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Graminae
Common names
Bahia grass (United States), jengi brillo (Costa Rica), batatais (Brazil), Paraguay
paspalum (Zimbabwe), tejona (Cuba).
Description
A low-growing perennial spreading by short, stout, woody runners and by seed. The
runners have many large, fibrous roots which form dense, tough sods, even on drought-prone
sandy soils. The leaf-blades are generally hairy on the margins and less than 1 cm wide.
It seeds prolifically during the summer, the seed stalks 30-75 cm high, usually with two
(sometimes three) racemes, each about 6 cm long. Seeds oval, yellowish-green, glossy and 3
mm in diameter (Wheeler, 1950).
Distribution
It originated in South America and is widespread in the southern United States, Central
and South America. Introduced into Africa and Australia.
Season of growth
Spring, summer and autumn.
Altitude range
Sea-level to 2 000 m (Anderson, 1969).
Rainfall requirements
It needs a moderate to high subtropical rainfall, with a minimum of about 750 mm per
year. Mean 1 500 mm + 586 (Russell & Webb, 1976).
Drought tolerance
Because of its deep root system it has good drought tolerance.
Soil requirements
It can adapt to a wide range of soils, but is best suited to sandy soils.
Ability to spread naturally
It spreads rapidly by short stolons and seeds.
Land preparation for establishment
A fully cultivated fine seed-bed is required.
Sowing methods
The seed is drilled into a fine seed-bed and rolled. Seed is also spread readily in
animal dung and will germinate therefrom. Sods may also be laid.
Sowing depth and cover
Not deeper than 1 cm, rolled to cover.
Sowing time and rate
Drill seed in the spring, at 2-5 kg/ha.
Number of seeds per kg.
550 000 (Queensland), 330 000 (United States).
Seed treatment before planting
Hammer milling improves seed handling and germination; moistening with KNO3 solution at
25-35°C also helps germination.
Tolerance to herbicides
No records have been found.
Seedling vigour
It is not vigorous and can be subject to weed competition, hence the need for a fine,
clean seed-bed.
Vigour of growth and growth rhythm
After a slow start it grows rapidly when established and fertilized. It produces little
feed during the winter.
Response to defoliation
Most of the forage of Bahia grass sods lies near the soil surface so it should be
grazed closely and frequently to obtain the best quality material. Six-week cutting
intervals were better than 2-, 3- or 4-week intervals (Beaty, Stanley & Powell, 1968).
Grazing management
Once established, Bahia grass can be grazed heavily to near soil level. It should be
fertilized at up to 224 kg N/ha per year. Frequent defoliation over 24 months had little
effect on the sward (Beaty, Brown & Morris, 1970). Cutting at six-week intervals gave
the best yield and nutritive value in Brazil (Prates, 1977). In the early establishment
period, mow the grass every three to four weeks to suppress weeds. Top-dress with nitrogen
at 35 kg/ha during the first year, then increase as necessary. In Georgia, United States,
550 kg/ha of a 5:10:15 NPK mixture plus 110 kg N/ha is usually applied annually.
Response to fire
Winter burning is sometimes practiced in the United States to get rid of dead litter.
If the litter cover is light little harm is done, but if litter is abundant, such as after
a seed harvest, damage can result (Stephens & Marchant, 1960).
Dry-matter and green-matter yields
In Georgia, United States, yields of air-dried material varied from 5 947-7 240 kg/ha
over a four-year period with five different cultivars (Stephens & Marchant, 1960). At
Howard south-eastern Queensland, under a 1 075 mm summer-dominant rainfall, fully
fertilized, it yielded a three-year mean of 6 859 kg DM/ha with CPI 9073 introduction
(Evans, 1967a).
Suitability for hay and silage
It proved unsuitable for silage in Panama (Medling, 1972). It is not a very suitable
hay plant because of its low yield, and it is hard to mow. If well fertilized and vigorous
it can make useful hay.
Value as a standover or deferred feed
It is not very useful because of its coarseness.
Toxicity
No major toxicity has been reported. In some strains which are susceptible to paspalum
ergot there may be slight toxicity.
Seed yield
110-350 kg/ha. 112 kg N/ha early in the season will improve seed yields (Stephens &
Marchant, 1960).
Cultivars
described above.
Introduced to the United States from Paraguay. The leafblades are hairier and
narrower than 'Common Bahia'. It seeds heavily and the seed is of good quality. It is very
winter-hardy, but is too tough for grazing from midsummer to autumn. It is palatable in
spring and summer. It is a lawn grass.
narrow-leaved like 'Paraguay', but less hairy. The seeds are smaller than those of
either 'Common' or 'Paraguay', and more seeds are produced per head. It seeds heavily, but
the seed shatters badly. The seed germinates well and the grass establishes a sod quickly.
It is fairly frost tolerant and growth starts early in the spring. It is fairly resistant
to ergot.
a medium broad-leaf type which makes a rapid and abundant growth and is more frost
resistant than cv. Common and cv. Paraguay. It does not make early spring growth, but
grows well in later summer and autumn.
not used much. Cultivar Wallace gives low production and cv. Tampa is easily killed
by frost.
hybrid which has outyielded cv. Pensacola at Tifton, Georgia, United States.
the main cultivar used at the Henderson Research Station, Zimbabwe, but several
accessions promise to offer alternatives (Mills & Boultwood, 1978).
- There is also a var. saurae Parodi.
Diseases
Argentine Bahia grass is attacked by paspalum ergot (Claviceps paspali).
Helminthosporium micropus sometimes causes damage.
Main attributes
Bahia grass is a deep-rooted perennial which stands heavy grazing and forms a dense
turf.
Main deficiencies
It is relatively unpalatable to cattle (but the least palatable cultivars give the best
live-weight gains), it suffers in periods of drought and does not produce a large volume
of herbage (Harker, 1962). As a lawn grass it is often difficult to mow.
Optimum temperature for growth
25-30°C. Mean 20.2°C + 3.2 (Russell & Webb, 1976).
Minimum temperature for growth
Mean temperature of the coldest month 7.8°C + 5.3 (Russell & Webb, 1976).I
Frost tolerance
Good; 90 percent survival from the first winter in Queensland on the Darling Downs
(Jones, 1969). It was eliminated by a temperature of -12°C in North Carolina, United
States.
Latitudinal limits
About 25°N and 30°S (Russell & Webb, 1976).
Response to light
It does not grow well in shade.
Ability to compete with weeds
It can become weed infested early in its growth but when established it forms a dense
sod, making it a useful lawn grass (Chippendall & Crook, 1976). It can itself become a
weed.
Maximum germination and quality
required for sale
60 percent germinable seed, 60 percent purity in Queensland.
Pests
Cultivar Paraguay 22 is resistant to the sting nematode (Belonolaimus longicaudatus)
which affects cv. Pensacola and Hemarthria altissima (Boyd & Perry, 1972).
Palatability
It is reasonably palatable in spring and summer, but is too coarse from midsummer to
autumn (Burton, 1945). In the West Indies, Motta (1956) reported that it lacked
palatability in trials held between 1948 and 1954. It is not as palatable as Cynodon
aethiopicus.
Response to photoperiod
It is a long-day plant (Evans, Wardlaw & Williams, 1964).
Chemical analysis and digestibility
In Costa Rica, analyses of material at floral initiation revealed 6.75 percent crude
protein, 28.25 percent crude fibre, 43.32 percent nitrogen-free extract, 1.29 percent
ether extract and 10.39 percent ash in the dry matter on a 10 percent moisture basis
(Gonzalez & Pacheco, 1970). In Laos, Chavancy (1951) recorded 13 percent crude protein
and 34.5 percent crude fibre in the dry matter of fresh material in late bloom.
Tolerance to flooding
It is fairly tolerant of flooding. In New South Wales, Australia, it was submerged for
25 days, but it was non-productive during this time (Colman & Wilson, 1960).
Fertilizer requirements
On Leon fine sand in Florida it responds well up to 224 kg N/ha per year (Beaty, Powell
& Etheredge, 1963; Blue, 1970). On these poor sandy soils it fails to grow without
10-12 kg/ha of copper (as copper oxide or sulphate) because of soil deficiency (Hodges,
Jones & Kirk, 1958). One or two early applications of 25-30 kg N/ha will hasten
development. CSIRO workers in Queensland (Weier, 1976) have shown it has an active
nitrogenase system and, over a growing season of 12 weeks, P. notatum fixed nitrogen at
the rate of 4 kg N/ha per day. Schegel (1978) associates this with Azotobacter paspali.
Recovery rate of added fertilizer nitrogen increased yearly to the sixth year when it
reached about 60 percent at 112 kg/ha and 70 percent at an application rate of 224 kg/ha
(Blue, 1970).0
Compatibility with other grasses and
legumes
In the transition zone between temperate and subtropical species, Bahia grass tends to
invade temperate species (Hoveland, Hasland & Rodriguez-Kabana, 1977). White clover
and crimson clover can grow with it, if well fertilized. In Zimbabwe, Clatworthy (1970)
grew it successfully in combination with Trifolium semipilosum and Lotononis bainesii.
Genetics and reproduction
2n=20 (sexual), 2=40 (apomictic) (Bashaw, Hovin & Holt, 1970).
Seed production and harvesting
Bahia grass ripens progressively over the summer in the United States and at no time is
all the seed mature. Thus, a series of harvests with a beater or stripper gives the
highest yields. Combine harvesting can be carried out, but yields are reduced. Seed should
be dried thoroughly immediately after harvest.
Economics
Bahia grass has resistance to internal root nematodes (root-knot and meadow nematodes)
which are serious pests of tomatoes. In the United States, Bahia grass is often used as a
ley in a four-year rotation to reduce the damage to tomatoes (Stephens & Marchant,
1960). The grass is easily ploughed out.
Animal production
In Georgia, cv. Argentine produced 405 kg beef per hectare, cv. Pensacola 439 kg/ha and
'Tifhi-1' 514 kg/ha per year (Johnson & Gurley, 1960). Stocking rates over a four-year
period with five cultivars averaged about five beasts per hectare (Stephens &
Marchant, 1960).
Further reading
Burton, 1945; Stephens & Marchant, 1960.
Dormancy
Germination is usually slow. It improves with up to three years' storage and then
declines. Dormancy can be broken by treatment with sulphuric acid (Burton, 1945) and by
hammer milling.
Value for erosion control
Bahia grass is often used to stabilize terraces against erosion.
Tolerance to salinity
No record has been found.
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