St. Augustine Grass
Stenotaphrum secundatum
- St. Augustinegrass CTAHR Fact Sheet (downloadable .pdf)
Summary
- Tropical and subtropical creeping stoloniferous perennial grass
- Established by vegetative propagation (sod, sprigs, plugs)
- May take 5-6 months to form a complete cover
- Once established resists weed invasion
- Root-knot and reniform nematode susceptible
- Chinch bug is major insect pest in Hawai`i (resistant cultivars available)
- Used as a cover crop in plantations (coconuts, papaya, coffee), for erosion control, as a low quality pasture grass, and as a popular turf grass
- Moderate salt tolerance
- Very shade tolerant to shade-loving
Common Name
Its common name is St. Augustine grass (Bogdan), buffalo grass (Australia, Hawai`i, and South Pacific). It should not be confused with true buffalograss (Buchloe dactyloides). In Hawai`i it is called manienie-haole or akiaki-haole (Deputy).
Scientific Name
The scientific name is Stenotaphrum secundatum (Walter) O. Kuntze (Chen).
Cultivars
St. Augustine cultivars 'Floratine', 'Floratam' (cinch bug resistant) and 'Floralawn' (cinch bug resistant) are used for lawns in Hawai`i (Deputy). 'Roselawn' is used for soil conservation (Bogdan).
Seed Description
Seeds are oblong, about 2 mm long (Chen).
Seedling Description
No information is available in this database on this topic.
Mature Plant Description
St. Augustine grass is a stoloniferous perennial with upright or ascending stems, very branched, 10-50 cm high. Its leaves are slightly bluish, flat, blunt, glabrous, 3-15 cm long and 4-10 mm wide. Spikes are 4-10 cm long and 3-7 mm wide (Bogdan).
Temperature
St. Augustine grass is considered a pantropical species (Bogdan). It is one of the more cold/frost tolerant of the tropical and warm temperate grasses (Chen).
Origin and Geographic Distribution
St. Augustine grass is native to North America (the shores of the Atlantic) and has subsequently been distributed extensively through Central and South America, India, Australia and the Pacific, generally in coastal areas (Bogdan) (Chen).
Ecology
St. Augustine is primarily a coastal pioneer. It occurs from sea level up to 800 m. (due to cold and frost tolerance). It grows in humid areas, preferring fertile soils, but can adapt to low fertility conditions. It grows on Florida's organic sandy soils and on alkaline soils (Chen).
Water
St. Augustine grass grows in humid areas. It tolerates short term flooding and salt spray. It does not tolerate a prolonged dry season nor soils with a shallow water table. It can adapt to sandy organic soils (Florida) or alkaline soils (Chen).
Nutrients
St. Augustine grass can grow on low fertility soil and also responds well to N and P fertilization. Herbage yields are increased by adding N (Bogdan). In lawn management, either a low or high fertility regime can be used, however overfertilization (with N) promotes excessive thatch buildup and insect problems (Deputy).
Soil pH
Optimum pH for St. Augustine grass is between 6.0 and 8.5 (Deputy). pH range: 5.0-7.0 (NRCS)
Soil Type
St. Augustine grass will grow on a wide range of soils, and is naturally adapted to sandy soils (Chen).
Shade Tolerance
St. Augustine grass is shade tolerant and produces higher yields under shade intensities as low as 40% sunlight than in full sunlight. Its productivity is maintained with 40% full sunlight (Chen).
Salinity Tolerance
St. Augustine grass has good salt tolerance but avoids highly saline sea shores (Bogdan).
Herbicide Sensitivity
Deputy reports that MSMA and CMA will cause severe damage.
Life Cycle
St. Augustine grass only flowers occasionally in the wet tropics, therefore seed production is very poor. It is generally propagated vegetatively (by planting stolons). Stolons grow quickly but it may take 5-6 months to form a complete cover. Sward formation is faster under light to moderate shade. Once established, St. Augustine outcompetes weeds (Chen).
Seeding Rate
- None or very little seed is produced (Bogdan). St. Augustine grass is usually propagated vegetatively.
- Sprigging or plugging: Use well-rooted sprigs or 3-4 inch square sod plugs planted on 12-inch spacing (Deputy).
- Planting rate: 40-80 bu/ac, sprigs or stolons, maximum 3x3 ft. spacing (NRCS).
Seeding Depth
Not applicable.
Seeding Method
Not applicable.
Seeding Dates
Not applicable.
Inoculation
Not applicable.
Seed Cost
Not applicable.
Seed Availability
Difficult to obtain. None or very little seed is produced (Bogdan).
Days to Flowering
No information is available in this database on this topic. According to Chen, St. Augustine only flowers occasionally in the wet tropics.
Days to Maturity
No information is available in this database on this topic.
Seed Production
Not applicable.
Seed Storage
Not applicable.
Growth Habit
St. Augustine grass is a stoloniferous perennial, creeping extensively by means of branched rhizomes and many noded stolons (FAO).
Maximum Height
St. Augustine grass grows to a maximum height between 10-50 cm high (Bogdan).
Root System
No information is available in this database on this topic.
Establishment
- St. Augustine grass can be established by stolons, plugs or sod (Deputy).
- Sprigging or plugging: Use well-rooted sprigs or 3-4 inch square sod plugs planted on 12-inch spacing (Deputy).
- Planting rate: 40-80 bu/ac, sprigs or stolons, maximum 3x3 ft. spacing (NRCS).
Maintenance
No information is available in this database on this topic. For information about St. Augustine lawn maintenance, refer to (Deputy).
Mowing
- Lawns: refer to (Deputy)
- Grazing: St. Augustine should be closely cut or grazed to a height of about 5 cm from ground level (about every 12-14 days) (Chen) and will tolerate closer grazing (Bogdan).
Incorporation
Not applicable. Not generally used as a green manure.
Harvesting
St. Augustine grass is not generally harvested.
Equipment
No information is available in this database on this topic.
Uses
- Cover crop in plantations (coconuts, papaya, coffee)
- Erosion control
- Low quality pasture grass
- Popular turf grass
Mixtures
Reports of using a St. Augustine grass/Siratro (Macroptilium atropurpureum) mixed pasture beneath a sparse coconut plantation in Vanuatu gave annual liveweight gains of 275-400 kg/ha (Chen).
Biomass
No information is available in this database on this topic.
N Contribution
No information is available in this database on this topic.
Non-N Nutrient Contribution
No information is available in this database on this topic.
Effects on Water
No information is available in this database on this topic.
Effects on Soil
No information is available in this database on this topic.
Effects on Livestock
St. Augustine grass declines in quality through its growing season. N concentrations range between 2.6% and 2.0%. Digestibility of crude protein declines from 53% to 31%. Dry matter digestibilities decline from 60% to 50%. It is palatable when young (Chen).
Pest Effects, Insects
Deputy reports the chinch bug (Blissuus leucopterus) being the major insect pest of St. Augustine in Hawai`i. Two cultivars of St. Augustine grass, 'Floratam' and 'Floralawn' are resistant to chinch bug invasion. Other insect pests include the webworm and armyworm. High levels of N fertilizer encourage insect problems.
Pest Effects, Nematodes
St. Augustine grass is root knot and reniform nematode susceptible (personal communication, Robert Joy, NRCS Hawai`i Plant Materials Center).
Pest Effects, Diseases
Brown patch and gray leaf spot disease can be a problem for St. Augustine grass lawns (Deputy). Brown patch can occur during warm, humid weather and is promoted by excessive N applications. Gray leaf spot occurs during rainy periods and is promoted by overwatering.
Pest Effects, Weeds
No information is available in this database on this topic.
Pest Effects, Vertebrates
No information is available in this database on this topic.
Uses in the Pacific Region
In Vanuatu, St. Augustine grass-siratro (Macroptilium atropurpureum DC. Urban) pastures beneath a sparse coconut plantation gave annual liveweight gains of 275-400 kg/ha. Only 1-2 head could be sustained during the growing season under a denser stand of coconuts at a 9-m. spacing (Chen).
Uses in Hawai`i
The Hawai`i Natural Resources Conservation Service Technical Guide includes St. Augustine grass. Their specification describes St. Augustine grass as follows:
- pH range from 5.0-7.0;
- Planting rate 40-80 bu/ac (sprigs or stolons, maximum 3x3 ft. spacing),
- Medium maintenance required;
- Very good shade tolerance;
- Fair drought tolerance;
- Rainfall range of 40+ inches;
- Slow rate of establishment;
- Elevation range from 0-3000 ft.
Dr. J. DeFrank, UH Manoa, has a cover crop demonstration site using St. Augustine grass as a living mulch in papaya trials.
References
Bogdan, A.V. 1977. Tropical Pasture and Fodder Plants. Longman Inc., New York. pp.284-285.
Chen, C.P., 1992. Stenotaphrum secundatum (Walter) O. Kuntze. In: 't Mannetje, L. & Jones, R.M. (Editors): Plant Resources of South-East Asia No 4. Forages. Pudoc-DLO, Wageningen, the Netherlands. pp. 208-209.
Deputy, J., Hensley, D., Tavares, J., 1998. St. Augustinegrass TM-3. University of Hawaii at Manoa, Honolulu. 2 pp.
Evans, Dale O., Joy, Robert J., & Chia, C.L., 1988. Cover Crops for Orchards in Hawaii. Hawaii Institute of Tropical Agriculture and Human Resources, University of Hawaii at Manoa, Honolulu, Hawaii, United Stated. 16 pp.
FAO Grassland Index Web Site
USDA Natural Resources Conservation Service, Hawai`i Field Office Technical Guide, Section IV, Code 340 "Cover and Green Manure Crop" May 1992. Pacific Islands Area Field Office Technical Guide (eFOTG) - East Area
Text last updated on 9/23/02.