Acroceras zizanioides (Kunth) Dandy

Global description

Acroceras zizanioides is a more robust perennial herb than Acroceras amplectens, spreading stems and rooting at nodes, then straightened up to 1.20 m tall. It is an almost hairless plant. The leaves are lanceolate with a broad rounded base, with an unconsolidated membrano-ciliate ligule and ciliated sheath. The inflorescence is erect, loose and rigid. It consists of 2 to 8 linear branches bearing solitary or grouped spikelets. These lanceolate ovoid spikelets resemble those of Acroceras amplectans. The oblong grain is flattened and convex.

General habit

Vivacious herb spread and upright, rooting at nodes, measuring between 30 cm and 1.20 m in height. It is more robust than Acroceras amplectens, a species that resembles it.

Underground system

Roots fasciculate and developing at the lower nodes.

Culm

The culm is long procumbent and branched, rooted at the lower nodes. It then straightens while remaining simple or ramifying. It has many internodes. It is more or less compressed at the base and striated. It is hairless as well as the knots.

Leaf

The leaves are simple and alternate. The sheath is glabrous or almost ciliated margin. It is sometimes slightly purplish. The ligule is a short ciliated membrane. The blade is lanceolate short and broad, 4 to 15 cm long and 6 to 26 mm wide. It is flat, broadly rounded at the base, pointed and sharp end. It is hairless or finely ciliated at the base and has a small area of ​​pubescence above the ligular zone. The margin is scabrous.

Inflorescence

The inflorescence is loose and rigid, erect or leaning. It is 10 to 25 cm high. It is larger than that of Acroceras amplectens. It is composed of 2 to 8 rectilinear racemes 3 to 12 cm long which deviate a little from the main axis. They are simple or branched, spine more or less triquera and glabrous. They are solitary, gathered by 2 or in groups.

Spikelets

The spikelets are pedicellate and lanceolate oval in shape, they measure 4.5 to 6.5 mm long. They are glabrous, pale green in color and can be tinged with purple. The glumes are membranous, with a dorsal hull and a crest at the top. The oval lower glume, with 3 veins, measures ¾ of the length of the spikelet. The superior oblong, 5-veined is the length of the spikelet. The spikelet is composed of 2 flowers. The lower flower is sterile with the lower lemma similar to the upper glume. The upper flower is fertile and oblong and leathery. The lemmas are whitish. The lower lemma has a greenish crest at the top. The upper lemma is traversed by 2 hulls whose end is bent.

Seed

The grain is oblong, flattened and convex.

https://www.gbif.org/species/4139637