Paspalum vaginatum Sw.

Global description

Paspalum vaginatum is a vivacious, erect herb, glabrous, with stoloniferous stems, reaching 60 cm in height. The leaves are stiff and distichous, blue-green in color. They have a compressed sheath, a  membrane-ciliated ligule, a linear leaf lamina with acute apex, flat, with a smooth margin. The terminal inflorescence is composed of 2 to 3 digitate racemes slightly externalized. The spikelets are subsessile, ovoid lanceolate, flattened and are inserted in 2 series located on either side of the rachi. Each spikelet contains a single fertile flower. The grain is, compressed, oblong and shortly apiculate.

First leaves

 

The prefoliation is rolled.

General habit

Vivacious grass with creeping rhizomes and stolons 8 to 60 cm high.
 
Underground system

The roots are fibrous. They also appear at the nodes of crawling stolons.
 
Culm

The culm is erect, glabrous, radicant at the base, simple or branched, with an elliptical cross-section. It has many nodes wrapped in the leaf sheaths. It emits more or less thick stolons, which branch. These stolons are covered with large overlapping sheaths.
 
Leaf

The leaves are simple, alternate. They are rigid ascending, distichous, with overlapping sheaths. The sheath is glabrous (sometimes it has few hairs at the apex), more or less compressed. The membraneous ligule is very short and is topped by a row of long bristles. The lamina is 2.5 to 15 cm long and 3 to 8 mm wide. The lamina is linear, with tapered end in an acute apex. It is flat or folded, often rolled up, keeled, glabrous and with smooth margin, blue-green in color.
 
Inflorescence

The inflorescence is terminal. It consists of 2 or 3 digitate racemes, slightly externalized, 1.5 to 7.5 cm long, straight or slightly arched, diverging at maturity. The rachi of the racemes are 1mm large, winged with scabrous margins. The spikelets are biseriate, densely layered and applied on the rachis in 2 rows.
 
Spikelet

The spikelets are 3 to 4.5 mm long. They are subsessile, ovoid lanceolate, pointed, flattened, and glabrous. The lower glume is absent (rarely in small scale). The upper glume is as long as the spikelet, papery, acute tip, with 4 to 5 veins on the dorsal side. The lower flower is sterile, reduced to its lemma which is similar to upper glume. The upper flower is fertile. It is oblong elliptic, with pointed tip, pale yellow in colour. Its papery lemma are the same size. The flower has 3 stamens, 2 free styles with purple feathery stigmas, which emerges laterally.
 
Grain

Compressed grain, oblong and shortly apiculate, 2 mm long and 1 mm wide.