GCM

Velvet bentgrass: Rediscovering a misunderstood turfgrass

Past mistakes have damaged an excellent species's reputation.

Leah A. Brilman, Ph.D., and William A. Meyer, Ph.D.

Key Points

{short description of image}Widely considered the most attractive turfgrass, velvet bentgrass may possess many cultural advantages over creeping bentgrass.

{short description of image}Early breeding techniques produced unimpressive cultivars with weak seed production that may have limited the appeal of velvet bentgrass.

{short description of image}Researchers are developing new velvet bentgrass cultivars.

Better putting surfaces. Greater tolerance of wear, drought, heat, disease and shade. Lower fertility requirements. Compared with creeping bentgrass (Agrostis palustris), the characteristics of velvet bentgrass (Agrostis canina) seem to be superior. So why is velvet bentgrass not used on more golf courses in the United States? The answer is complex and related to the evolution of the golf course industry and maintenance practices in the United States and evolution of the turf seed industry.

Early studies
Velvet bentgrass has long been appreciated for forming a uniquely beautiful turf surface with its fine texture and high shoot density (3,13). In 1932, 10 professional golfers selected it as the best putting surface when invited to putt on greens at the Arlington (Va.) Turf Gardens, which featured the top vegetative creeping bents, colonial bents (Agrostis tenuis) and velvet bentgrasses (6). Researchers described the turf as "luxurious green velvet" (13).

The species purportedly demands intense maintenance, however, and it allegedly cannot grow anywhere but temperate-oceanic climates such as New England and the Pacific Northwest (2,14). At least one expert disagrees somewhat, noting the species's good tolerance of heat and low temperatures and its superior tolerance of drought compared with other bentgrass species (1).

Early trials (8,11) revealed that velvet bentgrass is more tolerant of acidic soils than other bentgrasses and that velvet bentgrass was the most shade-tolerant of the bentgrasses (12). Others observed that velvet bentgrass does not spread as rapidly as some other bents but is very persistent once established (13).

Velvet bentgrass was introduced to many U.S. turf sites from seed harvested in Europe and imported as South German bent, which usually consisted of about 75 percent Rhode Island bentgrass (now known as colonial bent), 15 percent velvet bentgrass, 1 percent creeping bent and many impurities (10).

Some evidence suggests, however, that velvet bentgrass may be a native North American species in portions of its distribution (5,15).

Velvet bentgrass (right) is not only finer than creeping bentgrass (left), but is also more tolerant of many stresses that weaken creeping bentgrass cultivars.
Velvet bentgrass

Whether from Europe or North America, over time the few adapted ecotypes segregated out and spread vegetatively. This process produced the early vegetative cultivars of creeping bentgrass, such as Arlington and Toronto, and certain superior genotypes of velvet bentgrass, which were selected by early golf course superintendents and turf researchers and increased vegetatively for planting on additional golf courses.

These early varieties included: Piper velvet bentgrass, selected by the USGA Green Section; Merion, a selection from the Merion Cricket Club, Ardmore, Pa.; and Kernwood, a selection from the Kernwood Country Club, Salem, Mass. (3).

Other early selections included Mountain Ridge, from the USDA; Highland velvet; Yorkshire, from Yorkshire, England; Newport velvet, from Washington Co., Ore.; Valentine No. 2 from Joseph Valentine at Merion CC; Acme, from the USGA Green Section and USDA; Wykagyl, from Wykagyl Country Club in New Rochelle, N.Y.; Nichol Ave. Nos. 1 and 2, from Rutgers University, N.J.; Cunningham, from the USGA Green Section; and Elizabeth, from Elizabeth, N.J. (8).

In the 1930s, Rhode Island farmers also produced some seed from Piper and Kernwood (9), which may have been an additional source of velvet bentgrasses still found on older golf courses. Unreliable seed supplies were the primary reason velvet bentgrass was not used more extensively (9,13). According to these early reports, velvet bentgrass seed produced in North America came primarily from naturalized stands in Oregon and Prince Edward Island, Canada (8). These sites may have included native ecotypes of velvet bentgrass, but the record is unclear.

In addition to evaluating vegetative velvet bentgrasses, the early researchers also produced self-pollinated seed and evaluated the progeny for uniformity and plant characteristics (3). In 1930, turf researcher H.B. Sprague planted all available varieties and developed the seeded variety Raritan released by the New Jersey Agricultural Experiment Station in 1940 (4). Unfortunately this variety was lost during World War II.

Later, the seeded variety Kingstown (Kingston) was released by C.R. Skogley and J.A. DeFrance from an inbred selection (4).

This early breeding work may have weakened the species's appeal for the next several decades. Seed production problems arose, perhaps from breeders' utilization of inbred material or because infertile progeny resulted from crosses with other bentgrass species. Kingstown was also lighter green than many other bentgrasses, which may have contributed to excessive fertilization. Heavy thatch development, disease outbreaks and Poa annua encroachment followed, which led to the misconception that velvets produce a high-maintenance turf.

Rediscovery
Skogley, of University of Rhode Island, never stopped working with velvet bentgrasses. With germplasm at the university and material from old golf courses, he sought improvements in velvet bentgrasses, emphasizing color, disease resistance and turf quality. In cooperation with Seed Research of Oregon, the variety SR 7200 (Avalon in Europe) was released. A difficult task lay ahead of having this variety properly evaluated and brought into use. Many golf courses had been moving to lower fertility, however, and newer varieties of creeping bentgrasses had led to the development of improved techniques for thatch control. The University of Rhode Island has continued to work on evaluation and breeding of velvet bentgrasses under Bridget Ruemmele, Ph.D.

Rutgers University has been instrumental in helping evaluate the strengths and weaknesses of velvet bentgrass outside of the traditional New England area. As part of their turfgrass breeding program they have a new experimental velvet bentgrass, developed from a velvet planted 20 years ago in an old turf trial. This velvet persisted and spread over many years of reduced inputs. In addition, turf researchers at Rutgers have been collecting germplasm of velvet bentgrasses from many old courses in New York, Connecticut and New Jersey. They have planted many experimental turf plots at both fairway and greens height and maintained them at lower fertility to help evaluate existing and experimental varieties for reduced maintenance. On many of their trials, they have also applied wear to look at this important characteristic. These trials have not only helped examine current varieties, but they also will help develop new varieties of all bentgrasses with reduced input requirements.

Velvet bentgrass stands out in this naturalized stand.
Velvet bentgrass

Velvet bentgrass characteristics
SR 7200 (Avalon) velvet bentgrass and new experimental varieties have demonstrated excellent resistance to many turfgrass diseases, including dollar spot (Sclerotinia homoeocarpa) and brown patch (Rhizoctonia solani). In early and recent trials, collected germplasm has shown variable reaction to these diseases.

Piper was fairly susceptible to brown patch, but most selections offered good resistance. Improvement in this species has emphasized selecting germplasm with excellent disease resistance.

Copper spot has traditionally been associated with velvet bentgrass, but SR 7200 has shown fewer incidences than many creeping bentgrasses. Pythium diseases have been observed to attack seedling velvet bentgrass more than creeping bentgrass, but mature velvet appears to be highly resistant to this disease.

Initial reports from the 1998 Bentgrass Greens NTEP Trial suggest Pythium problems may have reduced the stands of the velvets in this trial at some locations during the seedling stage before turf managers noticed. It has occasionally shown take-all patch (Gaumannomyces graminis avenae) in the initial year or two in the Pacific Northwest, but has shown good resistance to fusarium patch (Microdochium nivale). At Rutgers in the fall of 1999 the velvet bentgrasses suffered some damage by fusarium patch in an area with poor air circulation.

Velvet bentgrass in trials at both the Sports Turf Research Institute in Bingley, England, and at Rutgers University has shown improved wear tolerance compared with many creeping or colonial bentgrass varieties (7). The high shoot density of velvet bentgrass may contribute to this wear tolerance. These trials were both at lower fertility levels, and results may change if high fertility is used, which tends to favor creeping bentgrasses. In the England trial, SR 7200 was also the most drought-tolerant of the bentgrasses.

The fine texture and good quality of velvet bentgrass turf (center) stands out from other bentgrasses in these plots.
velvet betgrass

Potential use
The area of adaptation on velvet bentgrass for permanent turf is not as limited as some literature would suggest. The success at Rutgers University and at early trials at Arlington Turf Gardens suggests this species can be used successfully farther south than commonly perceived.

The primary area of adaption appears to be a zone across the United States from portions of Maryland and Virginia, southern Ohio, and across to Columbia, Mo., where we have maintained it successfully at fairway height.

In the western United States, it will do well in many areas, including Oregon, Washington and much of California. Elevation and microclimates will influence this area of adaptation. This is also where creeping bentgrasses were best adapted until breeding efforts moved the area of adaptation farther south. This area may change as breeders further improve the species, or we learn how to manage it better farther south.

Velvet may perform well farther south in shaded locations, because it is the most shade-tolerant bentgrass. It has been successfully used on shaded tees, where blending with chewings fescue (Festuca rubra commutata) is usually recommended for more rapid coverage in divot-repair mixes.

Overseeding
The area of adaptation of velvet bentgrass suggests another potential use: overseeding of bermudagrass (Cynodon hybrids) on golf courses in the southern United States for winter play. The perennial ryegrasses typically used for this often do not transition well. This has become a more serious problem on some of the new ultra-dense bermudagrasses such as TifEagle, Champion and Floradwarf. We have experimented with SR 7200 combined with Poa trivialis, chewings fescue and perennial ryegrass in overseeding mixtures. The velvet bentgrass cultivar provides excellent winter-to-spring grass and transitions rapidly when the heat comes on, and initial golf course reports have been favorable.

Reliable seed supply
One problem associated with earlier velvet bentgrasses was obtaining high-quality, reliable seed supplies of improved varieties. Newer varieties are developed with attention to seed production, utilizing multiple clones so problems with inbreeding do not occur. Care must also be taken to ensure that outcrossing with other bentgrass species does not occur. SR 7200 has been in commercial seed production for five years with yields comparable to that of improved creeping bentgrasses. Other varieties are just being entered into commercial production.

Conclusions
Velvet bentgrasses form a superior turf surface with reduced inputs of fertilizer and fungicides. Further evaluation and breeding work in this species are desirable to define the optimal range and management of the species. It is time for current turf managers to rediscover the assets of velvet bentgrasses that made early researchers consider this the grass of the future.

Literature cited

  1. Beard, J.B, 1973. Turfgrass: Science and culture. Prentice-Hall, Englewood Cliffs, N.J.
  2. Christians, N. 1998. Fundamentals of turfgrass management. Ann Arbor Press, Chelsea, Mich.
  3. DeFrance, J.A., T.E. Odland and R.S. Bell.1952. Improvement of velvet bentgrass by selection. Agronomy Journal 44:376-378.
  4. Hanson, A.A. 1972. Grass varieties of the United States. Agricultural Handbook No. 170. USDA, Agricultural Research Service, Beltsville, Md.
  5. Hitchcock, A.S. 1950. Manual of the grasses of the United States. U.S. Government Printing Office, Washington, D.C.
  6. Monteith, J., Jr., and K. Welton. 1932. Putting tests upon bentgrasses. Bulletin of the USGA Green Section 12(6):224-227.
  7. Newell, A.J., F.M.E. Crossley, J.C. Hart-Woods, C.E. Richards and A.D. Wood. 1997. STRI report to turfgrass breeders 1997. Sports Turf Research Institute, Bingley, West Yorkshire, U.K.
  8. North, H.F.A., and T.E. Odland. 1934. Putting green grasses and their management. Rhode Island Agricultural Experiment Station Bulletin 245:1-44.
  9. North, H.F.A., T.E. Odland and J.E. DeFrance. 1938. Lawn grasses and their management. Rhode Island Agricultural Experiment Station Bulletin 245:1-36.
  10. Piper, C.V. 1918. The agricultural species of bent grass. Part I. Rhode Island bent and related grasses. USDA Bulletin 692:1-14.
  11. Reid, M.E. 1932. The effects of soil reaction upon the growth of several types of bentgrasses. Bulletin of the USGA Green Section 12(5):196-212.
  12. Reid, M.E. 1933. Effects of shade on the growth of velvet bent and Metropolitan creeping bent. Bulletin of the USGA Green Section 13:131-135.
  13. Sprague, H.B., and E.E. Evaul. 1930. Experiments with turf grasses in New Jersey. New Jersey Agricultural Experiment Station Bulletin 497.
  14. Turgeon, A.J. 1996. Turfgrass management. 4th ed. Prentice Hall, Upper Saddle River, N.J.
  15. U.S. Department of Agriculture. 1999. The PLANTS database. Available at http://plants.usda.gov/. National Plant Data Center, Baton Rouge, La.

Leah Brilman, Ph.D., is a breeder with Seed Research of Oregon. William A. Meyer, Ph.D., is associate director of the Rutgers University Center for Turfgrass Science and a professor of plant science.