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Graminae
Synonyms
Amphilophis pertusa (L.) Stapf; Andropogon pertusus (L.) Willd.
Common names
Seymour grass, hurricane grass (Africa), camagueyana (Cuba), Indian blue grass
(Australia), Barbados sour grass.
Description
Tufted perennial 30-70 cm high, rarely stoloniferous. Sessile spikelets finely hairy on
the back and sides; pedicelled spikelets, usually with one pit but occasionally with three
or none (Napper, 1965). Very close to Bothriochloa insculpta, the latter having a glabrous
lower glume and one to three pits. It is smaller with slightly smaller panicles and
shorter spikelets. In some specimens of B. pertusa the culms creep about the surface of
the soil and root at the nodes (Bor, 1960). Roots penetrate to 55 cm with production of 6
356 kg/ha of root on alluvial soil at Varanasi, India (Ramam, 1970). Rhizomes constitute
80 percent of the total below-ground dry matter.
Distribution
Kenya, Uganda, southern and north-eastern tropical Africa, Southeast Asia, Caribbean
archipelago.
Altitude range
Sea-level to 2 100 m in India.
Rainfall requirements
In the areas of 500-1 375 mm in India (Whyte, 1968) and in the dry zone of Burma with
600-1 000 mm of rainfall, up to 1 800 mm in Timor.
Drought tolerance
Withstands short dry spells. Shankarnarayan (1963) lists it as a perennial
drought-evading plant.
Soil requirements
It will grow on poor soils and succeeds H. rufa on poor soils in Panama. It is common
on the black cotton soils of India (Chinnamani, 1968) and Timor (Whyte, 1968) and also
grows on a variety of soils from coarse to fine- textured with a pH range from pH 5.8-7.5
and on lateritic soils (Whyte, 1968).
Ability to spread naturally
It is a vigorous weed in the pastures of the United States Virgin Islands, invading
Guinea grass, molasses grass and Bermuda grass (Oakes, 1968).
Land preparation for establishment
A fine seed-bed is preferable, but it will establish slowly in a rough seed-bed.
Sowing methods
Broadcast the seed on the surface of the soil and roll or cover lightly.
Sowing time and rate
Sow in early summer at 1.5 kg/ha.
Number of seeds per kg.
1 210 000 pure seed (Bogdan & Pratt, 1967).
Response to defoliation
It withstands heavy grazing and trampling (Bor, 1960). It represents the first stage in
degradation of the Sehima/Dichanthium cover in India (Dabadghao & Shankarnarayan,
1973).
Response to fire
It survives fire (Whyte, 1968).
Dry-matter and green-matter yields
In Cuba, Pérez Infante (1970) obtained average annual yields of 15 000 kg DM/ha, of
which 40 percent was produced in the dry season under sprinkler irrigation (Bogdan, 1977).
Suitability for hay and silage
Silage was made successfully in pits 7.62 x 0.45 x 1.83 m deep in India from 1940-45
from this grass (Whyte, 1964). It makes useful hay (Bor, 1960).
Cultivars
In Maharashtra State, India, Oke (1971) recommends cv. Ghana Marvel 20 which gives
40-100 percent more dry matter than the local strain. The Queensland Department of Primary
Industries is evaluating six types of this species.
Diseases
There are no major diseases.
Main attributes
It will stand up to trampling and constant grazing.
Main deficiencies
Tends to become a weed.
Ability to compete with weeds
Excellent. It can invade also Guinea, molasses and Bermuda grasses, although can be
suppressed by pangola grass (Oakes, 1968).
Pests
There are no major pests.
Palatability
It is quite palatable.
Natural habitat
Grassland on clay soils and open woodland.
Tolerance to flooding
Whyte (1964) lists it as an associated species in loamy soils subject to waterlogging
at Ballasar colony, North Gujarat, India.
Genetics and reproduction
2n=40, 60 (Fedorov, 1974). In India it behaves both as an apomict and also undergoes
sexual reproduction (Gupta, 1969-70)
Seed production and harvesting
The seed is a hairy spikelet with an attached joint and pedicel.
Economics
A bad weed of pastures in the Virgin Islands (Oakes, 1968). It is low- yielding used
for fodder, hay and mulching in India. Considered one of the better grasses in Barbados,
Jamaica, Uganda and India.
Animal production
No figures have been found.
Further reading
Oakes, 1968; Pérez Infante, 1970; Rao, 1970.
Value for erosion control
It has been recommended for reseeding eroded land in India and shows promise for
erosion control in central Queensland. It is a good grass for revegetating spoil from
central Queensland coal mines.
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