Panicum colonum L.
Awnless barnyard grass (Australia), jungle rice (United States),
grama de ague (Cuba), pasto colorado (Peru), azz (Mauritania).
A tufted annual up to 60 mm high with geniculate culms. Panicle
erect, 5-13 cm high, racemes rather distant with crowded, green or purplish
apiculate spikelets 2.5-3 mm long. Ligule absent (Henty, 1969).
Widely spread in tropical Africa, Asia and Australia.
Season of growth
Sea-level to 1 800 m.
It grows in environments ranging from 400 mm to about 1 200
mm. In the arid areas it grows in ponds and swamps while the water lasts,
and usually seeds before it dies.
It grows in a fairly wide range of soils, but is most common
in loams, silts and clays in low places.
Tolerance to herbicides
If control is needed, a pre-emergence spray of 2,4-D sodium
salt at 4.5 kg/ha of an 850 g AI/kg product (e.g. Hormicide) can be used.
No wetting agent is required. Use a minimum of 340 litres of water per
hectare. This gives short-term protection. For long-term control use trifluralin
at 2.8 l/ha of a 400 g AI product (e.g. Treflan E.C.). Seedlings can be
killed by paraquat at 1.4 l/ha of a 200 g AI/l product (e.g. Gramoxone)
plus surfactant at 250 ml per 200 litres water (Tilley, 1977).
Vigour of growth and growth
In the Sahel it flowers in August and has dried off by February
(Boudet & Duverger, 1961).
Suitability for hay and
It makes very palatable hay.
Swampy places and seasonally flooded grassland.
Genetics and reproduction
2n=36, 48, 54, 72 (Fedorov, 1974).
It is a valuable grazing plant in its short season of growth.
The seed is eaten by humans in times of stress. It can be an important
weed of rice.
No figures have been cited but it is a valuable short season
grazing and hay grass throughout the tropical and subtropical world.