Bermudagrasses: An Update

By Tom Samples and John Sorochan, University of Tennessee, Department of Plant Sciences

Bermudagrass, an aggressive sod-forming and warm-season turfgrass, most likely originated in Africa and south and southeastern Asia. It is believed that the species was introduced into the U.S. in the mid- 1700’s from seed in hay used as bedding on ships sailing from Africa to America. Some turf-type bermudagrasses in today’s marketplace are non-seed bearing hybrids of two Cynodon species, C. dactylon (Common) and C. transvaalensis (African), and must be vegetatively established. Others are improved varieties of ‘Common’ bermudagrass and are prolific seed producers often referred to as ‘seeded-types’. Plants spread by both above- and belowground stems referred to as stolons and rhizomes, respectively.

Bermudagrass grows best in open areas receiving full sun and although a limited number of varieties have improved shade tolerance, the species is generally not well adapted in moderately to heavily shaded areas. Leaves and stems become strawbrown as plants enter dormancy each fall. A healthy, actively growing bermudagrass turf is dense, uniform, resistant to weed invasion and capable of quickly recovering from wear injury. Under ideal growing conditions, and in nutrient-rich soils, newly planted sprigs of several varieties may grow at the rate of ¾-inch or more per day.

The species tolerates sandy to clayey soils, however both hybrid and common bermudagrasses grow poorly in infertile soils that remain wet for an extended period. Depending on management intensity level, the nitrogen (N) fertility requirement of bermudagrass usually ranges from ½ to 1½ lbs. of N per 1,000 sq. ft. per growing month. Bermudagrass turfs are often routinely dethatched and are susceptible to several patch diseases including pink snow mold (Microdochium nivale), large patch (Rhizoctonia solani) and spring dead spot (Ophiosphaerella spp.). Common insect pests include armyworm (Pseudaletia unipuncta), fall armyworm (Spodoptera frugiperda) and white grubs (larvae of several species of Scarab. beetles). Winter annual weeds such as annual bluegrass (Poa annua), common chickweed (Stellaria media), henbit (Lamium amplexicaule) and purple dead-nettle (Lamium pupureum) may appear in bermudagrass turfs during winter dormancy. Several perennial weeds with energy-rich, below-ground bulbs or tubers such as yellow nutsedge (Cyperus esculentus), green (Kyllinga brevifolia) and false-green (Kyllinga gracillima) kyllinga, wild garlic (Allium vineale) and wild violet (Viola spp.) can become problematic as they compete with bermudagrass plants for water, nutrients, light and space.

Identification.

Both the upper and underside of leaves of bermudagrass may be smooth or hairy. The midvein appears as a slight fold in the center of the leaf and runs parallel to the edges. The leaf tip is sharply pointed and the ligule is a fringe of hairs. The collar is continuous and hairs are visible on the collar region at the junction of the leaf blade and sheath. Plants have no auricles (small outgrowths from the base of the leaf blade at the collar). The seedhead has from three to six or more spikes atop a flowering stem and resembles a bird’s foot.

Auricles – Absent

Leaf Tip – Sharply pointed

Collar – Continuous

Leaf Blade – Flat with visible midvein

Ligule – Short membrane with hairs

Sheath – Compressed to round, loose, split,

Vegetative/Clonal Types.

The first recorded release of an improved, turf-type bermudagrass variety occurred in 1947 with the release of ‘U-3’ by the United States Golf Association (USGA) in cooperation with the United States Department of Agriculture (USDA). This variety was found growing in Savannah, GA in 1938. In 1956, the soft, low-growing sterile hybrid variety ‘Tifgreen’ was jointly released by the Georgia Agriculture Experiment Station (AES) and the USDA- Agricultural Research Service Crops Research Division (ARS/CRD). ‘Tifway’, another sterile hybrid variety selected and cooperatively tested by the USDA, the Georgia Coastal Plain Experiment Station (ES), and the U.S. and Southern Golf Associations was released for production to sod growers in 1960. The USDA and the University of Georgia Coastal Plain Experiment Station jointly released ‘Tifdwarf’, a dwarf mutant of Tifgreen, in 1965. It has a darker green color and shorter leaves, stems and internodes than Tifgreen. Tifdwarf also establishes slower than Tifgreen when sprigged at the same planting rate. For many years, these three varieties with the prefix ‘Tif’, two recommended for use on golf greens and intensely managed lawns, the other for golf course fairways, sports fields and lawns, have served as standards to which new bermudagrasses are compared.

Vegetatively established varieties marketed throughout Tennessee vary in overall quality, and in traits including leaf texture, color, stand density, vertical and lateral growth rate, water use rate, low-temperature hardiness, and disease and insect resistance (Tables 1 and 2).

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Table 1:

Year of Introduction of Several Vegetative/Clonal Bermudagrasses, the Agency, Institution or Company, the Accession, Registration and/or Patent Numbers, and Variety Development Information.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Astro Not a Protected Variety

Year of Introduction or Patent, Agency, Institution or Company:

2017, Oklahoma State University

Comments: Chance find in Tifway bermudagrass in Astrodome in Houston, TX in the late 1960s.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Celebration (Known in Australia as Riley’s Super Sport) PP011181

Year of Introduction or Patent, Agency, Institution or Company:

2000, Sod Solutions, Inc.

Comments: Mutant of the unpatented Cynodon dactylon variety ‘Greenlees Park’ selected by the late Rod Riley, Guilford, New South Wales in 1988 and vegetatively propagated through four generations.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

GN-1 US6841P (CT-2 in Australia, AU1601988 A)

Year of Introduction or Patent, Agency, Institution or Company:

1989, H&T Whiting Turfgrass Development

Comments: Released after seven years of breeding in CA and three generations of crosses of 6 bermudagrasses from Africa, Australia and the U. S.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Latitude 36 (OKC1119) PP24271

Year of Introduction or Patent, Agency, Institution or Company:

2012, Oklahoma Agricultural Experiment Station, Oklahoma State University

Comments: C. dactylon (accession A 12198) × C. transvaalensis (OSU selection ‘2747’ from OK State internal holdings).

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Midlawn PP08162P

Year of Introduction or Patent, Agency, Institution or Company:

1991, Kansas State Research Foundation/ Kansas (KSU) AES and Oklahoma AES

Comments: C. dactylon (collected from Michigan State Univ. campus) x C. transvaalensis (1 of several plants growing in a polycross nursery in Ft. Hayes, KS).

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Northbridge (OKC1134) PP24116

Year of Introduction or Patent, Agency, Institution or Company:

2012, Oklahoma Agricultural Experiment Station, Oklahoma State University

Comments: C. dactylon var. dactylon (accession 3200E 4-1) × C. transvaalensis (OSU selection ‘2747’).

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Patriot (OKC18-4) PP16801P2

Year of Introduction or Patent, Agency, Institution or Company:

2002, Oklahoma Agricultural Experiment Station, Oklahoma State University

Comments: Cross of Cynodon dactylon (‘Tifton 10’) by C. transvaalensis (field nursery identity 4200 TN 26-8).

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Quickstand

Year of Introduction or Patent, Agency, Institution or Company:

1992, USDA-Natural Resources and Conservation Service (NRCS), USDA-ARS and University of Kentucky AES

Comments: Increased from a single C. dactylon accession found at the Quicksand, Kentucky Plant Materials Center.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Tahoma 31 (OKC1131) Plant Patent applied for, patent pending

Year of Introduction or Patent, Agency, Institution or Company:

2018, Oklahoma Agricultural Experiment Station, Oklahoma State University

Comments: Information not released at this time

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Tifdwarf (Reg. No. 8)

Year of Introduction or Patent, Agency, Institution or Company:

1965, Georgia Coastal Plain ES and Plant Science Research Division, ARS

Comments: Believed to be a natural occurring dwarf mutant of Tifgreen. Found growing on Tifgreen golf greens at Country Clubs in Florence, SC, and Sea Isle and Thomasville, GA.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

TifGrand (97-4, 00-07, Tift No. 4, ST-5) PP21017

Year of Introduction or Patent, Agency, Institution or Company:

2010, University of Georgia College of Agricultural and Environmental Sciences and USDA- ARS

Comments: C. transvaalensis x C. dactylon. Selected from a field population produced in Tifton, GA in 1992 by crossing six C. transvaalensis breeding lines (T572, T573, T574, T575, T576 & T577) selected for persistence under low management w/ four C. dactylon parents: T90 and T110 (selected for persistence under close mowing), and Quickstand and Vamont (selected for cold tolerance).

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Tifgreen (Tifton 328)

Year of Introduction or Patent, Agency, Institution or Company:

1956, Georgia AES and USDA- ARS/CRD

Comments: C. dactylon (selection from Green #4, Charlotte C. C., Charlotte, NC) x C. transvaalensis.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Tifton 10

Year of Introduction or Patent, Agency, Institution or Company:

1988, USDA-ARS and Georgia Coastal Plain AES

Comments: C. dactylon (collected in 1974 from a lawn in Shanghai, China).

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Tifsport/ Tift 94 (MI40) PP10079

Year of Introduction or Patent, Agency, Institution or Company:

1995, USDA-ARS & University of Georgia Coastal Plain ES

Comments: One of 66 single plant mutant selections resulting from the irradiation of dormant stolons of ‘Midiron’ (Cynodon dactylon x C. transvaalensis) bermudagrass.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

TifTuf (DT-1) PP027392

Year of Introduction or Patent, Agency, Institution or Company:

2016, USDA-ARS & University of Georgia Coastal Plain ES

Comments: C. transvaalensis x C. dactylon hybrid systematically evaluated since 2002 in three drought trials and two normal input trials in Tifton, GA. Additionally tested in FL, GA, OK and TX and in drought stress, irrigated/non-stress and traffic-stress trials.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Tifway (Tifton 419)

Year of Introduction or Patent, Agency, Institution or Company:

1960, USDA, GA Coastal Plain Expt. Sta. and U. S. and South. Golf Associations

Comments: Chance hybrid between C. transvaalensis and C. dactylon found in a seed lot of African bermudagrasses from Johannesburg, South Africa in 1954.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Tifway II

Year of Introduction or Patent, Agency, Institution or Company:

1971, USDA ARS/ Southeast Area and GA Coastal Plain ES

Comments: Mutant resulting from irradiated, dormant sprigs of Tifway.

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Variety, Accession (AN), Registration (RN) & Patent Protection (PP) #s:

Vamont (VPI C-1)

Year of Introduction or Patent, Agency, Institution or Company:

1980, Virginia AES

Comments: Collected after being observed in 1972 growing on a golf course fairway near North Wilkesboro, VA.

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Table 2:

Characteristics of Several Vegetative/Clonal Bermudagrass Varieties.

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Astro: Excellent overall turf quality, dense, medium-textured, fast recovery, and good wear resistance. Improved winter hardiness compared to non-improved common bermudagrasses such as U-3. Similar in overall quality and leaf texture to ‘Celebration’ and Patriot. Lighter green color than several other vegetative-type bermudagrasses. Density similar to that of Patriot.

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Celebration: Dark blue-green color, low growing, adaptable in light to medium shade, improved drought tolerance, high node density with a medium stolon internode length of 13.6 mm, medium lateral extension rate and excellent durability. Mean leaf length of 8 mm, leaf width of 1.7 mm and leaf length to width ratio of 5/1. Minimal seedhead production. Good low-temperature tolerance and excellent frost tolerance. Adapted in USDA Plant Hardiness Zones 6b to 11.

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GN-1: Dark green color, medium-fine textured, good low-temperature hardiness, excellent wear tolerance, upright leaves and improved nematode resistance.

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Latitude 36: Triploid interspecific hybrid propagated vegetatively. Excellent overall turf quality, fine texture, improved cold hardiness, high sod density, and very good sod tensile strength, wear tolerance and recuperation rate. Narrower leaves and shorter internodes than Tifway. Level of freeze tolerance similar to ‘Midlawn’ and superior to Tifway. Color resembles that of Tifway and is lighter green than ‘Patriot’. Stem diameter equivalent to that of Tifway. May transition from winter dormancy quicker than several other varieties.

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Midlawn: Slow-growing, dark-green, improved cold tolerance (to -20 ºF) with good sod density and drought tolerance. Leaf blades are about 1½ – 2½ mm wide. Similar to Tifway in overall turf quality when maintained at a medium-high level of management intensity. Resistant to spring dead spot (Ophiosphaerella herpotricha).

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Northbridge: Excellent overall turf quality, fine texture, improved cold hardiness, early spring green-up, high sod density, and very high sod tensile strength; Similar leaf blade length and leaf blade width to Tifway with a larger internode diameter than Tifway. Color is lighter green than that of Patriot and similar to Tifway; Sod density is slightly higher or equal to Tifway. Salinity tolerance better than or equal to Tifway; Slightly better winter hardiness than Latitude 36.

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Patriot: High aerial shoot density, relatively short internodes and medium texture. Good cold hardiness and excellent aerial shoot survival during winter. Leaf texture finer than that of Tifton-10 and color nearly the same dark blue-green. Slender rhizomes and stolons < 1 mm in diameter. Less susceptible to spring dead spot than Tifway.

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Quickstand: Medium-green, coarse-textured with thinner leaves than Vamont. Good cold tolerance (as low as -22 ºF with snow cover) and wear resistance. Establishes rapidly from sprigs. High light requirement. Demonstrates a low incidence of spring dead spot.

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Tahoma 31: Excellent overall turf quality, fine texture, exceptional cold hardiness, early spring green-up and improved drought resistance through lower water use rate. Similar in overall quality to Tifway. Fine leaf texture superior to Tifway. Slightly lighter in color than Tifway and Patriot and darker than Latitude 36. More dense than Patriot. Exceptional cold hardiness, often experiencing less winter injury than Latitude 36, Tifway and Patriot. Very good spring green-up, often earlier than Latitude 36, Tifway and Patriot.

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Tifdwarf: Darker green dwarf-type, with smaller stems and leaves, and shorter internodes than Tifgreen. More tolerant of close mowing than Tifgreen. Plants often turn purple when exposed to near-freezing temperatures.

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Tifgreen: Fine-textured dwarf-type, dense, forest green in color, rapidly spreading and disease-resistant w/ soft leaves. Less tolerant of low temperatures than Tifway. May at times produce a few yellowish-green seed heads with no viable seeds.

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TifGrand: Dwarf, dark green and fine textured with improved shade tolerance. Greater stand density than Tifdwarf or Tifgreen. Overall quality as good as or better than Tifway and Tifsport. Good cold and drought tolerance. High level of traffic tolerance and recuperative ability. Accumulates very little morning dew. May produce more seed heads than several other vegetative, clonal bermudagrasses.

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Tifsport: Selected in part for its ability to withstand close mowing, narrow leaves, density, improved color, resistance to southern mole cricket and sod webworm, and both wear tolerance and recovery. Leaves are narrower and internodes are shorter than those of Tifway.

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Tifton 10: Coarse textured with bluish-green color. Establishes rapidly. Sheds pollen yet produces very few viable seeds. Transitions from winter dormancy relatively early in spring and has good cold hardiness. Improved ring nematode (Criconemella ornata) tolerance. Produces less thatch than several other varieties.

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TifTuf: Excellent drought, wear and traffic tolerance. Good cold hardiness and color retention. Leaf characteristics and stand density similar to Tifway with improved recuperative ability. Color similar to or lighter green than Tifway depending on soil fertility level. Produces more and smaller seed heads than Tifway.

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Tifway: Medium textured, dark-green, dense and disease resistant with good wear tolerance and recovery. Leaves upright and not nearly as soft as those of Tifgreen. More resistant to sod webworm than Tifgreen. Good frost resistance and fall color retention.

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Tifway II: Has many of the same desirable characteristics of Tifway with greater frost tolerance and nematode resistance. Texture slightly coarser than and may transition from winter dormancy slightly before Tifway.

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Vamont: Medium green color, stand density and leaf texture. Produces very few, if any seed heads. Coarse, rapidly growing stolons. Good low-temperature hardiness, and traffic and wear tolerance.

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Vegetative, Ultra-dwarf Clonal Types.

Ultra-dwarf varieties such as ‘Champion,’ ‘Mini-Verde’ and ‘TifEagle’ have replaced both Tifgreen and Tifdwarf as varieties of choice for newly constructed or renovated greens in Tennessee (Table 3). They generally have shorter internodes, higher shoot densities, better overall turf quality and the ability to withstand lower cutting heights. Along with the improved overall putting surface of the ultra-dwarf bermudagrasses comes the need for a change in ‘conventional’ bermudagrass greens management practices. Research demonstrates that the ultra-dwarf bermudagrasses may be shallowly rooted and quickly produce excess thatch. Due to their very high aerial shoot densities, they may also prove challenging to topdress with sand meeting USGA specifications for putting green construction. Routine vertical mowing and applications of an appropriate wetting agent and plant growth regulator may be required. At times, two layers of winter protective blankets may be necessary to prevent severe low-temperature injury and desiccation in winter.

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Table 3:

Experimental Designation, Patent Number, Release or Patent Date of Several Ultra-Dwarf Bermudagrass Varieties and Their Characteristics.

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Variety (Experimental Designation) Patent Number, Date:

Champion PP09888, May 1997

Agency, Institution or Company:

Coastal Turf, Inc.

Characteristics:

A vegetative selection from Tifdwarf collected in TX. Very dense. Narrow leaf width. High rate of development of lateral stems. Thatch accumulation comparable to TifEagle. Relatively low N fertility requirement. Often produces a greater root mass than TifEagle.

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Variety (Experimental Designation) Patent Number, Date:

MiniVerde (P18) PP12084, September 2001

Agency, Institution or Company:

Modern Turf, Inc.

Characteristics:

A vegetative selection from what is believed to be a mutant of Tifdwarf. Primarily selected based on improved stand density, very fine leaves, uniform green color and rapid lateral growth rate. Shorter root structure than Tifdwarf.

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Variety (Experimental Designation) Patent Number, Date:

MS Supreme (MSB40) PP11781, February 2001

Agency, Institution or Company:

Mississippi Agricultural and Forestry ES

Characteristics:

Discovered growing in a Tifgreen (C. dactylon x C. transvaalensis) green on the Gulf Shores Country Club, Gulf Shores, AL. Forest green in color during summer with a short leaf blade (4 – 8 mm) and very fine width (0.4 – 1 mm), excellent aerial shoot density and a highly prostrate growth habit. Maintains uniform color under cloudy conditions and in the fall. Identified as Cynodon x magennisii.

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Variety (Experimental Designation) Patent Number, Date:

Sunday (referred to as C-1 after initial selection)

Agency, Institution or Company:

Sod Solutions, Inc.

Characteristics:

Selected in 2007 from a green on Cotton Creek Golf Club, Golf Shores, AL originally established from sprigs in 1987. Selection criteria included genetic stability, canopy density, lighter green color and limited seedhead production. Contributors to the selection include R. C. Craft, Robert Craft, John Chapman and Burr Johnson. John Chapman, primary developer.

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Variety (Experimental Designation) Patent Number, Date:

TifEagle PP11163, December 1999

Agency, Institution or Company:

USDA and Georgia AES

Characteristics:

A vegetative selection from what is believed to be a mutant of Tifdwarf. Primarily selected based on improved stand density, very fine leaves, uniform green color and rapid lateral growth rate. Shorter root structure than Tifdwarf.

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Latitude 36 (Left), Tifway (Right)

Northbridge (Left), TifTuf (Right)

TifTuf

Tifway

Seeded Types.

Historically, much of the bermudagrass seed marketed in Tennessee is harvested and processed in Arizona and New Mexico where two harvests may be possible annually. Common, also referred to as ‘Arizona Common’ bermudagrass, continues to be planted to establish lawns, sports fields, utility turfs and erosionresistant groundcovers throughout the south. However, Common bermudagrass is generally lighter in color, less dense, coarse textured, has a limited root mass and is more prone to low temperature and frost injury than many improved common types and vegetatively established hybrids. As a result, seed sales of the newer, improved turf-type common bermudagrasses continues to rise.

The varieties ‘Yukon’ and ‘Riviera’ released by Oklahoma State University in 2000 and 2001, respectively, have better quality, low-temperature tolerance, rooting and spring dead spot resistance than ‘Arizona Common’. Other improved common bermudagrasses marketed in Tennessee at this time include ‘Gold Glove’, ‘Mirage 2,’ ‘Monaco’, ‘North Shore SLT’, ‘NuMex-Sahara’, ‘Pyramid 2’ and ‘Royal Bengal’. Two or more varieties may be blended and sold in an effort to take advantage of the improved traits of each and provide buyers varieties that will establish and persist in several different microenvironments.

Turfgrass breeders continue to develop and evaluate new bermudagrasses. The National Turfgrass Evaluation Program (NTEP) “is designed to develop and coordinate uniform evaluation trials of turfgrass varieties and promising selections in the United States and Canada. Test results can be used by national companies and plant breeders to determine the broad picture of the adaptation of a cultivar. Results can also be used to determine if a cultivar is well adapted to a local area or level of turf maintenance”.

In addition to the sterile, vegetatively established bermudagrasses, green industry professionals may recognize many of the seeded types entered in the six NTEP National Bermudagrass Tests. Twenty-one vegetatively established and seven seeded varieties including ‘NuMex-Sahara’ and ‘Sonesta’ were entered in the first National Bermudagrass Test (NBT) in 1986. There were 10 vegetatively established and 16 seeded entries including ‘Cheyenne’, ‘Jackpot’, ‘Mirage’, ‘Primavera’ and ‘Sundevil’ in the 1992 NBT. Of the entries in the 1997 NBT, 18 were seeded types including ‘Blackjack’, ‘Blue-Muda’, ‘Majestic’, ‘Princess’, ‘Pyramid’, ‘Riviera’, ‘Savannah’, ‘Shangri La’, ‘Southern Star’, ‘Sundevil II’, ‘Sydney’ and ‘Transcontinental’, and 10 were vegetatively established. Twenty-nine of the 42 entries in the 2002 NBT were seeded types including ‘Contessa’, ‘LaPaloma’, ‘Mohawk’, ‘Panama’, ‘Southern Star’, ‘Sovereign’, ‘Sunbird’ and ‘Yukon’. Twenty-six of the 31 entries in the 2007 NBT were seeded types including ‘Gold Glove’, ‘Hollywood’, ‘Princess 77’, ‘Pyramid 2’, ‘Royal Bengal’, ‘Sunsport’ and ‘Veracruz’. The most recent NBT planted in 2013 contained 13 vegetatively established and 29 seeded types including ‘Monaco’ and ‘North Shore SLT’. A number of entries designated by letter and or number in this test will most likely be marketed as named varieties in the future. For more information regarding the disease and insect resistance, cold tolerance and overall performance of individual bermudagrass varieties, please visit the NTEP Website, http://www.ntep.org.

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