Seashore paspalum (Paspalum vaginatum) use on golf courses has increased as a result of improved breeding and increased environmental concerns, including the need for a more salt tolerant grass species. This need is, in part, the result of poor soil and water quality associated with coastal regions and islands where the use of saline, recycled, or reclaimed irrigation water and/or the presence of saline, sodic, or saline/sodic soils are present. Seashore paspalum is indigenous to tropical and subtropical regions where it evolved on coastal sand dunes.
Seashore Paspalum Cultivar Development
Seashore paspalum is a warm season, stoloniferous perennial grass which tolerates saline conditions (up to 20,000 ppm) after established, is more cold tolerant, and requires up to 50% less water for irrigation than bermudagrass. In addition, the leaves of seashore paspalum are waxy and generally coarser than common bermudagrass, although when mowed regularly and at low heights (<0.75-inches) prodcuces a dense turf with an extensive and fibrous root system (see picture above). The varieties of seashore paspalulm currently available for golf courses include:
- Sea Dwarf: The only dwarf cultivar. Fine textured and tolerates 1/8 to 4-inch mowing heights. Ideal for greens, tees, and fairways
- Aloha: Fine-medium textured and tolerates 1/8 to 4-inch mowing heights
- SeaGreen: Fine textured cultivar adapted to high salinity conditions. Used primarily on tees and fairways.
- SeaIsle1: High salt tolerance and suitable for tees, fairways and roughs
- SeaIsle-2000: Exhibits a dark green color and is ideal for golf course greens, tees, fairways and roughs.
- SeaIsle Supreme: The most recent cultivar developed. Tolerates 1/8 to 3-inch mowing heights. Can be maintained with irrigation water containing 6,500 ppm dissolved salts.
Management and Cultural Requirements
In general, the management recommendations for seashore paspalum include:
- Mowing heights ranging from <1/8 to 4-inches depending upon cultivar
- Irrigate deep and infrequently with low quality, reclaimed, recycled, or brackish water
- Apply ~ 4 lb N/M/yr depending upon soil type, irrigation frequency, mowing height, and cultivar
- Maintain adequate P, K, Ca, Mg and minor nutrients
Cultural practices which maximize growth and development include frequent, moderate topdressing and regular core cultivation and verticutting in an effort to manage thatch. Moderate to aggressive use of topdressing will promote stolon growth, improving plant health and promoting turf recovery. General limitations of seashore paspalum include:
- Susceptible to brown patch (Rhizoctonia solani), pythium blight (Pythium spp.), particularly under high N fertility
- Susceptible to sod webworm
- Limited herbicide tolerance
- Requires fresh water for establishment, and regular root-zone leaching to maintain tolerable salt levels
Nutrition
Optimum fertility requirements for seashore paspalum continue to evolve. Currently, nitrogen requirements are rather low (3-5 lbs N/M/yr). Too high N fertility can lead to increased scalping and disease pressure. The correct balance of tissue Ca: Mg (2 or 3:1) will prmote optimum turf color and adequate Mn and Zn will activate seashore paspalum salt tolerance mechanisms. The use of Proven Foliar™ fertilizers remains the most efficient method of supplying these nutrients and maintaining them in the optimum range.
Proven Foliar™ and Granular Fertilizers
Grigg Brothers® manufactures fertilizers designed to promote optimum plant health based on turfgrass nutrient requirements. Proven Foliar™ fertilizers are designed for efficiency, performance, and compatibility. The products also increase a turf manager's control over nutrient availability and nitrogen release.
One Proven Foliar™ products have been specifically designed for seashore paspalum management:
- Low N Plus™ (1-6-12 plus micronutrients)
- Kelplex™ (1-2-2) 75% Ascophyllum modosum
Soil Specialty Products
- Bio Blend™
- Carboplex™
- Calcium Complex (12%)™
Granular (advanced protein technology)
Grigg Brothers® granular protein technology includes kelp extract which contain cytokinins, humic acid, and glycoproteins for stimulating root growth.
- Seven Iron (7-7-7 + Ca, S, and micros)
- Endurance (8-4-16 + Ca, S, and micros)
- CK (Ca derived from CaCO3)
- SK Balance (Ca derived from CaSO42-) (0-0-24 + 18% Ca and 8% S)
| Optimum Management Strategies Include: |
- Apply 3-5 lbs N/M/yr depending on soil type, irrigation frequency, and cultivar
- Irrigate deep and infrequently with low quality, reclaimed, recycled, or brackish water
- Topdress moderate-aggressively
- Maintain adequate P, K, Ca, Mg and minor nutrients
- Utilize naturally occurring chelated technology
|
Research Objectives
Determine the percent of nutrients absorbed after application of a Proven Foliar™ program, providing a better understanding of the efficiency and performance of those selected fertilizers. Low N Plus™ (1-6-12 plus B, Co, Cu, Fe, Mn, Mo, and Zn), Sili-Kal B™ (8-0-4) plus B, 10% Ca, and Si, Iron Combo Chelate (1-0-2 plus S, Cu, Fe, Mn, and Zn), and Mg Chelate (5% Mg) were applied to SeaIsle-2000 seashore paspaplum and mowed at ¼".
Results
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Programs
Grow-In
- Use best quality irrigation water
- Preplant 700 lb/A Seven Iron™ and 250 lbs/A CK-Balance or SK-Balance
- Apply 350 lbs/A Seven Iron™ every 10 days until established
- Supplement with 4 oz NutraGreen™ and 4 oz PK Plus® per 1000 ft2 weekly for 2 months until maturity
General Maintenance
- Seven Iron™ (8 lb/A) during peak growth and in conjunction with core aerification
- CK-Balance or SK-Balance for Ca and K fertility, and as a tool prior to flushing greens of excess Na.
- Apply 6 oz Low N Plus™, 6 oz PK Plus®, 3 oz Ultraplex®, and 2 oz Kelplex™ rotate every other spray with 4 oz Sili-Kal B™ per 1000 ft2 added to the base program
