Urochloa brachyura is an annual grass that grows 120cm tall. The culms are erect or ascending with swollen nodes and internodes and green to reddish in colour.
It can be easily identified by its narrow leaves with a greenish-blue hue and its spikelets arranged in an elongated panicle with a tail-like appearance.
Urochloa brachyura Classification
- Domain: Eukaryota
- Kingdom: Plantae
- Phylum: Tracheophyta
- Subphylum: Angiospermae
- Class: Monocotyledonae
- Order: Poales
- Family: Poaceae
- Genus: Urochloa
- Species: Urochloa brachyura
- Common Names: Signal grass
Nativity and Distribution
Annual tail grass is native to East and South Africa. It is mostly found in:
- Ethiopia
- Kenya
- Tanzania
- Namibia
- Botswana
- Zimbabwe
- Angola
- Zambia
- South Africa
Physical Characteristics
- Leaves: Alternate, lanceolate, glabrous or slightly pubescent, 3-30 cm long
- Fruits: Elongated, flattened, and tan to light brown
- Stems: Erect or ascending culms. Can reach a height of 1.2m
- Flowers: Inflorescence of 2-10 racemes
- Roots: Fibrous root system
Urochloa brachyura is an annual grass that can grow up to 1.2m tall. It is easily recognizable by its narrow leaf blades with a greenish-blue hue and its spikelets arranged in an elongated panicle giving it a tail-like appearance.
Culms are upright or geniculately ascending with nodes and extended internodes. The stems can be glabrous or slightly pubescent and are greenish with reddish hues.
The leaves are alternate, narrow, and linear in shape, about 0.3-1.6 cm wide and 3-30cm long. They emerge from the numerous nodes along the stem creating a bushy appearance.
The inflorescence is arranged on an open panicle containing drooping multiple spikelets 3.5-6.0mm long. The elongated panicle resembles a tail, hence its name, “Tail Grass”. Flowering occurs between October and April.
The seeds are tan to light brown, elliptical to slightly ovate in shape, smooth or wrinkled, and may have awns or bristles attached to them. Each seed is enclosed in a small papery husk that protects it until germination.
Reproduction, Dispersal, and Life Cycle
- Life Cycle: Annual
- Seeds: It’s a prolific seed producer
- Climate: Tropical climate
- Dispersal: Wind, water, and animals
U. brachyura behaves as an annual weed and reproduces by seed and rhizomes. The seeds are dispersed by wind, water, and animals over long distances. They germinate on the soil surface or in shallow soil (to a depth of 0.5-1 cm).
The grass also reproduces by rhizomes, where new shoots and roots emerge from the root network to form new plants.
Similar Plants
- Urochloa trichopus
- Urochloa oligotricha
Uses
- It is used as forage for grazing animals.
- The grass can be used as a cover crop to control weeds and prevent soil erosion.
Impact on Farms and Environment
Annual tail grass can provide nutritious forage for livestock in areas where other options may be limited.
However, due to its dual reproduction methods, it can become invasive and outcompete native vegetation. In Western Australia, it has been declared a pest and prohibited for use, except for research and other highly secure institutions.
As a weed of the woodlands and grasslands, it can alter native biodiversity, causing long-term environmental degradation.
Control
- Cultural control: Grazing
- Mechanical control: Tillage
Controlled grazing can limit the spread of U. brachyura on grasslands and other open areas. However, if it invades agricultural lands, repeated tillage may be required to remove the extensive root systems and eradicate the grass.
Due to its importance as a forage grass in pastoral communities, herbicides are generally not considered for removal. However, if you discover an infestation on your farm or landscape, consider consulting an expert for the right product to apply.
Lead Editor for Insight Weeds.