=Andropogon pumilus, _Roxb._=
It is a tufted annual with numerous radiating branches, growing on all directions, bent below and erect above; they vary in length from 6 inches to 18 inches, but sometimes when growing under favourable conditions attain the length of 2-1/2 feet. The stem is slender, green, or pale reddish in the exposed portions and pale in parts covered by sheaths slightly flattened, smooth.
The _leaf-sheaths_ are smooth, compressed, distinctly keeled. The _ligule_ is a short, truncate, white, glabrous membrane. The _nodes_ are glabrous.
The _leaf-blade_ is linear, finely ac.u.minate, glabrous, but sometimes somewhat scabrid along the nerves and with scattered long delicate hairs above especially when young, varying in length from 1 to 7 inches and 1/10 to 1/8 inch in breadth.
The _inflorescence_ consists of paired spikes with very slender peduncles arising from flattened, glabrous, ac.u.minate spathes, varying in length from 1/2 to 1-1/4 inches. The _spikes_ are spreading and one of them always slightly longer than the other, reddish or pale green, 1/2 to 1 inch long; the _rachis_ consists of five to eight flat joints broadened at the top and ending in a cup, densely ciliate on both the margins, but hairs on one margin are shorter than those on the other.
Each joint bears a sessile and a pedicelled spikelet.
[Ill.u.s.tration: Fig. 151.--Andropogon pumilus.
1. A portion of the spike to show the arrangement of the spikelets; 1.
the first glume of the sessile spikelet; 2. second glume of the sessile spikelet; 3 and 4. third and fourth glumes of the sessile spikelet; 5.
anthers, lodicules and the ovary; A, B and C. the three glumes of the pedicelled spikelets.]
The _sessile spikelet_ is about 3/16 inch with an awn 7/16 inch long.
There are four _glumes_ in the spikelet. The _first glume_ is narrow, linear, membranous, grooved, finely bicuspidate at the apex, with incurved margins and two nerves ending in tubercles below. The _second glume_ is a little longer than the first, narrow, lanceolate, boat-shaped, thinly coriaceous with membranous margins, 1-nerved and shortly awned. The _third glume_ is about 2/3 of the second glume in length, and shorter than the first glume, linear-lanceolate, hyaline, nerveless or sometimes very obscurely 2-nerved. The _fourth glume_ is narrow linear, hyaline with two very fine lobes at the apex with an awn between, 7/16 inch long. _Palea_ is hyaline and very small. _Stamens_ are three, _ovary_ with two long reddish feathery _stigmas_. _Lodicules_ small and cuneate. Grain is long and narrow.
The _pedicelled spikelets_ have only three glumes, and are slightly shorter than the sessile ones, pedicel is similar to the joint. The _first glume_ is ovate-lanceolate, thinly coriaceous, distinctly many-nerved, ac.u.minate, margins infolded and membranous. The _second glume_ is ovate-lanceolate, membranous, glabrous and 3-nerved. The _third glume_ is short, oblong-lanceolate, nerveless or faintly 2-nerved. There are three stamens.
This gra.s.s is variable in its size. In dry soils such as laterite soils, it is a very small plant not exceeding 9 or 10 inches across its spread.
But in good soil and under favourable conditions the plant measures across 5 or 6 feet. Cattle eat the gra.s.s before it flowers and do not relish it so much when in flower.
A common gra.s.s flourishing all over the Presidency.
_Distribution._--Occurs in drier parts throughout India.
[Ill.u.s.tration: Fig. 152.--Andropogon pertusus.]
=Andropogon pertusus, _Willd._=
This gra.s.s is perennial. Stems are tufted, very slender, widely creeping on all sides, purplish, but the flowering branches are erect or ascending from a geniculate base, leafy at base, the nodes of the creeping branches rooting and bearing tufts of branches which finally become independent plants at each node, the creeping branches vary in length from 1 to 3 feet and the erect ones from 10 to 18 inches or more.
The _leaf-sheaths_ are terete or somewhat compressed, glabrous, sometimes ciliated near the node and shorter than the internode. The _ligule_ is a truncate membrane, slightly ciliate or not. _Nodes_ are bearded.
The _leaf-blades_ in the prostrate branches are crowded, short linear-lanceolate, finely ac.u.minate, soft, shortly hairy along the nerves, spa.r.s.ely ciliate near the rounded base, varying in length from 1 to 2 inches and in breadth 1/8 to 1/4 inch; but on the flowering branches the leaves are longer, sometimes as long as twelve inches with bigger sheaths.
[Ill.u.s.tration: Fig. 153.--Andropogon pertusus.
1. A portion of a spike; 2. a pair of spikelets; a. sessile and b.
pedicelled; a-1. first glume; a-2. second glume; a-3. third glume; a-4.
fourth glume and awn; a-5. ovary and stamens; a-6. grain; b-1. first glume of pedicelled spikelet front and back; b-2. second glume front and back; b-3. third glume.]
The _inflorescence_ consists of three to nine, slender, flexuous, erect, purplish spikes, 1 to 2 inches long, alternately arranged on a thin, long, slender, smooth peduncle of about six inches; _rachis_ is slender and the joints and pedicels are densely silky with long hairs.
The _spikelets_ are in pairs, one sessile and one-pedicelled, both are equal, purplish or pale. The _sessile spikelet_ consists of four glumes and contains a complete flower and the callus is short and bearded with long hairs. The _first glume_ is coriaceous, oblong-lanceolate, acute, truncate or emarginate, slightly hairy, or glabrous with a deep pit above the middle (sometimes with two or three pits also) 7- to 9-nerved with a few long hairs below the middle and with margins infolded and shortly ciliate. The _second glume_ is lanceolate-ac.u.minate and finely pointed at the tip and the point projecting slightly beyond the first glume, 3-nerved or 3- to 5-nerved, membranous, slightly hairy or glabrous, obscurely keeled. The _third glume_ is thin, membranous, shorter than the second glume, linear-oblong, subobtuse or acute at the tip and nerveless. The _fourth glume_ is the base of the awn and the _awn_ is not twisted, bent at about the middle, 1/2 to 2/3 inch long; there is no palea. _Anthers_ are three and yellow; _stigmas_ purple. The grain is oblong-obovate, slightly transparent.
The _pedicelled spikelets_ are slightly narrower than the sessile, generally not pitted (though pitted in some plants), and not awned, and each one consists of three glumes only; the pedicel is more than half as long as the sessile spikelets. The _first glume_ is slightly hairy, oblong-lanceolate, acute or obtuse, ciliate at the margins, 7- to 9-, or 13-nerved, generally without pits, but occasionally with one, two or three pits; the keels are ciliolate throughout the length. The _second glume_ is membranous, ovate-lanceolate, acute, with incurved margins, 5-nerved. The _third glume_ is hyaline, linear-oblong, glabrous and thinly ciliate at the tip or not with or without stamens.
This is an excellent fodder gra.s.s and it grows quickly and stands cutting very well. Cattle eat this gra.s.s very well.
_Distribution._--This gra.s.s is found all over India in the plains or lower elevations of hills.
=Andropogon squarrosus, _L.f._=
(_Vetiveria zizanioides._)
This is a densely tufted perennial gra.s.s with branching root-stocks and spongy aromatic roots.
The stems are leafy, with equitant, hard, leaf-sheaths at the base, smooth and polished, solid, 2 to 3-1/2 feet high.
The _leaf-sheaths_ are smooth, coriaceous, glabrous, keeled and compressed. The _ligule_ is a very short membrane.
_Leaf-blades_ are narrowly linear, erect, strongly keeled and flat, ac.u.minate, glabrous both above and below, very much narrower than the sheath at the base, 1 to 2 feet by 1/3 to 3/4 inch.
The _panicle_ is conical, erect with branches, fascicled, varying in length from 4 to 12 inches. The _spikes_ consist of both sessile and pedicelled spikelets, that are either grey, green, or purplish.
[Ill.u.s.tration: Fig 154.--Andropogon squarrosus.
1. A portion of a branch; 2. a sessile and a pedicelled spikelet; 3, 4, 5 and 6. the first, second, third and the fourth glume, respectively, of the sessile spikelet; 7. palea of the fourth glume; 8. lodicules, stamens and the ovary; 9, 10, 11 and 12. glumes of the pedicelled spikelet; 13. palea of the fourth glume.]
The _sessile spikelets_ are about 1/6 inch long, lanceolate and with a shortly bearded callus. The _first glume_ is ovate-oblong, thickly coriaceous, obscurely 2- to 4-nerved (occasionally 5- to 7-nerved), acute, dorsally flat, with incurved margins and with two rows of tubercle-based minute p.r.i.c.kles or mere excrescences at the sides. The _second glume_ is as long as the first, oblong, coriaceous, keeled, with hyaline and ciliolate margins, 1-nerved (sometimes 3-nerved, marginal faint), and with minute p.r.i.c.kles on the keel. The _third glume_ is broadly oblong, hyaline, nerveless or rarely with two obscure veins ciliolate at the margins and acute or ac.u.minate. The _fourth glume_ is shorter than the third, linear-oblong, mucronate or very shortly awned at the apex, paleate; _palea_ about two-thirds the length of the glume, lanceolate. _Lodicules_ are two, quadrate and conspicuous though small.
_Styles_ and _stigmas_ short. _Stamens_ are three with yellow anthers.
_Stigmas_ are purple.
The _pedicelled spikelets_ are similar to the sessile ones, but are slightly smaller and the p.r.i.c.kles are less prominent. The _fourth glume_ has no mucro or awn and has three stamens.
This gra.s.s is fairly abundant in moist situations, in the margins of tanks and in tankbeds in the Coromandel districts, but in other inland districts it is not so common. In some places it seems to be cultivated.
This is the _khus-khus_ gra.s.s.
_Distribution._--Throughout the plains and lower hills of India, Burma and Ceylon, also said to occur in Java and Tropical Africa.
=Andropogon asper, _Heyne._=
(_Chrysopogon asper_, Heyne.)
This is a tufted perennial gra.s.s. Stems are stout below with distichous leaves and very slender above, 2 to 3-1/2 feet long.
The _leaf-sheaths_ are distichous and towards the base of the stem are 1/2 inch broad, compressed, keeled and with scattered tubercle-based hairs. The _ligule_ is a short membrane fringed with close set hairs.
[Ill.u.s.tration: Fig. 155.--Andropogon asper.
Leafy shoot, a bit of the stem with leaf-sheaths and a bit of the leaf.]