Ischaemum ciliare Retz.

synonyms: Ischaemum indicum, Ischaemum timorense [misapplied in Hawai'i]


Nahiku grass


Info

Subfamily: Panicoideae
Genus etymology: Ischaemum = "to stop bleeding" [Greek] referencign supposed medical uses
Species etymology: ciliare = "ciliate" [Latin] refering to the hairs of the pedicels
Photosynthetic type: C4 (warm season)
Nativity: naturalized - accidental
First recorded in Hawaiʻi: 1941

Map

 Distribution of Ischaemum ciliare in Hawaiʻi.

Inflorescence

Ischaemum ciliare Inflorescence

Plant

Ischaemum ciliare Plant

Spikelets

Ischaemum ciliare Spikelets
Ischaemum ciliare Spikelets
Ischaemum ciliare Spikelets

Collar

Ischaemum ciliare Collar

Description

Habit: Perennial; mat forming. Stolons present. Culms prostrate; 20-60 cm long; rooting from lower nodes. Culm-nodes glabrous, or bearded. Ligule an eciliate membrane; 0.8-2 mm long. Leaf-blade base broadly rounded. Leaf-blades 15-35 cm long; 2.5-4 mm wide. Leaf-blade surface hirsute; hairy on both sides. Inflorescences: Inflorescence composed of racemes. Racemes 2; paired; 2-10 cm long. Rhachis fragile at the nodes; angular; ciliate on margins. Rhachis internodes oblong; 2.5-3 mm long; flat and forming a U or V shape with the pedicel in rear view. Rhachis internode tip transverse; cupuliform. Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels oblong; ciliate. Sterile Florets: Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; laterally compressed; 4-4.5 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; keeled; winged on keels; 11 -veined; mucronate. Companion sterile spikelet lemmas 2; enclosed by glumes; 1-awned; with 7-9 mm long awn. Spikelets: Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 5-6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base truncate; inserted. Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; laterally compressed; 4-4.5 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; keeled; winged on keels; 11 -veined; mucronate. Companion sterile spikelet lemmas 2; enclosed by glumes; 1-awned; with 7-9 mm long awn. Fertile Spikelets: Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 5-6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base truncate; inserted. Glumes: Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 0.8 length of spikelet; coriaceous; much thinner above; 2-keeled; keeled above; keeled laterally; winged on keel; winged broadly; winged above; 8-9 -veined. Lower glume surface convex; glabrous, or pilose. Lower glume apex dentate; 2 -fid. Upper glume lanceolate; coriaceous; much thinner above; 1-keeled; keeled above; winged on keel; winged above; 5 -veined. Upper glume awned; 1 -awned. Upper glume awn 2-2.5 mm long. Florets: Basal sterile florets male; with palea. Lemma of lower sterile floret lanceolate; 3.75-4 mm long; 0.7-0.8 length of spikelet; membranous; 3 -veined. Fertile lemma oblong; 2-2.5 mm long; membranous; without keel; 3 -veined. Lemma apex lobed; 2 -fid; incised 0.5 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 9-20 mm long overall; with twisted column. Column of lemma awn glabrous. Palea 1 length of lemma. Flowers: Anthers 3; 2-2.5 mm long. Distribution: Africa: west tropical, west-central tropical, and western Indian ocean. Asia-temperate: China and eastern Asia. Asia-tropical: India, Indo-China, and Malesia. South America: northern South America.
(Description source: Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). GrassBase - The Online World Grass Flora. Available at https://powo.science.kew.org )