1997 Bermudagrass Trial in North Florida

A.E. Dudeck
University of Florida, Gainesville
Institute of Food and Agricultural Sciences

Bermudagrasses are widely used throughout southern United States for all types of turf cover on golf courses, sports turfs, and home lawns, as well as for erosion control on roadside rights-of-way, airfields, and levee embankments. Many different cultivars are being recommended, as well as many new cultivars are being developed by private industry and Agricultural Experiment Stations. The purpose of this study, which is part of a National Turfgrass Evaluation Program sponsored by the United States Department of Agriculture, is to evaluate performance of 34 bermudagrasses in North Florida. The basic study is being conducted at 18 locations in 15 states.

Materials and Methods

Thirty-four bermudagrass entries were established in field plots at our Turfgrass Field Laboratory, Gainesville, FL. Eighteen seeded entries were planted on 12 Aug. 1997 at a seeding rate of 0.85 pound per 1000 square feet. Preweighed seed was first placed in a shaker jar. It was then evenly dispensed by hand within a 4 by 6 foot seeder box, which provided uniform distribution of seed on each plot. Plots were then mulched with grass hay at a rate of 100 pounds of mulch per 1000 square feet. A continuous covering of a white shade cloth was stapled over the seeded and mulched plots to prevent erosion and movement of seed during germination and establishment. It was carefully removed at 10 days following seeding when green shoots were observed emerging through the shade cloth. Sixteen vegetative entries were plug-planted on 7 Aug. 1997. Twenty-four, 1.5 inch square plugs of each vegetative entry were planted on 1-foot centers. Plots were allowed to expand to a final size of 8 by 8 feet. An Arredondo fine sand (loamy, siliceous, hyperthermic Grossarenic Paleudult) had a soil reaction of 7.0 and was fumigated with methyl bromide prior to planting. Supplemental irrigation was applied twice daily during the first two weeks after planting and then only once daily thereafter to meet evapotranspiration needs throughout the remainder of the 1997 growing season. A fertilizer with a 21-8-11 analysis was applied at a rate of 1.0 pound of N per 1000 square feet at two and six weeks after planting. Plots were mowed at a one-inch height of cut with a mulching mower commencing 5 Sept. 1997. A reel mower without catchers set at 0.75 inch height of cut was used three times per week from 15 Sept. to close of the season.

A 15-0-30 fertilizer with water soluble N was applied in Apr., June, and Sept. of 1998 at a rate of one pound of N per 1000 square feet. Ammonium sulfate was applied on 23 July 1998 at a rate of one pound of N per 1000 square feet. Plots were mowed two to three times per week in 1998 at 0.75 inch with a reel mower. Clippings were not removed. Supplemental irrigation was applied daily throughout the study to meet evapotranspiration needs.

Visual estimates on bermudagrass ground cover from Sept. through Nov. 1997 were gathered weekly by up to three independent observers. Establishment rate was calculated after Maguire (1) and is presented in tabular form as a summation of ground cover estimates in percent over time divided by days from time of planting. Turf quality was visually rated at least twice a month on a scale of 1 to 9 where 9=best turf quality. Seed heads were visually rated in Apr. and June 1998 on a scale of 1 to 9 where 1=most seed heads and 9=no seed heads. Sod webworms were visually rated for damage to grass in July and Aug. 1998 on a scale of 1=susceptible and 9=resistance. Density and color was visually rated monthly throughout 1998 on a scale of 1 to 9 where 9=most density or darkest green color. Texture was rated in the summer, fall, and winter on a visual scale of 1 to 9 where 9=finest leaf texture. Greenup was visually rated on a scale of 1 to 9 where 9=earliest, greenest grass in spring of 1998. Thatch was subjectively rated at the close of the 1998 growing season by simply walking on plots to 'feel' sponginess or cushioning effects of each turf. Thatch was rated on a 1 to 9 scale where 1=most and 9=least thatch. All data were subjected to analysis of variance and means were separated where appropriate using Waller-Duncan k-ratio t-test at P=0.05 level. Experimental design was a randomized complete block with three replications.

Results and Discussion

Grasses that had highest rate of fall ground cover establishment, which averaged 20.0%, included 'Cardinal', 'FLoraTeX®', 'GN-1', 'Majestic', 'Midlawn', 'Mini-Verde', 'NuMex Sahara', 'OKC 18-4', 'OKC 19-9', 'Shanghai', 'Tifgreen', and 'TifSport' (Table 1). 'Majestic' and 'Mini-Verde' were seed established while the remainder of grasses were vegetatively established. This group of grasses attained 50% bermudagrass ground cover in 15.6±3.0 days.

Best grasses that had an average seasonal turf quality rating of 5.6 during the 1998 growing season included 'Cardinal', 'FLoraTeX®', 'GN-1', 'OKC 18-4', 'Princess, 'SW 1-11', 'Tifgreen', 'TifSport', and 'Tifway' (Table 2). Seasonal turf quality was lower than normal due to mechanical scalping with a problem mower in early fall and to serious sod webworm damage throughout fall and winter seasons. 'TifSport' had the lowest CV value of 14.5%, which means that its average turf quality score of 5.7 varied little over the 78 visual scores taken throughout the season.

Grasses that had best turf density scores, which averaged 6.5 during the first growing season, included 'J-540', 'FLoraTeX®', 'GN-1', 'Mini-Verde', 'OKC 18-4', 'Princess, 'TifSport', and 'Tifway' (Table 3). 'Mini-Verde' had finest leaf texture with an average score of 8.7 out of 9 where 9=finest leaf texture. Grasses that had darkest green genetic color scores, which averaged 7.2, included 'CN 2-9', 'FHB-285', 'TifSport', and 'Tifway'. Grasses that had darkest green winter color scores, which averaged 6.0, included 'Mini-Verde', 'OKC 18-4', and 'OKC 19-9'. Grasses that had earliest spring greenup scores, which averaged 5.6, included 'Cardinal', 'FLoraTeX®', 'GN-1', 'Mini-Verde', 'OKC 18-4', 'OKC 19-9', 'Princess, 'Tifgreen', 'TifSport', and 'Tifway'.

Seedheads are undesirable in turfgrasses because they detract from overall turf quality and may possibly produce viable seed, which would contaminate turf with other off-type grasses. Grasses that produced fewest seedheads during the first growing season included 'Cardinal', 'CN 2-9', 'FHB-44', 'FHB-201', 'FHB-281', 'FHB-285', 'Midlawn', 'TifSport', and 'Tifway' (Table 4). Their seedhead rating averaged 8.8 out of 9.0 where 9=no seedheads. Grasses that produced most seedheads, all of which were seed propagated, included 'Jackpot', 'Southern Star', 'Mirage', 'PST-R69C' 'Pyramid', 'Savannah' 'Sundevil II', and 'Sydney'. This group had an average seedhead rating of 2.8.

Sod webworms were a serious problem during the late summer, fall, and winter seasons of 1998. Many grasses (56%) showed resistance to this insect (Table 4). Interestingly, 79% of these grasses were seed propagated types. Grasses that had best resistance to sod webworms included 'AZ common', 'Blackjack', 'Blue-Muda', 'CN 2-9', 'FHB-285', 'FLoraTeX®', 'Jackpot', 'J-540', 'Majestic', 'Mirage', 'NuMex Sahara', 'PST-R69C' 'Pyramid', 'Savannah' 'Shangri La', 'Southern Star', 'Sundevil II', 'Sydney', and 'Tifway'. This group had an average webworm rating of 7.5 on a scale of 1 to 9 where 1=susceptible and 9=resistant. Grasses 'Mini-Verde' and 'OKC 19-9' were most susceptible to sod webworms. Both grasses had an average rating of 1.0.

Grasses that produced least thatch, when evaluated at the close of the 1998 growing season, included 'AZ common', 'Midlawn', 'NuMex Sahara', 'Shanghai', and 'Sydney' (Table 4). This group had an average thatch rating of 7.3 out of 9 where 9=least thatch. Grasses that produced most thatch, whose scores averaged 4.9, included 'CN 2-9', 'FHB-281', 'FHB-285', 'FLoraTeX®', 'OKS 95-1', 'TifSport', and 'Tifway'.

Results in this report are to be considered preliminary only as several additional years of study are required before sound conclusions may be drawn.

Literature Cited

1. Maquire, J.D. 1962. Speed of germination - aid in selection and evaluation for seedling emergence and vigor. Crop Sci. 2:176-177.

Table 1. Bermudagrass entries, method of propagation, cover rate, and days to 50% cover when planted at Gainesville, FL on 17 August 1997.
Entry Propagation Cover rate Cover50§
% d
OKC 19-9 P 22.4 a* 11.9±1.7
Tifgreen P 22.2 ab 12.3±1.7
FLoraTeX® P 21.0 a-c 13.8±2.0
OKC 18-4 P 20.8 a-d 14.2±1.3
NuMex Sahara S 20.6 a-e 15.5±4.1
Cardinal P 19.9 a-e 15.4±2.2
Shanghai P 19.7 a-e 15.7±1.2
Midlawn P 19.5 a-e 15.6±4.1
Mini-Verde P 19.4 a-e 15.7±5.2
TifSport P 18.1 a-f 18.7±3.2
GN-1 P 18.1 a-f 19.1±4.9
Majestic S 18.0 a-g 19.4±4.9
Shangri La S 17.7 b-g 19.2±5.4
Mirage S 17.5 b-g 19.4±5.6
AZ common S 17.0 c-h 20.8±4.1
Tifway P 16.3 d-i 23.4±2.3
Southern Star S 16.1 d-i 22.3±5.6
CN 2-9 P 16.1 d-i 23.8±2.4
FHB-44 P 16.0 e-i 24.5±5.0
Jackpot S 14.7 f-j 25.4±5.0
FHB-281 P 14.2 f-j 30.2±7.6
Savannah S 13.7 f-j 27.8±3.7
Pyramid S 13.5 f-j 28.5±4.4
Blue-Muda S 13.3 g-j 27.4±5.2
FHB-201 P 12.5 h-j 36.5±5.3
Blackjack S 12.3 i-k 29.1±3.1
FHB-285 P 11.7 i-k 39.5±5.7
Sundevil II S 11.6 i-k 32.9±5.1
OKS 95-1 S 11.3 j-l 34.9±6.3
SW 1-11 S 11.1 j-l 32.1±3.3
J-540 S 10.9 j-l 32.7±4.2
Sydney S 10.3 j-l 32.5±2.7
PST-R69C S 7.7 kl 39.9±1.7
Princess S 6.8 l 41.1±1.2

Planting method where P = plugs and S = seed.

Cover rate is a sum of averages based on visual percent ground cover divided by days after planting from Aug. to Nov. 1997.

§Cover50 values are days to 50% bermudagrass cover.

*Means followed by the same letter are not significantly different (P=0.05) using Waller-Duncan k-ratio t-test. A total of 21 observations were averaged.



Table 2. Seasonal estimates of bermudagrass turf quality during the first growing season in 1998 at Gainesville, FL.
Entry Spring Summer Fall Winter Season CV
Rating %
FLoraTeX® 6.3 6.1 5.7 5.6 5.96 a* 17.6
GN-1 6.3 5.4 6.0 5.3 5.79 a 18.4
TifSport 5.7 6.7 5.6 5.0 5.78 a 14.5
Tifway 5.6 6.5 5.6 5.0 5.69 ab 15.6
SW 1-11 5.3 6.3 7.1 4.2 5.63 a-c 23.6
Princess 6.4 5.5 5.5 4.2 5.46 a-d 23.9
Cardinal 6.1 4.6 5.0 5.9 5.46 a-d 20.4
OKC 18-4 5.8 5.8 5.1 4.9 5.44 a-d 19.1
Tifgreen 6.1 4.9 4.9 5.5 5.41 a-d 24.4
OKS 95-1 5.2 6.3 5.4 3.9 5.16 b-e 22.3
Mini-Verde 5.9 5.4 4.1 4.6 5.11 b-e 31.7
CN 2-9 4.9 6.0 4.6 4.4 5.02 c-f 17.9
FHB-285 4.9 6.5 4.7 3.9 4.99 d-f 27.0
Savannah 4.5 5.6 6.6 3.4 4.93 d-g 29.2
OKC 19-9 6.2 5.2 3.4 4.0 4.92 d-g 32.4
FHB-281 4.9 5.6 6.0 3.4 4.89 d-h 26.0
FHB-44 5.1 4.9 4.6 4.4 4.76 e-i 21.1
PST-R69C 4.6 5.8 5.2 3.4 4.72 e-i 25.4
J-540 4.4 56 5.8 3.4 4.72 e-i 24.9
Southern Star 4.7 5.7 5.1 3.3 4.67 e-i 27.7
Sydney 5.1 5.4 5.3 2.9 4.65 e-j 27.4
Mirage 4.5 5.3 5.8 2.5 4.46 f-k 33.2
Blackjack 4.1 5.3 5.5 2.8 4.36 g-k 34.1
Pyramid 4.1 5.5 5.5 2.5 4.30 h-l 35.7
Sundevil II 3.6 5.3 5.6 2.9 4.27 i-l 32.1
Majestic 3.9 5.6 5.3 2.3 4.20 i-l 38.9
Shangri La 3.6 5.4 5.4 2.7 4.19 i-l 37.5
Shanghai 4.3 5.1 4.4 2.8 4.16 i-l 24.3
Midlawn 4.4 5.0 4.0 2.6 4.03 j-l 30.6
Blue-Muda 3.3 5.3 5.4 2.4 4.01 kl 39.5
NuMex Sahara 3.0 5.2 5.8 2.6 3.99 k-m 43.1
Jackpot 3.7 4.8 5.0 2.3 3.87 k-m 35.6
FHB-201 3.9 4.8 3.3 2.7 3.71 lm 35.2
AZ common 2.5 4.8 4.9 1.8 3.39 m 51.3
MSD§ 1.3 0.5 1.1 0.9 0.62 -
CV = Coefficient of variation is a measure of relative variation around the seasonal mean expressed in percent. Both calculations were based on 78 observations throughout the season.

Quality visually rated on a scale of 1 to 9 where 9=best turf quality.

§MSD = Minimum significant difference between two means within a column which if exceeded is significantly different (P=0.05) using Waller-Duncan k-ratio t-test.

*Means followed by the same letter are not significantly different (P=0.05) using Waller-Duncan k-ratio t-test.



Table 3. Seasonal estimates of bermudagrass density, texture, genetic and winter color, and spring greenup during the first growing season of 1998 at Gainesville, FL.
Color
Entry Density Texture Genetic Winter Greenup
Rating
TifSport 6.97 a* 5.2 d 7.3 a 5.2 d-g 5.4 a-d
Tifway 6.64 ab 5.3 cd 7.0 a 4.6 h-k 5.3 a-e
Princess 6.54 a-c 2.7 g-j 5.8 cd 5.0 e-i 5.2 a-e
FLoraTeX® 6.49 a-d 3.0 e-h 5.2 e-f 4.3 jl 6.3 a
OKC 18-4 6.46 a-e 3.4 e-g 6.2 bc 5.8 a-c 5.4 a-d
Mini-Verde 6.44 a-e 8.7 a 6.1 bc 6.3 a 5.6 a-c
GN-1 6.38 a-f 3.0 e-h 6.0 bc 5.3 c-f 5.9 a-c
FHB-281 6.33 a-g 1.6 l 6.4 b 4.3 j-l 3.7 f-i
OKS 95-1 6.26 b-h 3.6 ef 5.4 de 4.5 h-l 4.5 d-g
FHB-44 6.26 b-h 7.4 b 4.3 h-j 4.7 g-k 5.0 b-e
SW 1-11 6.23 b-h 3.7 e 5.2 ef 4.4 i-l 4.4 d-g
CN 2-9 6.13 b-i 5.2 d 7.3 a 5.2 d-g 4.7 c-f
FHB-285 6.10 b-i 6.1 c 7.2 a 5.0 e-i 4.2 e-h
OKC 19-9 5.92 c-j 5.4 cd 63 b 5.9 ab 5.4 a-d
PST-R69C 5.85 d-k 2.4 h-k 4.9 fg 5.1 e-h 3.5 g-j
Southern Star 5.82 e-k 2.0 i-l 4.3 h-j 4.3 j-l 3.7 f-i
Cardinal 5.77 f-k 7.2 b 3.6 k 3.1 n 5.9 ab
Tifgreen 5.72 g-l 6.1 c 6.0 bc 5.5 b-e 5.8 a-c
Savannah 5.67 h-m 1.9 j-l 5.0 e-g 4.8 f-j 3.5 g-j
Majestic 5.64 h-m 2.6 h-j 4.3 h-j 4.4 i-l 2.5 j-l
J-540 5.52 i-n 2.7 g-j 4.5 g-j 4.5 h-l 3.6 f-i
FHB-201 5.41 j-o 7.1 b 5.3 ef 5.7 b-d 2.9 i-k
Pyramid 5.38 j-o 2.2 h-l 4.5 g-i 4.3 j-l 2.7 i-k
Sundevil II 5.38 j-o 2.8 f-i 4.1 h-j 4.3 j-l 2.8 i-k
Blue-Muda 5.36 j-o 2.9 e-h 4.3 h-j 4.0 lm 2.2 kl
Blackjack 5.33 j-o 1.7 kl 4.1 h-j 4.3 j-l 2.9 i-k
Shangri La 5.26 k-o 2.3 h-l 4.3 h-j 4.2 kl 2.6 i-l
Mirage 5.21 k-o 2.6 h-j 4.1 h-j 4.3 j-l 3.1 h-k
Sydney 5.10 l-o 2.4 h-k 3.9 jk 4.3 j-l 3.7 f-i
Midlawn 5.03 m-o 3.6 ef 5.0 e-g 3.6 mn 3.5 g-j
Jackpot 5.03 m-o 2.6 h-j 4.0 i-k 4.2 kl 2.7 i-k
Shanghai 4.87 n-p 1.6 l 5.8 cd 5.1 e-h 3.4 g-j
NuMex Sahara 4.77 op 2.6 h-j 4.6 gh 4.3 j-l 2.2 kl
AZ common 4.28 p 2.9 e-h 4.0 i-k 4.3 j-l 1.5 l
Ratings based on visual scale of 1 to 9 where 9=most dense, finest leaf texture, darkest green genetic and winter color, and earliest spring greenup. A total of 39, 9, 21, 30, and 24 observations were averaged, respectively.

*Means within columns followed by the same letter are not significantly different (P=0.05) using Waller-Duncan k-ratio t-test.



Table 4. Seasonal estimates of bermudagrass seedhead production, thatching tendency, and resistance to sod webworms during the first growing season of 1998 at Gainesville, FL
Entry Seedheads Webworms Thatch
Rating
FHB-44 9.0 a 1.1 lm 6.1 c-i
FHB-201 9.0 a 3.4 jk 6.1 c-i
Cardinal 9.0 a 4.6 h-j 6.1 c-i
FHB-285 9.0 a 8.2 a 5.0 j-m
Mini-Verde 8.9 a 1.0 m 6.3 b-h
CN 2-9 8.9 a 7.7 a-c 4.9 k-m
Midlawn 8.8 a 6.5 c-f 7.1 a-c
TifSport 8.7 ab 6.6 b-f 4.3 m
FHB-281 8.7 ab 6.0 e-g 5.1 i-m
Tifway 8.5 ab 7.2 a-e 4.6 lm
Tifgreen 8.1 bc 2.2 kl 6.0 b-f
OKC 18-4 7.7 cd 5.7 f-h 5.8 e-k
Shanghai 7.7 cd 6.4 d-f 7.3 ab
GN-1 7.5 d 3.9 ij 5.7 e-k
OKC 19-9 7.1 d 1.0 m 6.7 b-e
OKS 95-1 5.1 e 6.4 d-f 5.3 h-m
FLoraTeX® 4.7 e 7.3 a-d 4.9 k-m
Majestic 4.7 e 7.5 a-d 6.2 c-h
AZ common 4.5 ef 7.5 a-d 7.9 a
J-540 3.9 fg 7.8 ab 5.8 e-k
Blue-Muda 3.8 g 7.4 a-d 6.7 b-e
SW 1-11 3.6 gh 6.7 b-f 5.6 f-l
Princess 3.5 g-i 5.0 g-i 5.4 g-l
Blackjack 3.5 g-i 7.1 a-e 6.5 b-f
NuMex Sahara 3.5 g-i 7.7 a-c 7.1 a-d
Shangri La 3.3 g-i 7.6 a-d 6.7 b-e
Jackpot 3.1 h-j 7.5 a-d 6.7 b-e
Sundevil II 2.9 ij 7.4 a-d 6.4 b-g
PST-R69C 2.9 ij 7.6 a-d 5.9 e-j
Southern Star 2.9 ij 7.2 a-e 6.0 d-i
Pyramid 2.9 ij 7.7 a-c 6.1 c-i
Sydney 2.7 j 7.6 a-d 7.1 a-c
Savannah 2.6 j 7.3 a-d 5.7 e-k
Mirage 2.5 j 7.5 a-d 6.4 b-g
Ratings based on visual scale of 1 to 9 where 9=no seedheads, least thatch, and resistance to sod webworms. A total of 15, 15, and 9 observations were averaged, respectively.

*Means within columns followed by the same letter are not significantly different (P=0.05) using Waller-Duncan k-ratio t-test.