Panicum capillare L.
Family: Poaceae, Tribe: Paniceae
Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)
including ssp. capillare & ssp. hillmanii (Chase) Freckmann & Lelong
Pertinent Common Names (particularly those used in California; go to GRIN for other common names)
witchgrass
Primary Disseminule Type
spikelet, floret
Description (diagnostics are in brown)
Spikelets solitary, pedicelled, elliptic or oblong, dorsally compressed, 1.8–4 mm long x 1–1.5 mm wide x 0.9–1 mm thick, light green or purplish, glabrous except at tip, consisting of one basal sterile floret and one fertile floret without rachilla extension. Disarticulation at base of each spikelet (though sometimes whole inflorescences detach from plant and fertile florets detach from spikelet).
Glumes ovate, dissimilar, reaching apex of florets, thinner than fertile lemma, membranous, without keels. Lower glume 0.33–0.5 length of spikelet, enwrapping base of spikelet, 1–5-veined, apex obtuse to acuminate. Upper glume same length as spikelet, 5–9-veined, apex acuminate.
Sterile lemma similar to upper glume (ovate, same length as spikelet, membranous), extending beyond the upper fertile floret, 5–7-veined, veins prominent distally, apex acute. Sterile palea absent (ssp. capillare) or 0.5 length of sterile lemma (ssp. hillmanii).
Fertile lemma elliptic, dorsally compressed, 1.5–2 mm long, indurate, without keel, straw-colored (ssp. capillare) to very dark brown with pale veins, shiny, glabrous, surface faintly striolate, margins involute, apex acute, with a crescent-shaped scar at base (ssp. hillmanii only).
Fertile palea indurate, margins involute.
Caryopsis broadly elliptic to broadly oblong, ca. 1.5 mm long x ca. 1 mm wide, straw-colored, embryo 0.4–0.5 length of caryopsis, hilum round.
Similar Species
Similar Species Comparison Chart
Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)
AUQP, NZWP, NZBORIC, NZBPI