What Does It Look Like?
What is it?
Fountain Grass (Cenchrus setaceus) [Pennisetum setaceum] is a robust rhizomatous (with underground stem), perennial, forming large tussocks perennial grass with flowering stems to 1 m tall. The coarse stiff tough rough hairless leaves, are flat folded or inrolled, smooth and hairless (except at the very base near the sheath), and up to 60 cm long and to 4 mm wide. The leaf sheaths (part of the leaf rolled around the stem) with hairs along margins, ligules (a small appendage where the leaf sheath meets the leaf blade) is about 1 mm long with lateral tufts to 3 mm.
The flowers are numerous pale purple to pink, borne in a dense spike 10–30 cm long and 3–4 cm wide (including the bristles). Spikelets are solitary or in clusters of 2–3. Each flower spikelet contains several flowers 4–6 mm, and is surrounded by up to 25 thin stiff plumose bristles (bearing long hairs) 1.5–4 cm long with one bristle usually longer than all the others.
Fruits (seeds) are contained within the flower. Individual flowers fall as a unit surrounded by the bristles and enclosing the cylindrical grain (seed) which is smooth, wheat-coloured and about 1.8 mm long and 0.8 mm wide (Cunningham et al. 1981; Stanley & Ross 1989).
For further information and assistance with identification of Fountain Grass contact the herbarium in your state or territory.
Flower colour
Purple, Pink
Growth form (weed type/habit)
Grass
Where it currently grows? Preferred habitat
Fountain Grass is a weed of disturbed areas near habitation, along drains and roads, around dams and on farms in degraded pastures and on rocky and stony areas (Cunningham et al. 1981; Stanley & Ross 1989).
Are there similar species?
There are several introduced species of Cenchrus [as Pennisetum]. Two of these – Feathertop (C. longisetus) [as P. villosum] and African Feather Grass (C. macrourus) [as P. macrourum] – and a native species, Swamp Foxtail (C. purpurascens) [as P. alopecuroides], look superficially similar to Fountain Grass. The best diagnostic feature to separate these four species is whether the bristles surrounding the flowers are themselves plumose (hairy) or not.
Fountain Grass and Feathertop both have plumose bristles. However, they can also be distinguished by the colour of the whole inflorescence – purple or pink in Fountain Grass and creamy coloured in Feathertop. Both Swamp Foxtail and African Feather Grass both have bristles lacking hairs (Slee 2007, pers. comm.). Queens;and Overnemnt (2016) summerise the look-a-like species as follows:
Fountain grass (Cenchrus setaceus) is a moderately-sized long-lived (i.e. perennial) grass (50–150 cm tall) with relatively elongated, reddish or pinkish-coloured seed-heads. The main stem (i.e. rachis) of the seed-head is angular and the long bristles (up to 25 mm or more) are hairy (i.e. plumose).
African feather grass (Cenchrus macrourus) is a large long-lived (i.e. perennial) grass (usually 1–2 m tall) with very elongated, greenish or yellowish-coloured seed-heads. The main stem (i.e. rachis) of the seed-head is rounded and the relatively short bristles (mostly less than 10 mm long) are rough (i.e. scabrous).
Mission grass (Cenchrus polystachios) is a large long-lived (i.e. perennial) grass (usually 2–3 m tall) with very elongated, yellowish or brownish-coloured seed-heads. The main stem (i.e. rachis) of the seed-head is angular and the relatively long bristles (4–25 mm long) are hairy (i.e. plumose).
Deenanth grass (Cenchrus pedicellatus) is a moderately-sized short-lived (i.e. annual or perennial) grass (usually 30–150 cm tall) with elongated, pale purplish-coloured seed-heads. The main stem (i.e. rachis) of the seed-head is angular and the relatively long bristles (6–24 mm long) are hairy (i.e. plumose).
Swamp foxtail (Cenchrus purpurascens) is a moderately-sized long-lived (i.e. perennial) grass (usually 60–100 cm tall) with relatively elongated, purplish-coloured seed-heads. The main stem (i.e. rachis) of the seed-head is rounded and the relatively long bristles (15–30 mm long) are hairless (i.e. glabrous).
Elephant grass (Cenchrus purpureus) is a very large and robust long-lived (i.e. perennial) grass (1–7 m tall) with elongated, greenish or purplish-coloured seed-heads. The main stem (i.e. rachis) of the seed-head is rounded and the relatively long bristles (10–16 mm or more long) are rough or hairy (i.e. scabrous to plumose).
Feathertop (Cenchrus longisetus) is a relatively small long-lived (i.e. perennial) grass (15–100 cm tall) with relatively broad, oblong-shaped, whitish-coloured seed-heads. The main stem (i.e. rachis) of the seed-head is angular and the very long bristles (30–70 mm long) are hairy (i.e. plumose).
