Classification
 Nomenclature
Scientific Name:
Panicum dichotomiflorum Michx. (1803)
Vernacular Name(s):
Smooth witchgrass
 Description

Almost glabrous, tufted summer annuals. Leaf-sheath light green to commonly purplish, submembranous, flattened, rounded, glabrous. Ligule 1–2 mm, a membranous densely ciliate rim. Leaf-blade 7–30 cm × 3–5.5 mm, ± rounded at base, narrowed above, dull green to purplish, glabrous, abaxially slightly keeled, adaxially channelled, rarely with scattered, long, fine hairs; margins finely scabrid, tip acuminate. Culm 20–60 cm, often geniculate at base, almost prostrate and rooting at lower nodes, or ascending or ± erect, internodes glabrous or slightly hairy near nodes. Panicle 8.5–35.5 × 1.5–7–(15) cm, usually not fully emergent from leaf-sheath; branches fine, smooth, ascending to later spreading, branchlets and pedicels shorter, finer, scabrid, tipped by ± close-set spikelets. Spikelets 2.8–3.3 mm, glabrous, light green to purplish, narrow elliptic-oblong, much narrowed to acute tip. Glumes very unequal; lower c. 1 mm, ovate, sometimes slightly notched at broad acute tip, 3-nerved, upper = spikelet, (7)–9-nerved, elliptic, tapering above to acute tip. Lower floret Ø: lemma slightly < upper glume, (7)–9-nerved; palea shorter and much narrower than lemma, 2-keeled, keels glabrous. Upper floret ☿: lemma c. 2 mm, elliptic, subacute, faintly striolate, glabrous, shining, light cream; palea narrower; anthers 1–1.5 mm; caryopsis c. 1.5 × 0.8 mm.

[From: Edgar and Connor (2000) Flora of New Zealand. Volume 5 (second printing).]

 Biostatus
Exotic