A Question about St. Augustinegrass Cultivars

Q: Reports on this new St. Augustinegrass called Palmetto are flooding our newspapers and radio stations here in the Charleston SC area. I understand that Texas has many sod producers also growing this grass and that it is doing well in the Houston area. Please tell me what you know about this grass. Presently I have Raleigh and have severe problems with brown spots and areas that never greened up after this past winter.

A: Your question stimulated the PLANTanswers experts to do some research since we are not personally familiar with the Palmetto. Here are several articles written on Palmetto -- one by a researcher in Florida and one by the president of Sod Solutions, the Palmetto distributor. See what you think.

NEW ST. AUGUSTINE GRASS
by John L. Cisar, Ph.D.
University of Florida -- IFAS

St. Augustinegrass (also known as Charlestongrass in South Carolina) is often the most popular choice for lawn throughout the southern United States. This is especially true in coastal regions where damaging cold temperatures are moderated by oceanic climatic conditions. St. Augustinegrass. being native to the Caribbean, Africa and Mediterranean regions, is best adapted to sub-tropical climates. However, a new cultivar named Palmetto is finding its niche in the trade. I will introduce it in this article and discuss the various traits of the group as a whole.

Cultivars
St. Augustinegrasses are mainly propagated vegetatively. Therefore, breeding of new varieties takes a considerable length of time, which is one of a variety of reasons for their slow appearance in the marketplace. A key factor is the long and vigorous testing that is required before release to confirm and understand both positive and negative traits. Floratam, the combined 10-plus year efforts of both the University of Florida and Texas A&M (that's why it is named Flora-T&M) is a highly successful example of breeding program efforts. As a matter of fact, grasses, many of the semi-dwarf types have excellent shade tolerance relative to coarse-type St. Augustinegrasses and other warm-season grasses. In areas where I have planted St. Augustinegrass, it has performed very well in shade.

We also know that the semi-dwarf varieties do not possess chinch bug resistance, and those planting this grass will need to use insecticides to control infestations when they occur.

Palmetto is available as plugs or sod. Recently, we successfully planted in the plugs in a very shady area, and in the past month have planted it as sod at the Ft. Lauderdale Research and Education Center in South Florida. It has knitted in quickly and very well, despite poor establishment conditions (cool and short day lengths). We plan on conducting some cultural trials with this grass as it becomes well established. There have been anecdotal claims for deep rooting with Palmetto. Although beyond the scope of our study, a good test would be to compare this grass for its rooting capability with similar semi-dwarf among St. Augustinegrasses for a variety of growing conditions. Whether you choose a standard such as Floratam, or take a chance on Palmetto -- "the new kid on the block" -- it's important to recognize their relative strengths and weaknesses to aid in the selection of the most suitable variety for your site. Moreover, do not overlook St. Augustinegrasses for your lawn, as they really can perform in a wide range of sites formerly thought of as sites for centipedegrass, zoysiagrass, or bermudagrass. My suggestion is to give them every consideration.

John L Cisar Ph.D., is an associate professor of turfgrass management and water at the Fort Lauderdale Research and Education Center, University of Florida.

PALMETTO ST. AUGUSTINEGRASS
Information furnished by Tobey Wagner, President of Sod Solutions

Palmetto was discovered and developed on a sod farm near Daytona Beach, Florida. The cultivar has been tested under "real life" conditions on the sod farm and in practical homeowner situations. Palmetto is not a miracle grass, but the combination of characteristics demonstrated is unequaled. As detailed below, the versatility of Palmetto will be a valuable tool in the Texas landscape.

The most notable attribute when examining a field or plot of Palmetto is it's deep, vivid color and soft texture. Its visual appeal alone makes it a superior choice in comparison to other strains now available. However, just as importantly, Palmetto has proved to be an exceptional performer in both sun and shade. Often in designing a landscape, a grass is required that will thrive in both full sun and shade. This problem becomes more exaggerated as landscapes mature, and shady areas increase when trees grow larger. Palmetto is the most versatile St. Augustine available to address these changing needs.

Cold snaps in northern and central Texas can severely damage or kill Raleigh St. Augustine. Palmetto has withstood temperatures near 5 degrees F. in South Carolina, Georgia, and Texas with no significant damage. In Jacksonville, Florida and Charleston, South Carolina Palmetto has remained green in areas where other St. Augustines have gone dormant. This past winter Palmetto remained green in the Tampa Bay, Florida area after two nights of heavy frosts. Floratam and Raleigh St. Augustine both sustained significant browning out damage in the same area.

Another important characteristic of Palmetto is its deep, massive root system. This trait could reduce the frequency of irrigation needed once established. In addition, this root system causes Palmetto to transplant well, and establish quickly. It is often desirable to plant a landscape that gives the appearance of a mature lawn shortly after installing.

Additional information or inquires about Palmetto can be directed to Tobey Wagner at (803) 849-1288 or the Internet website address at: www.palmetto-grass.com.

I think the statement made by the Florida researcher which says: "There are many choices among St. Augustinegrasses for a variety of growing conditions. Whether you choose a standard such as Floratam, or take a chance on Palmetto -- "the new kid on the block" -- it's important to recognize their relative strengths and weaknesses to aid in the selection of the most suitable variety for your site." pretty much sums up my feelings about this situation without actually have grown the grass. From what I can understand from my reading, Palmetto is a selection by Elmer Kirkland from a stand of native St. Augustine grass in the summer of 1988. It has always been my contention that God is a better plant breeder than most that I have met (especially here in Texas!!) so I will give Him credit until I find out otherwise. However, I worry when I see statements that Palmetto is more drought-tolerant than Floratam without research data to support such a claim. I am promoting Floratam in the San Antonio area and have research data to support that it is the most drought tolerant of the St. Augustinegrasses EVER tested. I have the following data to substantiate the claim:

FLORATAM ST. AUGUSTINE GRASS FOR SHADY, MODERATE TRAFFIC AREAS

Floratam St. Augustine grass was released by the Florida and Texas Agricultural Experiment Stations in 1972 as a SAD virus and chinch bug resistant selection. It has since been observed to be brown patch tolerant. Like other Florida types, Floratam is a vigorous, coarse textured St. Augustine grass variety. Stolons of Floratam are large, purplish-red in color (demand this characteristic when purchasing sod) with internodes averaging 3 inches in length. Leaf blades are wider and longer than common St. Augustine grass. According to James Beard, TAEX Turf Researcher, tests at A&M concluded it is the most drought-tolerant of all St. Augustine grasses.

Floratam is not as cold tolerant as the common type found in Texas so preconditioning by use of Winterizer fertilizer (3-1-2 or 4-1-2 ratio) in the fall (October) is CRITICAL. Floratam may suffer freeze damage in areas north (cold) and west (dry) of San Antonio. These areas should use Raleigh St. Augustine because of cold tolerance and St. Augustine Decline. Floratam also lacks the degree of shade tolerance that other St. Augustine grass varieties possess but filtered light through live oak canopies offer the ideal growth environment.

A study of the drought tolerance of grasses entitled: " Comparative Intraspecies and Interspecies Drought Resistance of Six Major Warm-Season Turfgrass Species" by S. I. Sifers and J. B. Beard, Texas A&M University. Their findings were: Four years of field drought resistance studies have been completed on a modified sand root zone. In the fourth year of the study, 29 bermudagrass, 2 seashore pespalum, 2 buffalograss, 8 St. Augustinegrass, 6 centipedegrass, and 11 zoysiagrass cultivars were subjected to 158 days of progressive water stress with no supplemental irrigations applied and less than 7.5 cm of natural rainfall. Degree of leaf firing was used as an indicator of dehydration avoidance and post-drought shoot recovery was used as the indicator for drought resistance. Significant drought resistance differentials were found across the cultivars and among the species. Results were consistent with the first three years of this study among the bermudagrass, seashore pespalum, St. Augustinegrass, and buffalograss cultivars. Among the centipedegrass cultivars only Oklawn fully recovered. Leaf firing of all zoysiagrass cultivars was in excess of 50 percent. All recovered, except Meyer at 20 percent and Belair at 45 percent after 30 days. Excellent dehydration avoidance was seen in Floratam and Floralawn St. Augustinegrass. There were large variations in drought resistance among the five St. Augustinegrass cultivars. Floralawn and Floratam showed high green shoot recovery. They showed less than 50 percent leaf firing after 34 days of drought stress and recoveries of over 90 percent. However, Texas Common and Raleigh St. Augustinegrass as well as Prairie buffalograss showed over 98 percent leaf firing and less than 20 percent recovery. The performance of Floratam and Floralawn was excellent throughout the study in terms of shoot color, turgidity, and uniformity. They were comparable to 609 Buffalograss.

We can only hope that Palmetto does out perform Raleigh (cold tolerance) and Floratam (shade tolerance) -- time and testing will tell.

I was very concerned (as far as the San Antonio area is concerned) about the statement: "We also know that the semi-dwarf varieties do not possess chinch bug resistance, and those planting this grass will need to use insecticides to control infestations when they occur." Chinch bugs and brown patch fungus is a severe problem here -- more so than anywhere else in the state. Floratam is resistant to chinch bugs and tolerant to brown patch (so far the ONLY St. Augustine which is) so it is, presently the grass of choice for shady areas in San Antonio.
BE SURE to visit the Palmetto WebSite at: http://www.palmetto-grass.com./. It is well done and has lots of information.

I hope all of this information has been helpful. I wish to thank Dr. James McAfee, Texas Cooperative Extension, Dallas Research and Extension Center, for his input into this response.