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Graminae
Common names
Weeping love grass (South Africa, United States), African love
grass (Australia), pasto llorón (Peru).
Description
Densely tufted perennial 90-120 cm high, with rigid narrow
leaf blades with inrolling margins. Panicle narrow with green or dark grey
spikelets up to 2 mm wide having 6 florets. It is very similar to E. chloromelas
but differs in having rigid and non-filiform branches and flat leaves (Chippendall,
1955). The foliage is exceedingly tough.
Distribution
Native of Tanzania, now throughout South Africa, and introduced
in several warm countries.
Season of growth
Spring and summer.
Altitude range
Sea-level to 3 500 m (originated near the equator in Tanzania
at 1 000-1 600 m).
Rainfall requirements
500-1 000 mm in the tropics and subtropics generally. It will
grow in rainfall as low as 300 mm if sown in basins or contour furrows
and mulched (Miller & Hafenrichter, 1958).
Drought tolerance
It is quite drought tolerant.
Soil requirements
It prefers sandy loams but will grow in a wide range of soils.
It prefers a pH of 7.0-8.5 (Miller & Hafenrichter, 1958).
Land preparation for establishment
A good seed-bed is preferred.
Sowing methods
Broadcast or drilled.
Sowing depth and cover
Do not cover over 0.5-1 cm.
Sowing time and rate
Sow late spring to late summer at 1 kg/ha broadcast or 0.25
kg in 1-m rows.
Number of seeds per kg.
Approximately 3 850 000 or 110 000 flat spikelets.
Seedling vigour
Excellent.
Vigour of growth and growth
rhythm
It starts growing early in the spring and continues until well
into the autumn.
Response to defoliation
It is best subjected to rotational grazing to maintain the
stand at moderate grazing pressure.
Grazing management
If it is sown in rows, an inter-row cultivation during the
first year will help it compete with weeds, which it will do in succeeding
years. Periodic mowing will be beneficial if stock cannot keep it eaten
close to the ground. Davidson (1964) developed a system of management based
on a heavy initial dressing of nitrogen and then annual maintenance dressings
based on nutrient removal in milk, working on 80 percent return of nitrogen
by the grazing animal and 50 percent nitrogen recovery in shoots.
Response to fire
It tolerates fire.
Dry-matter and green-matter
yields
At Stillwater, Oklahoma, United States, Pumphrey (1978) over
four years obtained an average production of dry matter over the summer
period from 1 July to 22 November of 3 178 kg/ha unfertilized, and 8 502
kg/ha fertilized with 224 kg N and 45 kg P2O5 per hectare. When fertilized
with 450 kg N, 38 kg P and 58 kg K per hectare, the mean annual yield of
E. curvula at Henderson Research Station, Zimbabwe over three years was
5 930 kg DM/ha (Rodel, 1970). At Samford, Queensland, dry-matter yields
ranged from 13 000-27 000 kg/ha per year with eight-week cutting intervals
(Strickland, 1973). Nitrogen was applied at 45 kg/ha at eight-week intervals.
The grass was not irrigated. The mean yields were approximately double
those for the four-week cutting interval. Under irrigation and with fertilization
it yielded 28 000-32 000 kg DM/ha in south-west Australia (Roberts &
Carbon, 1969).
Suitability for hay and
silage
It makes good hay if cut before it becomes too tough, and combines
well with lucerne in southern Africa.
Value as a standover or
deferred feed
It is grown for winter pasture in Florida.
Seed yield
30-225 kg/ha under good conditions. Larger seed is obtained
from rows.
Cultivars
The 'robusta' types from Argentina yielded the highest in trials
at Samford, Queensland, and the 'South African Robusta Blue' (CPI30380)
was the highest individual yielder (Strickland, 1973). 'Witbank', 'Ermelo',
'Kromarrai' and 'American Leafy' are cultivars; 'Morpa' has been released
in Oklahoma because it has better palatability and gives better animal
production (12 percent) than common weeping grass (Shoop, McIlvain &
Voight, 1976). 'Renner' was released in Texas because of better palatability
than 'Ermelo'. It remains green during drought and heat, autumn and winter
and into maturity (Dalrymple, 1978).
Main attributes
Establishes easily, persists well under grazing. A tough grass
with good cold tolerance, responds well to nitrogen, valuable in erosion
control. Good palatability.
Optimum temperature for
growth
It endures heat.
Minimum temperature for
growth
Just above freezing.
Frost tolerance
It has survived temperatures as low as freezing in the southern
Great Plains of the United States. At Samford, Queensland, E. curvula (CPI143218)
produced dry matter at the rate of 52 kg/ha per day between March and July,
during which 29 frosts were recorded (Strickland, 1973).
Palatability
The robusta types are well grazed by stock when young. Leigh
(1961b) grouped E. curvula types into groups 'curvula', 'robusta
green', 'robusta intermediate', 'robusta blue' and 'chloromelas'. The three
'robusta' types were the most palatable, 'chloromelas' varieties and E.
plana being intermediate and the 'curvula' varieties the least palatable.
Response to photoperiod
It is indifferent to day length for flowering (Evans Wardlaw
& Williams, 1964), i.e. day neutral.
Chemical analysis and
digestibility
Digestibility results at Samford showed a range from 65 percent
in spring to 49 percent in midsummer and 50 percent in mid-winter, with
crude protein from 17.5 percent in spring to 6.25 percent in midsummer
and 9.4 percent in midwinter (Strickland, 1973).
Natural habitat
Clearings in woodlands in trampled disturbed land, moist sandy
soil.
Tolerance to flooding
Not good. It will not grow on wet, seepy soils and will not
tolerate standing water.
Fertilizer requirements
It will grow on poor soils, but for high production it needs
extra nitrogen. With no nitrogen in Oklahoma, United States, forage yield
was 2 178 kg/ha, with 112 kg N/ha it yielded 8 309 kg/ha, and with 224
kg N/ha, 11 374 kg/ha. It also has a high potassium requirement and removed
3.8, 4.0 and 4.7 kg of potassium per 454 kg of forage at low, medium and
high nitrogen rates (Altom, 1978). Botha and Hamburger (1953) got significant
increases in response to nitrogen with the Ermelo strain but not to phosphorus.
A positive nitrogen/phosphorus interaction only occurred with applications
of nitrogen in excess of about 300 kg N/ha.
Compatibility with other
grasses and legumes
In the United States it is sown with Korean lespedeza.
Genetics and reproduction
2n=20, 40, 50, 80 (Fedorov, 1974). It is an obligate apomict
(Brown & Emery, 1958).
Seed production and harvesting
This grass seeds heavily. It is harvested in early summer and
again later in summer with a header-harvester or a hand sickle when one-third
of the head has turned brown. Try to prevent scattering.
Economics
Eragrostis curvula has been used successfully for oversowing
the broad intermontane plains or altiplanos of the arid to semi-arid Puna
proper in the province of Juyjuy in northern Argentina at 3 000 m elevation.
The seed is sown in listed furrows at 2 kg/ha and covered with sheep manure.
It takes 20-25 days to germinate. The seed is Tanganyika-type E. curvula
grown locally in Buenos Aires (Tothill, 1978). E. curvula is one of the
highest producing grasses in summer rainfall areas of temperate and cool
subtropical areas of South Africa (Strickland, 1973).
Animal production
At Henderson Research Station, Zimbabwe, when fertilized at
270 kg N/ha and 35 kg P/ha per year and grazed over two summers by heifers
at the rate of 12.4 per hectare, the mean maximum live-weight gain from
E. curvula was 550 kg/ha (Rodel, 1970). At Deniliquin, New South Wales,
irrigated E. curvula yielded 4 321 kg/ha unfertilized and 12 985 kg/ha
per year fertilized with 480 kg/ha N (Squires & Myers, 1970). Stocked
at 53 sheep per hectare over 130 days it gave a live-weight gain of almost
3 kg/ha; but at 70 sheep per hectare a live- weight loss of almost 4 kg
per animal occurred.
In Oklahoma, Morpa weeping love grass showed steer gains of 1 kg per
day during May and June, and 0.71 kg per day during July and August at
a stocking rate of 1.5 steers per hectare during a 278-day grazing year
(Pumphrey, 1978). Over a three-year period, Hereford steers showed 13 percent
more live-weight gain (per animal) than those grazing the least palatable
selections, and 12 percent more than those grazing common love grass, also
of low palatability (Voight et al., 1970).
Further reading
Altom, 1978.
Value for erosion control
It is widely used in Kenya, Sri Lanka and the United States
for stabilization of terraces, water discharge areas and banks of earth
tanks. In Japan it has helped stabilize mountain slopes for at least three
years (Endo, 1978).
Tolerance to salinity
It is very tolerant of salinity and seed germinates well under
high levels of soil sodium (Ryan, Miyamoto & Stroehlein, 1975). In
Western Australia, E. curvula (CPI14369) was moderately tolerant (Rogers
& Bailey, 1963).
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