Graminae

Synonyms

Panicum colonum L.

Common names

Awnless barnyard grass (Australia), jungle rice (United States), grama de ague (Cuba), pasto colorado (Peru), azz (Mauritania).

Description

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).

Distribution

Widely spread in tropical Africa, Asia and Australia.

Season of growth

Summer.

Altitude range

Sea-level to 1 800 m.

Rainfall requirements

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.

Soil requirements

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 rhythm

In the Sahel it flowers in August and has dried off by February (Boudet & Duverger, 1961).

Suitability for hay and silage

It makes very palatable hay.

Palatability

Extremely palatable.

Natural habitat

Swampy places and seasonally flooded grassland.

Genetics and reproduction

2n=36, 48, 54, 72 (Fedorov, 1974).

Economics

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.

Animal production

No figures have been cited but it is a valuable short season grazing and hay grass throughout the tropical and subtropical world.