feathertop Rhodes grass
A short-lived tufted grass usually growing 15-100 cm tall. Its stems are upright or spread outwards at first with upright tips. Its long and narrow leaves (5-30 cm long and 2-8 mm wide) are mostly hairless. Its greyish-green or whitish seed -heads are feathery and borne at the tips of the stems. Each seed-head has several branches (3-10 cm long) that radiate from the same point. The branches have numerous hairy flower spikelets, which leave two small bracts behind when they fall off.
This species is widely naturalised in mainland Australia (i.e. in most of Queensland, New South Wales, ACT, South Australia and the Northern Territory, in many parts of Western Australia, and in some parts of Victoria).
A weed of roadsides, footpaths, railways, disturbed sites, orchards and cultivation (e.g. cotton and sown pastures).
A short-lived (i.e. annual) tufted grass usually growing 15-100 cm tall, but occasionally reaching up to 1.2 m tall. Its flowering stems (i.e. culms) are upright (i.e. erect) or spread outwards at first with upright tips (i.e. decumbent or geniculately ascending).
Though this grass is mainly a weed of agricultural areas and habitation, it is also regarded as an environmental weed in northern Australia (i.e. in Queensland and the Northern Territory). It spreads from crops, pastures, gardens, disturbed areas and roadsides to nearby creek lines, native grasslands and coastal environs (e.g. sand dunes). Feathertop Rhodes grass (Chloris virgata) is a particularly aggressive invader of bare areas and degraded or disturbed native vegetation, and can out-compete native species in these habitats.
"The stems (i.e. culms) are often bent at the lower joints (i.e. nodes) and rooting may occur (i.e. adventitious roots) where these joints are close to the ground. These stems are hairless (i.e. glabrous) and have swollen joints (i.e. nodes).
The leaves consist of a sheath, which partially encloses the stem, and a spreading leaf blade. They are clustered at the base of the plant and alternately arranged along the stems. The leaf blades (5-30 cm long and 3-8 mm wide) are very narrow (i.e. linear) with entire margins and narrow gradually to a point at the tip (i.e. attenuate apex). They are mostly hairless (i.e. glabrous) or sometimes with a few spreading hairs (i.e. sparsely pubescent). Where the leaf sheath meets the leaf blade there is a tiny membrane (0.5-1 mm long) topped with tiny hairs (i.e. the ligule is a ciliate membrane), with larger hairs at its edges."
"The feathery seed-heads (i.e. inflorescences) are borne at the top of the upright flowering stems (i.e. culms). They consist of several (4-19) branches (i.e. spikes) that radiate outwards from the same point (i.e. the inflorescence is digitate). The greyish-green to whitish flowering branches (3-10 cm long) are held close together and usually borne in a upright position. Each flowering branch has numerous small, hairy, flower spikelets arranged along it. These flower spikelets (2.5-4.5 mm long) consist of a pair of bracts (i.e. glumes) 1.5-4-3 mm long and two tiny flowers (i.e. florets). The upper floret is barren while the lowest one in each spikelet normally produces a seed (i.e. the lowest is bisexual while the upper is sterile). The florets have two floral bracts (i.e. lemma and palea), three stamens and an ovary topped with a feathery two-branched stigma. Each flower spikelet is also topped with two small awns (5-15 mm long). Flowering occurs mostly during summer.
As the flower spikelets mature they turn greyish or straw-coloured and eventually fall off, leaving the pair of bracts (i.e. glumes) remaining on the seed-head branches. The yellowish seeds (i.e. grains or caryopses) are narrowly oval in shape (i.e. ellipsoid), but somewhat flattened (i.e. laterally compressed), and 1.5-2 mm long. However, they remain hidden within the old flower parts (i.e. lemma and palea)."
This species reproduces mainly by seed, which may be spread by wind and water, and may also become attached to clothing, animals, vehicles and machinery. They may also be spread by slashers, graders, and in contaminated agricultural produce (e.g. pasture seed).
"Feathertop Rhodes grass (Chloris virgata) can be easily confused with Rhodes grass (Chloris gayana ) and purpletop Rhodes grass (Chloris inflata ). These species can be distinguished by the following differences:
■feathertop Rhodes grass (Chloris virgata) has very feathery seed-heads that are initially greyish-green in colour and usually borne in a more upright position. Its flower spikelets of have two relatively large awns (5-15 mm long) and are hairy towards their tips.
■Rhodes grass (Chloris gayana ) has seed-heads that are initially greenish-brown in colour and spreading or drooping in nature. Its flower spikelets have one small and one very small awn (both usually less than 6 mm long) and are not very hairy.
■purpletop Rhodes grass (Chloris inflata ) has seed-heads that are initially purplish in colour and spreading or drooping in nature. Its flower spikelets have three relatively small awns (all less than 7 mm long) and are hairy towards their tips.
It is also relatively similar to several native windmill grasses (Chloris spp.). However, these natives are usually shorter-lived (i.e. annuals), much smaller in stature (less than 70 cm tall), and always have less than ten seed-head branches."