pedicel, Spikelets in dense head-like clusters, Spikelets secund, in rows on one side of rachis, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes equal to or longer than adjacent lemma, Glume equal to or longer than spikelet, Glumes 1 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma 5-7 nerved, Lemma glabrous, Lemma apex acute or acuminate, Lemma distinctly awned, more than 2-3 mm, Lemma with 1 awn, Lemma awn less than 1 cm long, Lemma awned from tip, Lemma awns straight or curved to base, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea about equal to lemma, Palea longer than lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis.

Lamarckia is a Eurasian and African plant in the grass family.

Species

The only known species is Lamarckia aurea, the golden dog's-tail or goldentop grass It is an annual plant, typically 30-45 centimetres in height, with clusters of golden flowers in a panicle 5–8 cm long and 2–2.5 cm broad. The species is native to the Mediterranean Basin and neighboring regions from Portugal to the Canary Islands east to Ethiopia and northern India. It is also naturalized in parts of Australia and the Americas, considered an invasive weed in some areas.

Formerly included

see Aegopogon

Lamarckia tenella - Aegopogon tenellus