In the southern region of the United States, and all other areas with environments that favor warm season grasses, bermudagrass is a popular selection used for home lawns, golf courses, and athletic fields. Bermudagrass is a fast growing, sod forming perennial which forms a dense, uniform surface with excellent wear tolerance, quick recovery rate and good surface grip. Currently, the primary choices for high quality bermudagrass are the vegetatively propagated cultivars such as ‘Tifway’ (Cynodon dactylon X C. transvaalensis). These do not produce viable seed, and are readily available in sod or sprig form.

In recent years, many new cultivars of seeded bermudagrass (C. dactylon) have become available to the public due to genetic research and plant breeding efforts (2). Common bermudagrass was introduced in Yuma, AZ around 1900, but did not become certified as ‘Arizona Common’ until 1963 (3). During the 1980’s advancements were made, with the release of improved cultivars such as ‘Guymon’ for cold tolerance, and ‘Numex Sahara’ for overall quality (5). Numex Sahara is considered the first improved seeded bermudagrass that was bred specifically for turfgrass use (1). Also during the late 1990’s great advancements were made with the introduction of ‘Riviera’ and ‘Princess’. These new cultivars have shown similar quality to the vegetative hybrids. From the improved performance and the promising results of these cultivars, the future is bright for better development of seeded bermudagrass. A major concern with seeded cultivars is their ability to survive the winter of the establishment year. Severe winterkill is a possibility in areas with harsh winters (4).

Reduced cost and ease of planting are some of the benefits of using seeded cultivars rather than the vegetatively propagated cultivars. One of the primary concerns about the seeded cultivars of bermudagrass is whether they offer the same high quality characteristics, rapid recovery and growth rate as the hybrids.

We studied some of the new seeded bermudagrass cultivars during the summers of 2001 and 2002 in Auburn, AL, and Crossville, AL. The objective of this research project is to examine whether the new seeded cultivars of bermudagrass have a suitable shoot density, color/quality, and rate of coverage for use in home lawns, golf courses, and other general turfgrass areas.

Two separate experiments were established in June and August 2001 at the Auburn University Turfgrass Research Unit in Auburn, AL. Each research area was fumigated with methyl bromide three weeks prior to seeding. Plots were seeded with six different cultivars of C. dactylon at a rate of 2 lbs/1000ft2 on June 6, 2001, and August 16, 2001. The six cultivars of seeded bermudagrass used were ‘Princess’ (Seeds West), ‘Numex Sahara’(Seeds West), ‘Blackjack’ (Desert Sun Marketing), ‘Sydney’(Seeds West), ‘Bermuda Triangle’(Seeds West), and ‘Sultan’(Seeds West). On June 6th, Tifway was established via sod and on the August 16th planting, Tifway was sprigged at 5-10 bushels/1000ft2. Immediately after seeding, the plots were covered with a cotton row cover cloth to help retain moisture and reduce washing of seed from the plots. Immediately after germination, the covers were removed and an initial fertilizer application of greens grade fertilizer (18-3-18 @ 1 lb/1000ft2) was applied. Subsequent N fertilizer applications (ammonium nitrate 34-0-0) were applied at a rate of 1 lb/1000ft2 per week until 100% grass coverage. After establishment, a rate of 1 lbN/1000ft2 per growing month was applied. When the grass reached a height of 2 inches, it was mowed with a rotary mower at 11/ 2 to 2 inches three times a week. Irrigation and pesticide application were as needed during establishment and maintenance.

This test was also repeated a second year in the summer of 2002 at the Sand Mountain Substation, in Crossville, AL. Nine seeded cultivars of bermudagrass were planted at Sand Mountain on May 22, 2002, and August 16, 2002. The same six seeded cultivars from above were planted once again, with the addition of three more: ‘Riviera’ (Johnston Seed), ‘Guymon’ (Johnston Seed), and ‘Yukon’ (Johnston Seed). The procedure above was followed during the establishment at Sand Mountain. The only change in the procedure was the preparation of the ground for planting. Instead of methyl bromide, two applications of glyphosate were applied to prepare a clean seed bed.

After germination at both sites and both planting dates, percent coverage was estimated using a visual observation until 100% coverage was achieved. Shoot density was recorded once a month from two months after planting until the grass entered winter dormancy. Shoot density was also recorded for the summer following the 2001 AU TGRU planting in 2002. Shoots in three 2 ¼ inch-diameter plugs removed from each plot were counted by hand. Starting after the plots reached 100% cover, color and quality ratings were taken by visual observation once a month. As fall approached, fall color retention was noted. Winter-kill and spring green-up were both evaluated in spring 2002. They will also be evaluated in the spring of 2003 for the 2002 plantings.

RESULTS
Auburn University Turfgrass Research Unit 2001 During June establishment in 2001 at the AU TGRU, all of the seeded cultivars emerged at the same time, and had complete coverage within six weeks of planting. In the second planting (August 16) that year, the seeded cultivars emerged quicker, with complete coverage within four weeks after planting. The sprigged Tifway took nine weeks to obtain complete coverage. Shoot density of each cultivar was evaluated three months after the June planting. Tifway and Princess had the highest shoot densities, Blackjack was slightly lower, and the rest of the cultivars were slightly less, but similar to each other. Quality was also rated during this time, and once again Tifway and Princess were superior, with Blackjack following, and then the rest of the cultivars. As fall approached color retention was noted, and no differences among all the cultivars was observed.

Auburn University Turfgrass Research Unit 2002 As the bermudagrass began to come out of winter dormancy, spring green-up was recorded with all of the seeded cultivars greening up at a similar rate. The vegetative cultivar Tifway was the exception to this and was completely green one month prior to the seeded cultivars. Also after the grass came out of dormancy winter-kill was evaluated. Winterkill is a major concern the initial winter after establishment for seeded cultivars of bermudagrass. The different plant dates showed that an early plant date is important when establishing bermudagrass by seed. Tifway and Princess planted the previous June showed no signs of winterkill, while Blackjack had the highest rate at twenty percent. All other cultivars showed minimal winterkill. Plots planted in August were more susceptible to winterkill. For the August planting date, Tifway was the only cultivar with no winterkill. Princess and Sydney showed the least amount of winterkill among the seeded cultivars with less than ten percent. All the other cultivars showed similar susceptibility to winterkill (25-38 %), with Blackjack having the most at thirty-eight percent winter-kill. As summer approached, shoot density was also measured again. Similar to the previous year, Tifway had the greatest shoot density in the project throughout the entire summer. Princess was next, and the highest among the seeded cultivars. The remaining cultivars had significantly lower shoot density (Graph 1). Color and quality were also recorded during the summer of 2002 with similar results to shoot density with Tifway being superior, followed closely by Princess, and then the rest of the seeded cultivars (Tables 1 & 2).

Sand Mountain 2002 Establishment at Sand Mountain took slightly longer due to heavy weed pressure. Similar results were observed as in the previous year at the AU TGRU. All of the seeded cultivars established within 8 weeks, and the cultivars that established quicker had less competition from the weeds. Most of the cultivars filled in at the same rate, but Guymon and Yukon seemed to germinate slower, and not establish as quickly, and therefore encountered heavy weed pressure. Also, since Tifway sprigs are slow to establish, they had the greatest amount of weed infestation.

Shoot density for Sand Mountain (Graph 2) was determined as at the AU TGRU. Once they were completely established, Princess, Tifway, and Riviera were all similar in shoot density. All the other seeded cultivars were similar in their shoot densities. Princess and Riviera showed superior quality (Table 3). Note that Tifway quality is lower than expected. From the beginning of July to the middle of August irrigation was under repair, and could not be applied. The Tifway was not fully mature when the irrigation problem happened, and this slowed growth drastically. It did obtain full coverage in September soon after the irrigation was fixed. This research will be completed in the following spring and summer. Spring green up and winterkill will be recorded also color and quality will be noted throughout the summer.

The new seeded cultivars of bermudagrass are approaching the quality of hybrid bermudagrasses. Our research shows that the newer seeded cultivars are gaining ground, but are still not quite up to the standard of Tifway. However, the reduced cost, ease of planting and quick establishment of the new seeded bermudagrasses will make them viable options for many turfgrass mangers.

In conclusion, our research shows that:
• Some seeded cultivars establish much quicker than sprigged Tifway, and this helps compensate for weed pressure.
• Slower emerging and/or covering cultivars such as Yukon, Guymon, and Tifway are susceptible to heavy weed pressure.
• Blackjack suffered the greatest amount of winterkill and Princess the least among seeded cultivars.
• Overall, Tifway suffered the least winterkill.
• At the AU TGRU, Tifway was superior in shoot density, quality, and color.
• At the AU TGRU, Princess had the highest shoot density, color and quality of all the seeded cultivars.
• At Sand Mountain, Princess and Riviera had the highest shoot density and quality of the seeded cultivars.

1. Baltensperger, A. A. 1989. “Registration of ‘Numex Sahara’ bermudagrass.” Crop Science 29:1326
2. Baltensperger, A. A., and J. P. Klingenberg. 1994. “Introducing new seed-propagated F1 hybrid (2-clone synthetic) bermudagrass.” USGA Green Section Record 32 (6) :14-19
3. Baltensperger, A., C. Taliaferro, C Rodgers. 1998. “Seeded bermudagrass gain respect, quality.” Golf Course Management. Oct. 1998.
4. Philley, H.W., and J.V. Krans. 1998. “Turf performance of seeded bermudagrass cultivars.” Golf Course Management Nov. 1998
5. Taliaferro, C.M., R.M. Ahring, W.L. Richardson. 1983. Registration of ‘Guymon’ bermudagrass.” Crop Science 1983 v. 23 (6) p.1219