Earl Elsner, GA Seed Dev. Comm.
Wayne Hanna, USDA/ARS
TifEagle was bred, evaluated, developed and released by Wayne Hanna at the Coastal Plain Experiment Station, Tifton, GA. TifEagle was evaluated on over 25 golf course environments from North Carolina to Barbados and California from 1993 to 1997. The data collected from these sites show that TifEagle is capable of producing a premium quality putting surface meeting the highest golfing standards. TifEagle putting greens have been overseeded with Poa trivialis since 1994. High quality, uniform overseeded putting surfaces are routinely obtained with a minimum loss of play.
Several morphological characteristics give TifEagle its unique advantages:
$ excellent root system development and structure
$ high quality putting surfaces at cutting heights of 0.125" and lower
$ rhizomatous rather than stoloniferous growth habit
$ superior color under cool conditions
$ tolerance to verticutting
$ rapid regrowth from mechanical injury
The rhizominous growth habit with appropriate topdressing and verticutting provides an excellent seedbed for uniform overseed establishment. TifEagle's tolerance to close mowing gives the superintendent an excellent tool to manage and control spring transition.
TifEagle will produce higher quality putting surfaces than Tifdwarf, but also requires more intensive management. Thus, TifEagle may not be the best variety for all golf green situations. Research has shown that inadequate maintenance of TifEagle will result in thatchy and inferior putting surfaces. Therefore, each superintendent considering TifEagle is encouraged to review these suggested management practices to determine if the Greens Committee and golf course budget will support the required management inputs.
The authors express sincere appreciation to researchers and golf course superintendents who evaluated TifEagle, responded to questionnaires or otherwise assisted in the development of these management practices. Special thanks go to Superintendents Darren Davis, Gerry Hillier, Ralph Hinz, Rodney Lingle and William Smith; turf research and extension scientists Monica Elliott, Beth Guertal, Gil Landry and Bryan Unruh; PGA agronomist Johnathan Scott and USGA agronomists John Foy, Chris Hartwiger and Patrick O'Brien.
Suggested Management Practices
I. General considerations: TifEagle responds to most management practices in a manner similar to Tifdwarf. However, as a result of its distinct genetic background, turf density and ability to tolerate extremely low heights of cut, several suggested management practices are specific to TifEagle. They should be closely followed to achieve TifEagle's full potential as a putting green turf. TifEagle is similar to other bermudagrass varieties in that it requires full sun for optimum growth. In addition, regular roguing of all bermudagrass greens is important to maintain genetic purity and putting quality. It is especially important to rogue off-types before overseeding.
TifEagle is recommended for closely mowed areas ONLY. Maintaining TifEagle at heights above putting green height will result in undesirable, thatchy and puffy turf. Thus, TifEagle is not recommended for collars. A suggested alternative is to use Certified Tifway or Tift 94 sod. Use sod grown and maintained at 3/8-1/2". Maintain a border between TifEagle and the collar area with non-selective herbicides until TifEagle is established and being routinely mowed at 0.125 ".
II. Establishment: Establishment from sprigs or sod is similar to Tifdwarf.
1. Sprigbed preparation:The surface should be as smooth and firm as possible. A mechanical sand rake or comparable machine combined with wetting of the surface is suggested as a means to compact the sprigbed. Good surface and internal root zone drainage is necessary. The sprigbed should be fumigated (2 lbs methyl bromide/100 sq. ft.) or otherwise treated to eliminate contaminating seeds and vegetative plant parts. Good root zone moisture should be established before planting.
2. Planting rate is similar to Tifdwarf.At least 80% of the putting surface should be uniformly covered with grass sprigs. Voids larger than 3 inches increase grow-in time. Sprigs should be cut into surface and firmed with a roller.
3. Water requirements are similar to Tifdwarf.Irrigate immediately after distributing and cutting in sprigs. Any drying of sprigs will reduce survivability and increase grow-in time. Be prepared to hand water immediately after planting each section of a green. Irrigate frequently during daytime until rooted, keeping soil surface moist, but not saturated. After rooting (typically in 10 to 14 days) gradually reduce irrigation frequency to once or twice per day while maintaining a moist root zone.
4. Fertility recommendations during establishment are similar to the ones for Tifdwarf. Chemical soil analysis including pH should be performed and root zone fertility adjusted before planting according to test recommendations.
A. Preplant suggestions
N 0.5lb/1000 sq ft
P 2 lb/1000 sq ft or 2.5-3 lbs/cu. yd. root zone mix
K 2 lb/ 1000 sq ft. minor elements
B. Grow-in suggestions, maximum rates
N 0.5 lb/1000 2 times per week during active growth.
P & K Alternate NH4N03 /(NH4 )2SO4 with complete analysis materials such as 5-20-20 on weekly basis. Maintain N:K ratio at least 1: 1, increase to 1:2 prior to cool weather.
5. Mowing: Do not allow TifEagle to grow several weeks without mowing.
A. Begin mowing at approximately 0.375 " shortly after shoot growth is initiated. Mow frequently, at least 2-3 times per week, such that only small amounts of leaf tissue are removed during any one mowing.
B. At least 80% coverage should be obtained in 30 days. Mowing height should be lowered to 0.250" within this period.
C. Coverage should be 100% within 60 days. During this period mowing height should be lowered to 0.125".
6. Reducing surface irregularities:
A. Topdress after 80% coverage
a. 1-2 heavy applications to fill depressions. Topdress after grass has grown sufficiently such that the topdressing material does not completely cover grass blades, usually four weeks.
b. Begin regular topdressing at 100% coverage, Regular light topdressing applications should be continued on a weekly or biweekly schedule.
c. Use consistent, good quality top-dressing sand.
B. Roll the surface as needed.
7. Increasing turf density:
A. Daily mowing
B. Frequent spiking or slicing
8. Weed Control is similar to Tifdwarf. Remove broadleaf and grassy weeds by hand. Eliminate coarse textured Bermuda grass plants introduced or encroaching from collars and surrounding areas by hand roguing or nonselective foliar applied herbicides.
9. Other planting procedures.If TifEagle is planted as sod from plastic, sand based fields or washed sod, greens should be aerified with core removal after sod is rooted to minimize root zone layering.
III. Routine management during active vegetative growth.
1. Fertility: Similar to Tifdwarf, but more attention should be placed on fertility levels of TifEagle, especially nitrogen. Apply only enough nitrogen to maintain a quality putting surface.
A. Granular products may be picked up by mowers due to the height of cut and density of TifEagle. Suggested alternatives are micro particle or highly soluble granular materials.
B. Use of liquid fertilizer materials has improved consistency of TifEagle color and putting surface performance.This is probably due to the ability to better manage plant tissue nutrient levels.
C. High rates of N will intensify thatch buildup.
D. Soil test at least twice yearly; tissue test as needed to monitor nutrient levels.
2. Water requirements are similar to Tifdwarf.Irrigate to prevent stress.
3. Mowing height:
A. Mow at least once daily at 0.125" or lower during periods of active growth. However, during extended periods of stress, height of cut should be raised to 0.156".
B. Walk behind mowers are preferred over triplex mowers.
TifEagle has been shown to tolerate mowing 2-3 times per day at a height of 0.112". Stimpmeter measured putting speed was 8.5 at the beginning and near 10 ft. at the end of the test period. TifEagle has tolerated daily double mowing at 0.10" without loss of stand density.
4. Thatch prevention: Akey concept is THATCH PREVENTION rather than thatch control. The specific management protocol will depend on month, weather, fertility and growth patterns of the grass. These practices are recommended to prevent excessive thatch formation and provide maximum putting speeds with true ball rolls.
A. Frequent light topdressing (0.125-0.250 cu. yds/1000 sq. ft., fine to medium sand) at least once every 2 weeks.
B. Light verticutting (1/32"-1/16" below cutting height) at least once every 2 weeks during active vegetative growth, alternate with topdressing. Once per month has not been satisfactory.
C. Aerify 3 - 5 times minimum per year using 2" tines on 2" centers. Remove aerification cores and debris. Sufficient topdressing material should be applied and worked in to backfill aerification holes.
D. Severely verticut once per year.
E. Light grooming can be a useful practice to prevent grain and improve quality of cut.
5. Pest management requirements are similar to Tifdwarf.
IV. Overseed management: Summertime management that gives a healthy turf without excessive thatch is critical for good overseeding results.
A. Surface preparation: Lightly verticut to thin and open canopy. Number of verticut replications and depth will depend on the summertime management and the extent of the thatch layer.
B. Species: Smaller seeded species are preferred.
a. Poa trivialis alone or with 10-20% bentgrass. The use of a bentgrass variety with low heat tolerance is recommended.
b. Ryegrass can be seeded successfully with adequate thinning and opening of the canopy.
C. Seeding rate: total 10-20 lbs/1000 sq. ft.
E. Irrigate as needed to keep seed bed moist throughout the day during germination and seedling establishment.
F. Mowing: Raise height of cut to 0.188" until stand is established.
G. Disease control: Use fungicide treated seed. Preventative fungicide applications for 3-4 weeks is suggested for Pythium control
2. Spring transition: Practices that have led to successful spring transition with Tifdwarf should be successful when incorporated into the TifEagle management protocol.
A. When weather and course conditions are appropriate for transition, lower cutting height to 0.125" or less.
B. Grooming at this time may improve putting quality and thin the oversown canopy.
C. Begin routine aerification.
D. Increase fertility to encourage bermudagrass growth.