Bahia - Turf Grass

Scientific name(s):

Paspalum notatum

Characteristics:

A hard-wearing, coarse-textured grass with soft leaves. It is used in some low maintenance situations and at airports. The grass is slow to establish from seed but once established, it out-competes other more desirable turf species due to its robust root system and dense mat of stolons and rhizomes. In southern Queensland, bahia grass is the major perennial grass weed species in parks and urban open space areas, where it requires frequent mowing during summer to remove the numerous seed heads up to 60 cm tall. Bahia grass shows poor shade tolerance, and is damaged by a number of herbicides safe to use on other warm-season turf species.

Strengths

• Adapted to a wide range of soil types Tolerates acid/low fertility soils
• Fair shade tolerance
• Good drought tolerance
• Few pest or disease problems
• Tolerant of close grazing and traffic wear Suppresses weeds once established Responds well to nitrogen

Limitations

• Slow rate of establishment
• Seedlings susceptible to phenoxy herbicides Relatively unpalatable once mature
• Can become sod-bound with time
• Not suitable for high pH soils (yellowing of leaves) Difficult to mow
• Poor winter growth and feed quality
• Difficult to maintain legume in pasture
• Potential weed on fertile soils

Plant description

• Plant: A dense mat-forming perennial grass, with a deep, strong root system. Several distinct types of bahia grass have become naturalised in Australia.
• Stems: Thick, fibrous stems (to >5 mm diameter) with short internodes. Stems held flush with the soil by deep fibrous roots.
• Leaves: Leaves arise from short, upright shoots arising from the nodes. Leaf blades, which may be hairy or hairless, are mostly 4 - 8mm wide and 20-30cm long when mature. The leaf sheaths of the lower leaves of the shoot are usually white with a distinctive purplish coloured tinge.
• Seedhead: Usually comprises two “arms” of a “Y”, and borne above the foliage on erect stems about 50cm tall.
• Seeds: Light brown in colour, flat on one side, rounded on the other,
• ‘Argentine’/'Competidor’: 3.5mm long x 2.5mm wide, about 300,000 seeds/kg’Pensacola’: 2.5mm long x 2mm wide, about 500,000 seeds/kg.
• Pasture type and use: Used as permanent forage for intensively grazed pastures and as a stable drought-resistant, ground cover/soil binder, particularly in traffic and shaded areas. More suitable for beef than for milk production. Naturalised in much of the subtropics and tropics, and often considered as a weed.

Where it grows

• Rainfall: While bahia grass will grow over a wide range of rainfall conditions, it should only be sown in areas where its good survival and retention of ground cover under drought conditions are an advantage i.e. areas with an annual rainfall between about 700 and 1200mm.
• Soils: Bahia grass grows best on fertile, well-drained lighter acid soils, but will grow on less fertile and clay soils. It is not well-adapted to alkaline soils.
• Temperature: Little growth occurs in the cooler months. Tops are burnt off by frost, but growth resumes with the onset of warmer weather in spring.
• Establishment: Companion species
• Grasses: Normally not sown with other grasses.
• Legumes: Bahia grass is too competitive to form a productive association with any commercial legumes, except white clover which grows in the cooler months.
• Sowing/planting rates as single species: 2 - 5kg/ha
• Sowing/planting rates in mixtures: Not normally sown in mixtures.
• Sowing time: Seedlings develop slowly, so it is best to sow as early as possible once there is little likelihood of frost and when there is a good chance of follow-up moisture.
• Inoculation: Not applicable. Fertiliser. While bahia grass survives in fairly infertile soil, it performs best if sown with 200 - 400kg/ha superphosphate.
• Management: Maintenance fertliser. Moderate soil phosphorus levels should be maintained with periodic applications of phosphatic fertiliser. Regular applications of nitrogenous fertiliser in association with intensive grazing help to maintain a productive stand.
• Grazing/cutting: Bahia grass should be grazed or cut regularly.

• Bahia Grass on a Golf Course

   

  Seed production: Flowering commences in early/mid-summer. Seed ripens progressively over the summer and at no time is all the seed mature. It can be combine-harvested in a single pass, or harvested over a number of passes with a beater or stripper to maximise yields. Commercial seed yields average 60-100 kg/ha, but can be higher when good production and harvesting practices are used. Most bahia grass seed is imported.

• Ability to spread: Bahia grass spreads slowly but surely. Poor seedling competitiveness limits spread, but once plants are established, they spread strongly by virtue of the stout prostrate runners, and strong root system. Viable seed is spread readily in animal dung.
• Weed potential: Many farmers consider it a weed in pastures due to its incompatibility with most other species, and low palatability when more mature.