The Official Publication of the Tennessee Turfgrass Association and the Tennessee Valley Sports Turf Managers Association
The Official Publication of the Tennessee Turfgrass Association and the Tennessee Valley Sports Turf Managers Association
TA B L E O F C O N T E N T S AUGUST/SEPTEMBER 2006
F E AT U R E D A RT I C L E S
12 18 22 26 30 34
8 Recent Event
Phosphites as Fertilizers & Fungicides Applied Research — More than One Way to Kill a Weed Turf Talk — Athletic-Field Dyes for Winter Color Weed Watch — A New Weed in Town
12 Cover Story
Turf Tips — Caution! Spring Dead Spot Programming Ahead Eye on Business — Get to Know TGIF
D E PA RT M E N T S
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From the TTA President, Bill Francis
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A Message from TVSTMA, Al Ray
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News from the TTA
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Ernest Hardison Scholarship Application
38
Calendar of Events
42
Index of Advertisers
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TENNESSEE TURFGRASS
AUGUST/SEPTEMBER 2006
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Turf Talk
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N EF WR OS MF RT OH ME PT RH E S TI DT AE N T BILL FRANCIS
reetings from upper East Tennessee! As we persevere through the “dog days” of summer, I am sure I am not alone when I say, “Come on, October!” With this in mind, I thought it an appropriate time to mention the need for maintaining balance in our professional and personal lives. Now, those of you who know me pretty well would say, “Now, there’s the pot calling the kettle black.” Maybe so, but with each passing year, I do honestly make a concerted effort to improve in this area. Unfortunately, due to the nature of our business, this can be extremely difficult. Demands for top-quality turf are ever increasing, but with prices soaring, many of our budgets are struggling to keep pace. Hence, inevitably we try to do more with less, and all too often, the end result is physical and mental fatigue. One thing I have learned over the years is that you cannot be at your best, day in and day out, if you are not functioning with a fresh mind and body. This can be extra challenging for managers, as we are also responsible for managing our employees’ workload, as well. Tired people make what I refer to as the “little” mistakes. Unfortunately, these are not always as harmless as they sound, but they are always avoidable. Mistakes like figuring an incorrect pesticide rate, forgetting to turn on (or turn off) irrigation programs and missing an appointment or meeting can often be
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very costly. Or better yet, how about an anniversary or birthday! Anyone relate? While I have endured the harmful repercussions of a few of these “little” mistakes, one comes to mind where I was quite fortunate that there were no adverse consequences. To truly appreciate this, you really have to be familiar with the location of our maintenance facility, but I will tell the story anyway. Apparently one evening, during a difficult stretch of summer, a member of my “fatigued” staff (who shall remain nameless) left our entire maintenance facility and compound wide open for an entire night. That’s right — doors wide open, exhaust fan running, lights shining and computers on just like it was a Wednesday at high noon! Obviously, had this incident turned out any other way than it did, there is a fairly good chance that I would not be sharing this story, at least not in this manner! I suppose the lesson that my personal experience has taught me is that it is not always about the amount of hours we put in, but what we put into the hours. My Dad used to tell me that the best indication of a good manager is how well the operation runs in his/her absence. Therefore, afford yourself and your staff the opportunity to step away and recharge. Simply taking a day off, attending an association meeting, playing golf or whatever provides you some R&R may be all it takes. This way you can be certain you will be at your best when your best is most critical.
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The Official Publication of the Tennessee Turfgrass Association and the Tennessee Valley Sports Turf Managers Association
Tennessee Turfgrass is the official publication of The Tennessee Turfgrass Association 400 Franklin Road Franklin, Tennessee 37069 (615) 591-8286 tnturfgrassassn@aol.com Published by Leading Edge Communications, LLC 206 Bridge Street Franklin, Tennessee 37064 (615) 790-3718 Fax (615) 794-4524 Email:info@leadingedgecommunications.com Editor Mr. Bobby Stringer TTA OFFICERS President Mr. Bill Francis The Ridges Golf & CC (423) 913-2276 Vice President Mr. Bob Hogan The Hogan Company (888) 224-6426 Secretary/Treasurer Mr. Bobby Stringer Germantown Country Club (901) 754-7755 Past President Mr. Jeff Case (901) 373-4344 Executive Secretary Mr. Jim Uden (615) 591-8286 TTA 2006 BOARD OF DIRECTORS Mr. Cory Blair Mr. Bart Cash Ms. Monica Lalinde-Cooper Mr. Brad Erickson Ms. Shelia Finney Mr. Roger Frazier Mr. Mickey Lovett Mr. Bill Marbet Mr. Bob McCurdy Mr. Tommy Mittlesteadt Mr. Mitch Parker Mr. Frank Turner TTA ADVISORY MEMBERS OF THE BOARD Mr. Bill Blackburn Mr. Lynn Ray Dr. Tom Samples Dr. Dennis Shepard Dr. John Sorochan
N EF WR OS MF RT OH ME TT VH SE T TMTAA
aury County Parks and Recreation in Columbia served as host for our TVSTMA Middle Tennessee Field Day on June 8. The primary topic of the meeting was a renovation that began on May 13, 2006, to Lindsey Nelson Stadium, a county-operated bermudagrass football field on native clay. Not unlike many municipal and high school fields, it receives heavy play, hosting about 50 football games each fall including pee wee, junior high, freshmen, junior varsity and varsity high school games, as well as spring soccer, a high school graduation and an 8,000-participant band competition in late September. Sound familiar? If it does, you know what kind of issues we face in keeping these facilities up to par. This renovation specifically addressed three key areas in maintaining the integrity of a highly pressured playing surface: grade, soil composition and irrigation. Inconsistent grade on fields at this level is common and results in weak turf and less-than-ideal playability, and in the worst cases, it increases the potential for player injury. Our subject field had typical high and low spots in what was otherwise a generally decent grade, with a strong turf that we hope to hold longer through the season. These inconsistencies, as usual, were most prominent in the areas of the hash marks, crown and sidelines, resulting in poor drainage that perpetuates the problems in these high-traffic areas. The ideal solution — strip, grade and sod or sprig — was not within budget for the project. We opted instead to top grade, a process in which material is added and then graded on the existing turf to fill low spots and remove high ones. The material added was about 200 tons of a mix consisting of 90% sand and 10% topsoil, which we felt would be best for a nativeclay field consistently topdressed with sand over the years. Most of the lowest areas could be corrected while holding the deepest coverage to less than 2". Grow-in has been aided by keeping the cover material loose through frequent aerification and watering, along with modified fertilization. The first fertilizer application contained a pre-emergent conducive to accelerated growth (for any weeds
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brought in along with the added material), followed by ammonium sulfate at one pound N per acre. Two supplemental liquid-fertilizer applications (the second of which contained growth regulator, as per our normal schedule) have produced excellent results. To further our effort to reduce wear by strengthening our turf, we added a calcined-clay product prior to the top grade for its ability to retain moisture and provide air to the roots. To get this product (which has the particle size of USGA sand) into the root zone, we began by pulling 4" cores and topdressing it between the hashes and on the sidelines. Later, when the turf was drier, a vibrating solid-tine aerifyer was used to get the calcined clay deeper. By getting the product as far as possible into the root zone, we are providing air in the areas of a nativesoil field where compaction is always an issue. Most importantly, this (along with subsequent aerifying) will provide a softer, safer playing surface. So far, we addressed moisture management through drainage by correcting grade and by amending the soil. Finally, the field’s irrigation system was modified. The old five big heads down the crown were converted to ten nearer the hashes, providing better, more efficient coverage. This was economically accomplished by simply removing the old heads, teeing off the line down the middle and putting in smaller heads, designed so as to remain with the existing control box. The lines to the new heads were pulled in with a vibratory plow to be less invasive and to avoid later trench indentations. The system is now more aesthetically pleasing and more efficient, but most importantly it is safer, without those huge heads right in the middle of the field, which served to remind me that safety is and should be our number-one priority. Thanks to all who attended and who understand the value of active membership and who exercise responsibility in their leadership roles!
Al Ray
TVSTMA President
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The Tennessee Turfgrass Association serves its members in the industry through education, promotion and representation. The statements and opinions expressed herein are those of the individual authors and do not necessarily represent the views of the association, its staff, or its board of directors, Tennessee Turfgrass Magazine, or its editors. Likewise, the appearance of advertisers, or Turfgrass Association members, does not constitute an endorsement of the products or services featured in this, past or subsequent issues of this quarterly publication. Copyright ©2006 by the Tennessee Turfgrass Association. Tennessee Turfgrass is published bi-monthly. Subscriptions are complimentary to members of the Tennessee Turfgrass Association. POSTMASTER: Send change of address notification to Tennessee Turfgrass Association, 400 Franklin Road, Franklin, TN 37069. Postage guaranteed. Third-class postage is paid at Franklin, TN. Printed in the U.S.A. Reprints and Submissions: Tennessee Turfgrass allows reprinting of material. Permission requests should be directed to the Tennessee Turfgrass Association. We are not responsible for unsolicited freelance manuscripts and photographs. Contact the managing editor for contribution information. Advertising: For display and classified advertising rates and insertions, please contact Leading Edge Communications, LLC, 206 Bridge Street, Franklin, TN 37064, (615) 7903718, Fax (615) 794-4524.
SPECIAL THANKS to the following for their contributions to this project: Lou Warner, Warner’s Athletic Construction (top grading) Bill Marbet, Southern Athletic Fields (topsoil mix, Aerovator and lunch sponsor) Jeff Martin, Quantum Turf Technologies (calcined clay) Bob Elliot, Ewing (irrigation design and materials) Garry Craig, Craig Farms (irrigation installation) Drew Sullivan, Dickens Supply (fertilizer) Dan Marley (Monty’s Liquid Fertilizer) Wayne “Tooty” Lindsey, Maury Co. Parks (absentee host — it’s his field!)
Lou Warner nearing the completion of top grading on Lindsey Nelson Stadium field in Maury County. Photo taken on May 13, 2006.
Attendees at the TVSTMA Middle Tennessee Field Day, viewing the progress of the project. Photo taken on June 8, 2006.
TENNESSEE TURFGRASS ASSOCIATION • TENNESSEE VALLEY SPORTS TURF MANAGERS ASSOCIATION
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T E N N E S S E E VA L L E Y S P O R T S T U R F M A N A G E R S A S S O C I AT I O N
MEMBERSHIP APPLICATION Membership applications can be submitted at any time during the year. For more information, please contact the TVSTMA Office at 1-888-224-6426 or fax your application form to (931) 384-6424. Please print or type the following information as you would like it to appear in the annual directory. Name ___________________________________________________
Title_____________________________________________
Employer_________________________________________________
Type of business_________________________________
Address____________________________________________________________________
P.O. Box_______________________
City__________________________________________ State_______________________
Zip____________________________
Telephone (__________)____________________________________
Fax (__________)__________________________________
Email address _______________________________________________________________________________________________ Additional individuals from same facility requesting membership: Name ___________________________________________________
Title _____________________________________________
Name ___________________________________________________
Title _____________________________________________
Name ____________________________________________________ Title _____________________________________________ Name ___________________________________________________
Title _____________________________________________
Name ____________________________________________________ Title _____________________________________________ Name ____________________________________________________ Title _____________________________________________ Name ____________________________________________________ Title _____________________________________________ Membership Categories: Sports Turf Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $35.00 Coaches & Educators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .$35.00 Sports Turf Student Member (non-voting) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .$10.00 Commercial Member (2 members) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .$100.00 Additional Commercial Members . . . . . . . . . . . . . . . . . . . . . . . . . . . .$25.00 per member
Total
$_________
Signature ________________________________________________________________________________ Please make check payable to: Tennessee Valley Sports Turf Managers Association Please send check and completed form to: Tennessee Valley Sports Turf Managers Association ATTN: Robert Hogan P.O. Box 400 Springfield, Tennessee 37172
P r o m o t i n g B e t t e r a n d S a f e r S p o r t s Tu r f A r e a s i n S o u t h e r n K e n t u c k y, Te n n e s s e e & Northern Alabama
COVER STORY
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TENNESSEE TURFGRASS
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CONTINUED
PHOSPHITES ON GOLF COURSES AS FERTILIZERS AND FUNGICIDES By Erik Ervin, Ph.D., Associate Professor, Turfgrass Science, and David McCall, Research Associate, Turfgrass Pathology, Virginia Tech
Over
the last two decades, Rhone Poulenc (now Bayer Environmental Science) held the
patent for the fungicidal use of the active ingredient (fosetyl-aluminum) in Aliette® and Chipco Signature®. This chemical, when absorbed by plants, is converted to its active form — phosphite. Based on USDA fertilizer research first done in the 1930s, it is known that phosphorus acid (H3PO3) and its salts (potassium phosphite and ammonium phosphite) are also converted to phosphite in the plant.
Research results at a glance • In terms of disease and heat tolerance (of perennial ryegrass and creeping bentgrass), phosphite-fertilizer products perform similarly to phosphite-fungicide products. • Preliminary data indicate that all phosphite products (both fertilizers and fungicides) appear to dramatically suppress algae on golf greens. • It is still uncertain whether phosphite products increase the expression of plant-defense chemicals in bentgrass challenged by Pythium and/or heat stress.
With the recent expiration of the fosetyl-Al patent, a flood of phosphite-based products has hit the horticultural market. Because these chemicals are merely mineral elements, many companies have pursued the much less expensive process of state registration for their products as fertilizers rather than fungicides. Why? Because of the effects of the phosphite ion on plants and microorganisms. Phosphate (HPO42-) is the normal phosphorus form that is used in plant cellular metabolism, playing a critical role in photosynthesis and respiration. Although phosphite (HPO3-) also moves easily throughout plants, it does not bind properly to reaction-catalyzing enzymes, and therefore it does not properly fulfill the plant-growth functions of phosphorus (P). In other words, plants are unable to metabolize or break down phosphite, so it accumulates unused in sink tissues for extensive periods. In fact, in hydroponic culture, plants with access only to phosphite forms of P will die of phosphorus starvation. Consequently, phosphite is regarded as an unacceptable fertilizer form of P. However, phosphite can be still sold as a fertilizer because soil microbes will slowly oxidize it to phosphate. The P in the phosphite will not begin to be plant-available until these tissues die and until the phosphite in these dead tissues becomes part of the soil’s organic-matter pool available for microbial metabolism and transformation to phosphate. So, why is there currently a focus on the benefits of foliar application of phosphites?
TENNESSEE TURFGRASS ASSOCIATION • TENNESSEE VALLEY SPORTS TURF MANAGERS ASSOCIATION
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COVER STORY
Figure 1. Turf quality rated over time at TRC in Blacksburg, VA. Plots were assigned quality ratings on a scale of 1-9, with 9 being the best and 5 being acceptable.
Fungicidal properties of phosphites First, phosphites have been shown to be directly fungitoxic to a certain genera of oomycetes such as Phytophthora (the cause of many common diseases on potato, soybean and many fruits and vegetables) and Pythium (the cause of devastating turfgrass diseases). Phosphite inhibits certain enzyme activities that are essential for fungal energy production and use. Second, phosphite treatment appears to cause the indirect effect of greater expression of plant defense genes. In other words, phosphite-treated plants appear to be able to generate an antimicrobial environment more effectively than those not treated with the chemical. Increased production of phytoalexins (i.e., substances produced by the plant to combat pathogen infection) due to phosphite treatment have been shown to increase disease resistance. None of these responses, however, have been confirmed on turfgrasses challenged by stresses such as Pythium and high temperature. Even so, it has become standard practice to routinely apply phosphite-containing fungicides throughout the summer as a preventative measure against “bentgrass decline,” a complex that primarily has been tied to high rootzone temperature stress. A final factor in the positive responses of phosphite fungicides (in preventing summer bentgrass decline) is the oftenreported greater performance of those products formulated with a green or blue-green pigment (in particular, Chipco Signature®). Reports from field trials conducted by turfgrass pathologists continue to verify the observation that the preventative use of a pigmented fungicide formulation results in greater summer turfgrass quality and disease resistance. In fact, researchers at Clemson University reached the following conclusions: “The improvement in turf quality was due to greener, denser and more uniform turf, not to simply a 14
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‘paint’ effect of the pigment. The non-pigmented fungicides containing only fosetyl-Al had no impact on turf quality … thus the impact of Signature on turf quality does not appear to be related to fungicidal activity or nutritional content, but to the inclusion of pigment in the formulation.” Does inclusion of the pigment (acting as a UV-B protectant) enable the natural defense systems of the turfgrass to remain bolstered against oxidative stress for a longer period? This answer is currently unknown, but the study outlined below will provide some answers.
Our research Given this background information, we have designed growthchamber and field experiments in an attempt to answer the following questions: 1. Do currently marketed phosphite-fertilizer products perform similarly to phosphite-fungicide products in terms of disease and heat tolerance of creeping bentgrass? 2. Does application of phosphite products increase the expression of defense chemicals (phytoalexins and antioxidant enzymes) in bentgrass challenged by Pythium and/or heat stress? 3. What effect does the green pigment added to some of these products (e.g., Signature) have on plant response to these stresses?
Summary of procedures Growth chamber ‘L-93’ creeping bentgrass was grown under optimum greenhouse conditions in calcined clay-filled containers until it was
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CONTINUED uniformly dense and well rooted. Two growth-chamber treatments were used: heat-only (95° F) or heat + pathogen inoculation. Seven days prior to being transferred from the greenhouse to the growth chamber, phosphite treatments were applied. Plants were then transferred to growth chambers for a sevenday period of heat acclimation. Afterwards, plant-tissue sampling, treatment spraying (2nd application 14 days later) and Pythium aphanidermatum inoculation occurred. Wholeplant tissue samples were taken every two days following inoculation for analysis of root mass, antioxidants and phytoalexins as presented below. The treatments were: 1. Water-sprayed control 2. Chipco Signature® 80WG at 4 oz./M; (ai = fosetyl-Al + pigment) 3. Chipco Aliette® 80WG at 4 oz./M; (ai = fosetyl-Al) 4. Magellan™ at 4.1 oz./M; (ai = sodium, potassium and ammonium phosphites) 5. EleMax® at 6 oz./M (ai = potassium hydroxide and phosphorous acid) An actively growing culture of Pythium aphanidermatum was incubated at 27° C for ten days in complete darkness. The resulting pathogens were immediately sprayed evenly over those plants receiving heat stress and inoculum. High humidity conditions (90% RH) were maintained in the growth chamber following inoculation to ensure disease incidence.
Field Various phosphite-based fungicides and fertilizers were tested at three locations in Virginia to determine their impact on plant health during stressful summer conditions and Pythium outbreaks. Sites 1 and 2 were L93 creeping bentgrass greens in Blacksburg, built in 2003 under USGA sand-based specifications. Site 1
was in excellent shape at trial initiation, while Site 2 was not maintained as intensely. Site 3 was a perennial-ryegrass fairway at Waterfront Golf Club with a history of severe Pythium blight outbreaks. Six phosphite-based products were applied every 14 days, beginning in early June and continuing through August. These products were compared against a standard non-phosphite Pythium-control fungicide (Subdue Maxx, mefenoxam) and an untreated control. Since a number of the phosphite products in these field trials contain mineral nutrients, we also used a standard water-soluble fertilizer (Plant Marvel 20-20-20) in all treatments to equalize nutritional inputs on each plot. Percent diseased area, visual turfgrass quality and canopy photochemical efficiency were taken over the 12-week trial period. When striking treatment differences were noted, leaftissue samples were taken to determine levels of antioxidants and phytoalexins.
Figure 2. (Above) Damage caused by Pythium blight in an untreated plot (center), surrounded by effective applications of phosphite-based products and Subdue Maxx (lower left).
Figure 3. (Left) Control of Pythium blight on perennial ryegrass at The Waterfront C.C. in Moneta, VA. Ratings were based on visual estimation of percent blighted foliage within plots.
TENNESSEE TURFGRASS ASSOCIATION • TENNESSEE VALLEY SPORTS TURF MANAGERS ASSOCIATION
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COVER STORY Figure 4.
Figure 5.
Turf quality
In the growth chamber, Pythium control due to phosphite treatments was not complete, with disease levels of 6% to 10% being observed five days after inoculation. However, all of the treatments suppressed disease to a greater extent and at equivalent levels, relative to the untreated control.
Application of phosphite-based products resulted in significantly higher turf quality than the untreated plots at Site 2 (Figure 1). At this site, where initial quality was lower, the phosphite-treated plots appeared to better tolerate summer stress. There was not as much separation in Site 1 as in Site 2 (data not shown). The quality in plots treated with Signature on the Site 2 green declined dramatically in mid- to late July. We believe this was a direct result of tank-mixture incompatibility with soluble fertilizer. After this rating, Signature and the fertilizer were sprayed separately, and no additional phytotoxicity was observed. Turf color was evaluated at each rating date. There were no significant changes in color at either creeping bentgrass location (data not shown). Adding phosphite-based products to the soluble-nitrogen application did not increase overall turf color. However, there were dramatic changes in turf density on Site 2, most likely due to the algae cover (see below). Beginning on June 29, there was a strong correlation between high algae cover and poor turf density.
We were unable to successfully inoculate creeping-bentgrass greens with Pythium. On the perennial-ryegrass fairway, a natural outbreak of Pythium blight was most severe in early August (Figure 3). At this location, all phosphite-based products prevented the development of disease equivalently. When the Pythium outbreak was most severe (August 12, Figure 2), disease pressure was decreased by 93% to 98% and 91% to 95% when treated with phosphite fungicides or fertilizers, respectively. Subdue Maxx provided a 95% reduction in disease on this rating date.
TENNESSEE TURFGRASS
Preliminary data has shown that all phosphite products provided a dramatic reduction in algae cover. On June 29, Subdue Maxx reduced algae cover by nearly 50%, while all other products reduced the algae cover by more than 85%. There did not appear to be a difference between phosphite-based fertilizers (88% to 90% reduction) and phosphite-based fungicides (88% to 96% reduction). Little information has been reported on the suppression of algae with phosphite-based products. Currently, the most commonly used chemical control option is chlorothalonil. While this year’s data showed strong evidence of algae suppression, additional work needs to be done before final conclusions can be made regarding phosphite’s potential as an algae suppressant.
Defense chemicals
Pythium blight
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Superoxide dismutase antioxidant enzyme level increased in the Aliette-treated tissue at one day following Pythium inoculation, relative to the untreated control (Figure 4). Even though there was a trend of increasing levels due to phosphite treatment, after day 1, none of these levels were statistically greater than the control. The levels of the phytoalexin enzyme, coumarin ligase, in response to heat and Pythium inoculation were increased in tissues treated with EleMax, Aliette and Magellan at days 1 and 3 after inoculation (Figure 5). Only EleMax sustained a higher phytoalexin level at five days post-inoculation.
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Conclusions of Research Objectives 1. Do currently marketed phosphite-fertilizer products perform similarly to phosphitefungicide products in terms of disease and heat tolerance of perennial ryegrass and creeping bentgrass? YES. At the two sites where reliable and extensive outbreaks of Pythium blight occurred (Waterfront and growth chamber), all phosphite products provided statistically equivalent disease control. Additionally, it was shown at our TRC green sites that all of the phosphite products provided very good algae suppression. 2. Does application of phosphite products increase expression of defense chemicals (phytoalexins and antioxidant enzymes) in bentgrass challenged by Pythium and/or heat stress? UNCLEAR. We only have growth-chamber results at this point. On certain dates, some of the phosphite treatments resulted in higher defense chemical levels relative to the control, but there were no consistent trends across dates. Given that all phosphite treatments controlled Pythium to the same level, it appears that their primary mode of action in these trials was direct inhibition of the pathogen, rather than indirect protection, by causing a clear increase in defense chemicals within the plant. 3. What effect does the blue-green pigment added to some of these products (e.g., Signature) have on plant response to these stresses? We noted no increases in quality, density, color, disease control or defense-chemical content due to Signature, relative to the non-pigmented phosphite formulations. Acknowledgements: This research was supported by grants from the Virginia Turfgrass Foundation, Virginia Agricultural Council, Bayer Environmental Science, Helena Chemical, Luxembourg Chemical and Grigg Bros. Thanks also to our cooperators at Water’s Edge Golf Club, H.T. Page and Read Harris.
APPLIED RESEARCH
By Scott McElroy, Ph.D., Assistant Professor, Turfgrass Weed Science, and Greg Breeden, Extension and Research Associate, University of Tennessee
ith the massive amount of new information that becomes available every year for turfgrass managers to decipher, it can be difficult for anyone to keep up. New herbicides and herbicide research are no exception. And the old saying “There’s more than one way to skin a cat” applies directly to herbicides, as well. With today’s technologies, there’s definitely more than one way to kill a weed. The following is a review of new herbicides that have been introduced or relabeled for a new turfgrass use in 2005 or 2006. This review is not intended to eclipse the herbicide label itself, so in all cases, please consult the herbicide label directly before using any of these herbicides.
W
QuickSilver T&O Chemical Name: carfentrazone-ethyl Manufacturer: FMC Specialty Products Use Areas: golf courses, sports fields, residential and non-residential turf Turf Safety: all major turfgrass species Target Weeds: broadleaf weeds and moss Use rates: 6.7 fl. oz./acre for moss on putting greens; 1.1 to 2.1 fl. oz./acre for all other areas QuickSilver is a broadleaf active-contact herbicide that was introduced into the turfgrass market before 2005. However, in 2005, it received a supplemental labeling in selected states for a niche use in the turfgrass market — moss control on bentgrass putting greens. 18
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Moss [often referred to as silvery-thread moss (Bryum argenteum)] is an increasing problem on bentgrass putting greens. It is thought to be a result of lower mowing heights and decreased fertility to satiate our need for increased green speeds. Such stressful conditions severely inhibit the ability of the turf to recover from injury, and moss can easily invade. Past research has evaluated various micronutrients, nitrogen applications, fungicides and soaps. While some control was observed with such strategies, all were inconsistent and variable under different weather conditions. QuickSilver has been evaluated by numerous researchers and has been observed to be a very effective product for moss control. Two applications of QuickSilver at 6.4 fl. oz./acre, applied two weeks apart, quickly desiccates moss with no observable injury to bentgrass turf under normal conditions. Remember, though, that moss probably invaded due to the low competitive ability of the bentgrass. QuickSilver will kill the moss, but you must still increase the vigor of the bentgrass. Increasing nitrogen fertility and light verticutting, during the optimal time of the year, could potentially improve overall management of moss contamination. While QuickSilver is great on moss, it is ineffective on algae. Many turfgrass managers group moss and algae together because they are both weird, spore-producing weeds that don’t fit the description of normal weeds we deal with. Evaluations at the University of Tennessee in 2005 have demonstrated that QuickSilver definitely knows the difference between the two species. Lastly, QuickSilver also has specific wording on the label that allows for application to newly seeded or sprigged turfgrass areas. Due to its broadleaf activity, this is an excellent treatment for small seedling broadleaf weeds across the board and allows for an earlier application compared to traditional broadleaf herbicides such as 2,4-D.
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CONTINUED
Certainty Chemical Name: sulfosulfuron Manufacturer: Monsanto Use Areas: golf courses (except greens), athletic fields, sod farms, residential and non-residential areas Turf Safety: bermudagrass, St. Augustinegrass, zoysiagrass, centipedegrass, kikuyugrass and bentgrass (under certain conditions) Target Weeds: yellow nutsedge, green kyllinga, select broadleaf weeds and Poa trivialis Certainty is yet another herbicide on the growing list of sulfonylurea herbicides, which also include Monument and Revolver, among others. Like Monument, it is very effective against sedge species, such as yellow nutsedge and green kyllinga. It also controls a select number of broadleaf weeds; however, this list is limited. Unlike Revolver and Monument, Certainty is labeled for use on numerous turfgrass species other than bermudagrass and zoysiagrass. The addition of St. Augustine, centipede and kikuyu grasses adds more potential flexibility for turf managers who deal with multiple turfgrass species on one golf course or landscapers who manage different home lawn grasses. One unique aspect is that Certainty can also be used to control rough-stalk bluegrass (Poa trivialis) in bentgrass turf. Roughstalk bluegrass is the ugly cousin to annual bluegrass (Poa annua), and due to its perennial nature, few herbicide options are available for its control, especially its removal from cool-season turf. See Certainty’s label directions for specific recommendations. Speaking of annual bluegrass, Certainty, while herbicidally active on annual bluegrass, provides only suppression with single applications. Small annual bluegrass plants can be controlled with Certainty, but larger plants will recover from the injury.
Surge Chemical Name: sulfentrazone, 2,4-D, mecoprop and dicamba Manufacturer: PBI/Gordon Use Areas: golf courses (except tees and greens), athletic fields, sod farms, residential and nonresidential areas Turf Safety: majority of turfgrass species, except centipedegrass and St. Augustinegrass Target Weeds: all broadleaf weeds and yellow nutsedge Use Rates: 2.5 to 4.0 pints/acre
Surge is a new broadleaf herbicide that contains a new herbicide to the turfgrass market, sulfentrazone, which is a protox-inhibiting herbicide that induces the formation of free radicals that destroy plant tissues. Translation: it burns the plant up really fast. Sulfentrazone primarily functions as a contact herbicide with little translocation. As you can tell by the names, sulfentrazone and carfentrazone are in the same family of herbicides. But while carfentrazone has no activity on sedges, sulfentrazone is active on both broadleaf weeds and sedges. While sulfentrazone is active on sedge species, there are potential limitations. Research has demonstrated that sulfentrazone controls yellow nutsedge very well and controls green kyllinga comparable to standard sedge herbicides. However, there is a problem. The amount of sulfentrazone applied in a single application of Surge is less that what has been tested in the past. Sedge control with Surge, therefore, would be classified more as suppression of perennial sedge species or control of small annuals. Despite the reduced amount of sulfentrazone in Surge compared to past research, we have heard numerous reports of satisfied customers using Surge for sedge control. That tells us only that more research is needed to evaluate the use of sulfentrazone for sedge control and the possible beneficial effect of sulfentrazone tank mixtures.
Spotlight Chemical Name: fluroxypyr Manufacturer: Dow AgroSciences Use Areas: golf courses (except tees and greens), athletic fields, sod farms, residential and nonresidential areas Turf Safety: all major turfgrass species Target Weeds: broadleaf weeds Use Rates: 2/3 to 2.5 pints/acre Spotlight is a new broadleaf herbicide for use on all major turfgrass species for control of broadleaf weeds. Spotlight contains fluroxypyr, which acts in a similar fashion to triclopyr (Turflon Ester and also contained in Confront) and other
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APPLIED RESEARCH virginiana) 100%, compared to less than 70% control from two applications of a traditional three-way (2,4-D, mecoprop, dicamba) herbicide.
SedgeHammer
broadleaf herbicides, such as 2,4-D, by functioning as an auxintype herbicide, inducing uncontrolled cell elongation and leaf and stem twisting. Like most herbicides that primarily target broadleaf weeds, tank mixtures are more beneficial because they broaden your spectrum of weeds controlled. However, research conducted in Tennessee indicates that Spotlight effectively controls many broadleaf species, such as white clover (Trifolium repens), ground ivy (Glechoma hederacea) and dandelion (Taraxacum officinale), when applied at 2 pints per acre.
Chemical Name: halosulfuron Manufacturer: Gowan Company Use Areas: golf courses, athletic fields, sod farms, residential and non-residential areas Turf Safety: all major turfgrass species Target Weeds: sedges Use Rates: 0.67 to 1.3 oz/a
Escalade (and other formulations) Chemical Name: 2,4-D, fluroxypyr and dicamba Manufacturer: Nufarm Turf & Specialty Use Areas: golf courses (except tees and greens), athletic fields, sod farms, residential and non-residential areas Turf Safety: all major turfgrass species Target Weeds: broadleaf weeds Use Rates: 2/3 to 3.0 pints/acre
Not a new herbicide, only a new name. Formerly named Manage, SedgeHammer is formulated and labeled for the exact same use. If you know Manage, you know SedgeHammer. Like all SU herbicides, remember to add the appropriate surfactant.
Final thoughts While these are some of the new herbicides that have become available lately, there will be many more in the coming years. Unique herbicides are being developed with safer toxicological properties and new modes of action. So get ready. With new herbicides come new possibilities for weed management.
References Burnell, K.D., F.H. Yelverton, J.C. Neal, T.W. Gannon, and J.S. McElroy. 2003. Control of silvery-thread moss (Bryum argenteum Hedw.) in creeping bentgrass (Agrostis palustris Huds.) golf course putting greens. Weed Technol. 18:560-565.
Escalade is a mixture of the new herbicide fluroxypyr prepackaged with 2,4-D and dicamba. Such a mixture can only increase the spectrum of broadleaf weeds controlled and the activity on more difficult-to-control broadleaf weed species. In our 2005 research, two applications of Escalade at 1.5 qt./a applied six weeks apart controlled Virginia buttonweed (Diodia 20
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McElroy, J. S., F. H. Yelverton, and L. S. Warren, Jr. 2005. Control of established green and false-green kyllinga (Kyllinga brevifolia and K. gracillima) populations in golf course fairways and roughs. Weed Tech. 19:824-829. McElroy, J.S. and G.K. Breeden. 2005. Results of turfgrass weed control investigations. University of Tennessee Institute of Agriculture. Pub no. W114. (available on-line at http://turfweeds.utk.edu).
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T U R F TA L K
Athletic-Field Dyes For
Winter Color By Casey Reynolds, NCSU Turfgrass Research Associate and NC Certified Turfgrass Professional, and Art Bruneau, Ph.D., NCSU Turfgrass Management Professor and Turf Extension Specialist
B
ermudagrass is a primary choice for athletic fields for several reasons. First, its aggressive growth habit from rhizomes and stolons allows it to tolerate the wear and tear commonly associated with highly used athletic fields. Second, bermudagrass is fairly simple to manage. The proper implementation of basic fertilization, irrigation and mowing practices will produce high-quality fields with dense, green turf throughout the summer months. Also, for those fields requiring winter color, bermudagrass can easily be overseeded.
The good and bad of overseeding Overseeding is the process of applying annual or perennial ryegrass during the fall, as the bermudagrass enters dormancy, to supply winter color. The advantage to this, of course, is that by overseeding bermudagrass (a warm-season species) with ryegrass (a cool-season species), you are able to achieve a green field year-round. However, like most things, this decision to overseed comes at a price. Winter overseeding requires a significant amount of effort and money through equipment, materials and manpower. It is a timeconsuming process that not only gets expensive but can also have a negative effect on the overall health of the bermudagrass. For certain situations, like those that exist at professional or college facilities, this is more than likely a fair tradeoff. Managers at these facilities typically have the proper resources in manpower, equipment and budget to not only overseed but also to chemically remove the ryegrass in the spring, as well as re-plant any thin bermudagrass areas through sprigging or sodding. Also, there is usually enough pressure from administration, coaches and other “non-turfgrass managers� to have a lush, green field year-round, that the idea of seeing dormant bermudagrass for seven months by not overseeding is simply unacceptable. There are usually much different circumstances for athleticfield managers at the high school, middle school or municipal 22
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CONTINUED level. Aside from the obvious differences in budget and manpower, there is also much less demand for green fields during the winter months. Sometimes all that is needed is a green field for football playoffs in late fall or baseball in early spring before bermudagrass breaks dormancy. In situations like this, the cost and trouble of winter overseeding is typically not worth the tradeoff. Athletic-field managers in this scenario may decide that dyeing their fields is a suitable replacement to overseeding.
The dyeing alternative Athletic-field dyes can be used for a number of situations. On athletic fields, the most common use is for fall football, spring baseball and special events like graduation, homecoming, etc. Dyes are also used on golf courses to “touch up” poorly overseeded areas, mix with divot sand and to provide color around the clubhouse for special events like weddings. Also, in coastal or extremely hot climates where bentgrass greens simply will not persist, dyes can be used as an alternative to overseeding bermudagrass putting greens. Sod farms have also used dyes to sell dormant warm-season turf in the winter to customers who may want, or require, winter color. Dyes can also be used as an immediate fix or greenup in last-minute cases where special events may arise requiring the use of a green field. A good example of this is fall football playoffs. Often, a field manager or football coach may not know he is hosting next week’s game until his team actually wins this week’s game. It would obviously be impossible to plan overseeding around this; therefore dyeing would be a perfect alternative. The benefits of dyeing an athletic field as opposed to overseeding can include the following: • It is usually less expensive. • You get an immediate effect (as opposed to growing in ryegrass). • It’s less detrimental to the health of the bermudagrass. • You have more flexibility in scheduling. • The dyes are not too affected by rainfall. • No continual maintenance is needed (ryegrass must be mowed, fertilized and irrigated throughout the winter, further adding to cost). • When applied during the growing season, dyes can be mixed with biostimulants for a more pronounced greening effect.
Athletic-field dyes typically cost around $25 to $30 per gallon. A low rate of application may be 2.5 gallons product per acre, with a high rate being 5 gallons product per acre. This brings the cost in product to around $60 to $150 per acre per application. In comparison to the cost of overseeding, this is relatively cheap by the time you factor in manpower, seed, fertilization, irrigation and mowing. However, the decision to dye or overseed in terms of cost must be made on an individual basis. After analyzing the cost, there are a few other factors that must also be considered before you make the decision to dye. These include: • Dye does not result in the bright green, “glossy” color that ryegrass provides. • Dyed fields do not stripe up as well as overseeded fields. The striping effect comes from the light reflecting off the different sides of the leaf blade after being laid down in opposite directions through mowing. • Dye can sometimes stain player uniforms. This is a significant factor that should be considered, given the cost of uniform cleaning and/or replacement.
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T U R F TA L K Using dyes Application rates and frequency of dyes can vary widely, depending on product, desired result, time of year and the quality of the field being sprayed. An application rate of 2.5 to 5 gallons product per acre mixed with water at a 10:1 to 15:1 ratio is usually a good place to start. The product should be applied in at least two different directions to coat both the sides of the leaf blade. So, instead of putting the entire rate down in one application, you have to split the rate into two applications. Spray the first application, let it dry, and then come back the same day to spray the second application in an opposite direction. Two applications of half rates almost always provide a more uniform appearance than one application at a full rate. In addition to spraying half-rates in opposite directions, it may also be a good idea to put down a base coat (full rate) early and then another coat (also a full rate) just prior to your event. For example, in the spring, some baseball coaches will dye their infield two to three weeks prior to the season starting, and they’ll subsequently dye again the day before the opening game. Also, if budget and time permit, they may dye it again halfway through the season, depending on the level of color they want to achieve. In addition to the desired result, the quality of the field plays a role in how much dye is needed. A completely dormant field will need multiple applications at a high rate to achieve a significantly green color, whereas a field that is just entering or exiting dormancy will not require as high of a rate. Also, a field with large bare spots will never achieve a nice green color using dyes. Trying to dye brown dirt with green dye typically results in a bluish-brown color that doesn’t fool anybody! In terms of equipment for application of dyes, almost any type of sprayer will work. You can use backpack sprayers for small areas that need to be patched up, or larger tank sprayers for entire fields. One question that is often asked about dyes is whether they clog up or damage sprayers. The answer is no, not any more than typical herbicides. If you promptly and correctly clean your sprayer after applying dyes, the worst that should happen is the tank may be stained green. If this is a concern, then that is something that should be taken into consideration as part of the decision-making process for applying dyes. Dyes can be an effective and useful tool when implemented as part of an overall bermudagrass management program. They can be used as an alternative to overseeding as well as a quick fix to cover up lastminute concerns. They can also be used to take a field that already looks great to the next level by adding that final touch. More importantly, this approach is based on the implementation of sound bermudagrass-management practices that must be in place long before the day of the big game. Although dyes can be used as a BandAid, they are not as useful at serving as a crutch. After all, dyes will almost never make a bad field look good — they will simply make a good field look better! Acknowledgements: Kevin Robinson, Sports Turf Manager at UNC Chapel Hill Lynn Smith, NC Field Representative for Burnett Lime Company 24
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W E E D WAT C H Rough-Stalk Bluegrass (Poa trivialis) By Scott McElroy, Ph.D., Turfgrass Weed Scientist, and Greg Breeden, Extension and Research Associate, University of Tennessee
here’s a new Poa in town, and this one is bigger, badder and, in some situations, harder to control. Meet Poa trivialis or rough-stalk bluegrass (Photo 1). If you’re like many turfgrass managers, you’ve seen this weed before, but perhaps you just didn’t know what name to call it. Poa trivialis, or as it commonly referred to, Poa triv, is becoming more and more common, infesting tall-fescue turf and, in some minor cases, bermudagrass overseeded with perennial ryegrass. Poa triv is also found in poorly maintained turfgrass areas, such as roughs and roadsides, potentially perpetuating the problem of this weed. No one knows why Poa triv is becoming more of a problem. Some have speculated that it is due to increased Poa triv seed production in the northeastern U.S., in very close proximity to tall fescue and perennial ryegrass seed-production fields. Others speculate that these are native populations that are simply becoming more invasive into certain turfgrass areas. Still others say that it has been here all along, but that we are just becoming more adept at identifying it. There is much debate about whether we are dealing with Poa triv that exists as an annual or as a perennial. Personally, I think
T
that, once established, Poa triv exists as a perennial. The only data I have to back this up is just personal observation. Poa triv seems to show up in the same locations year after year. I also think, however, that new Poa triv populations are being established every year from seed. So, traditional fall preemergence programs targeted at Poa annua control would aid in preventing the spread of Poa triv. Poa triv is easily differentiated from annual bluegrass (Poa annua) and Kentucky bluegrass (Poa pratensis, Table 1). Poa triv is normally lighter green in color, depending on fertilization; it produces a rough red stem; and the seedhead can reach two to three feet tall. Annual bluegrass is lighter green, grows in short, small clumps and produces a white seedhead. Kentucky bluegrass persists more as a dense turf stand (when it survives in Tennessee), has a relatively shorter and greener seedhead than Poa triv and is normally darker green in color.
Controlling Poa triv So now you know what Poa triv is, let’s talk about how to control it. First, Poa triv seems to be more common in wet areas. Ditch banks and other low spots in a landscape are
Table 1. Comparison of identification characteristics of three bluegrass species. Annual bluegrass
Rough-stalk bluegrass
Kentucky bluegrass
Poa annua
Poa trivialis
Poa pratensis
Life cycle
Annual or perennial
Annual or perennial
Perennial
Growth habit
Upright, bunch-type
Upright, bunch to creeping
Decumbent spreading by rhizomes
Produces stolons
No
Yes
No
Produces rhizomes
No
No
Yes
Ligule
Membranous, small coming to small apex
Membranous, similar size to poa annua with no apex
Membranous, large ligule coming to apex
Seedhead/panicle
Small, white
Large, green, reaching 18" to 24" in height when unmowed
Size varies, reaching 12” in height when unmowed
Characteristics
Photo 1: Poa trivialis typically exhibits a clumpy growth habit. 26
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CONTINUED
An infestation of poa annua.
Fescue turf contaminated with poa trivialis.
common areas that Poa triv will infest. In these situations, (foramsulfuron) and TranXit (rimsulfuron) all work well. When improve drainage and avoid over-watering to decrease your Poa applied to dormant turf, Roundup (glyphosate) is also an option. triv infestation. Poa triv is one of the least drought tolerant of Pre-emergence programs that target annual bluegrass control are cool-season grasses, so inducing some mild drought stress will also an effective control strategy for keeping Poa triv in check. decrease your population. Poa triv also tends to be more persistent at higher heights of Final thoughts cut as well, usually above 1". It can tolerate lower mowing You will be hard pressed to find an easy solution for Poa triv heights (obviously, since it is used as an overseeding grass for control. This is a difficult-to-manage weed with few options for bermudagrass greens), but it is more stable as a perennial grass chemical control. Promoting turfgrass health and eliminating in the transition zone at higher heights of cut. environmental problems is your best option for now. Improving your stand of desirable turfgrass species will aid in decreasing Table 2. Potential chemical control scenarios Poa triv, as well. Due to its low drought for Poa trivialis control in cool-season grasses. and heat-stress tolerance, it is very noncompetitive during stressful summer Herbicide Rate Tolerant Turf Application months. Increasing turf density will exacerbate drought and heat stress on creeping bentgrass, Multiple applications may be this turf, thus decreasing your Poa Velocity (bispyribac-sodium) 1.3 to 2.0 oz./acre perennial ryegrass needed for both herbicides. Do not triv population. apply to golf greens. See label for Few selective herbicides are effective creeping bentgrass specific instructions Certainty (sulfosulfuron) 0.25 to 0.50 oz./acre in controlling Poa triv. There are basically two selective herbicides for Poa triv control — Certainty (sulfosulfuron) and Velocity (bispyribacsodium) — and neither herbicide can be used in tall fescue. Effectiveness can vary, and multiple applications are needed for satisfactory control. Both herbicides have special restrictions, so please consult the herbicide label before using. Strategies for using the herbicides are presented in Table 2. For control of Poa trivialis in warmseason grasses such as bermudagrass, the options are much simpler. Monument (trifloxysulfuron), Revolver TENNESSEE TURFGRASS ASSOCIATION • TENNESSEE VALLEY SPORTS TURF MANAGERS ASSOCIATION
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CONTINUED
Developing seedhead of poa trivialis.
Unlike poa annua, poa trivialis does produce stolons.
Literature cited and referenced Liskey, E. 1999. Poa trivialis: friend or foe. Grounds Maintenance. http://groundsmag.com/mag/grounds_maintenance_poa_t rivialis_friend/index.html (last confirmed 29 May 2006) Street, J.R., D.S. Gardner, and P.J. Sherratt. 2005. Annual bluegrass and rough bluegrass control. The Ohio State University Extension FactSheet. SRT-3-05. Throssell, C. and D. Weisenberger. 1999. Poa trivialis control with several herbicide application programs. http://www.agry. purdue.edu/TURF/report/1999/page40.pdf (last confirmed 29 May 2006) 28
TURF TIPS
By Brandon Horvath, Ph.D., and David McCall, Virginia Tech
CAUTION — Spring Dead Spot Programming Ahead!
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CONTINUED pring dead spot (SDS) is a major pathogen of bermudagrass, particularly in its northern range of adaptation where winter temperatures are lowest. SDS symptoms include large, bleached patches of turf that do not green up when the rest of the turf breaks dormancy in the spring. The patches tend to appear in the same general locations from year to year and can be six inches to several feet in diameter. SDS is caused by three pathogens, Ophiosphaerella korrae, Ophiosphaerella narmari and Ophiosphaerella herpotricha. The species that is thought to be the most predominant in the southeastern U.S. is O. korrae. The other two species are mainly present in the Great Plains and central U.S. The SDS pathogens belong to a group of fungi called ectotrophic root-infecting (ERI) fungi that infect the root systems of their hosts and ultimately rot the root tissue. This limits the ability of the plant to take up nutrients and water as growth slows down in the fall, and it is believed to result in the death of the infected plants over the winter. These fungi are most active in the fall and spring when the growth of bermudagrass is slowed and the temperatures and moisture are moderate, favoring the pathogen’s growth. It is believed that infection takes place in the fall, weakening the root system and predisposing the turf to winter injury. This is one possible reason why the disease seems to be more prevalent in the northern range of adaptation. Recovery from the disease takes place from the margins of the patch and any surviving plants within the patch. This process can be slow, and full recovery may not occur until late in the fall.
S
Spring dead spot on a bermudagrass athletic field, showing Poa annua infesting the center of the dead patch of turf.
SDS control Control of SDS requires an integrated approach that uses (1) resistant bermudagrass varieties to limit disease, (2) cultural practices to encourage recovery and survival and (3) fungicide applications to manage disease as it occurs. Research that sheds light on the impact that these different factors play in the resulting severity of SDS has been variable. More research into the practices that affect SDS severity over time and among locations is needed.
Resistant varieties The development of SDS-resistant bermudagrass cultivars has been slow, primarily due to the time-consuming and costly process of field testing. Some
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TURF TIPS research has shown a correlation between cold-tolerant varieties and SDS resistance. Other research showed that infection with SDS pathogens reduced the adaptation to colder temperatures. Presumably, cold-tolerant varieties are better suited to adapt to cold temperatures, and this results in the observed increased resistance to SDS. Breeding of cold-tolerant varieties has resulted in apparent resistance to SDS through the improvement of the plant’s ability to withstand cold temperatures. In general, vegetative varieties Midlawn, Midfield, Midiron, Patriot, TifSport and the seeded varieties Yukon and Guymon have all shown improved resistance to SDS. The most susceptible cultivars include Vamont, Princess 77, Tifway 419, Tifton 10, Tifgreen 328 and many others. Most of this work is the result of research groups at Oklahoma and Kansas State, and it should be noted that one gap in our information about cultivar resistance is whether the results noted for O. herpotricha is similar to results that would be observed with other species of Ophiosphaerella.
Cultural practices Cultural practices that delay the hardening of the bermudagrass in the fall or reduce the winter hardiness seem to increase disease severity. Nitrogen fertility, particularly with fast release sources of N, is one practice that can increase disease severity if applied in the late summer or early fall. There is some debate about the overall effect of late-season fertility and SDS severity that needs to be followed up with continued research. Other cultural practices that have been shown to reduce SDS severity include regular aerification, vertical mowing and thatch reduction. It is important to note that cultural practices alone will not completely manage the disease, and typically, fungicide applications are necessary to achieve sufficient control of SDS.
Fungicide applications Fungicide control efforts have also been extremely variable over time and among locations, making the development of recommendations extremely difficult. Thus, effective control of SDS is costly and not completely reliable. Recent research in North Carolina by Dr. Lane Tredway shows that application timing and method play crucial roles in the success of fungicide applications. Results from this study generally showed that earlier applications of fungicides (August through October) were better than applications made in November, and that split applications were better than single applications. Also, applications made in higher spray volumes (5 gal./1000 sq. ft.) or watered in (with 1/4" irrigation) were more effective than treatments made with 2.5 gallons per 1000 square feet spray volume.
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Symptoms of spring dead spot on a bermudagrass NTEP trial located at the Hampton Roads AREC in Virginia Beach, VA.
The SDS pathogens belong to a group of fungi called ectotrophic root-infecting (ERI) fungi that infect the root systems of their hosts and ultimately rot the root tissue. This limits the ability of the plant to take up nutrients and water as growth slows down in the fall, and it is believed to result in the death of the infected plants over the winter.
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CONTINUED This research also indicated significant differences in fungicides. Rubigan (fenarimol) and Banner Maxx (propiconazole) were the only two products that showed effective control at both test-site locations. Heritage (azoxystrobin) and Eagle (myclobutanil) were effective at a single location. None of the fungicide applications reduced SDS severity to very low levels; in fact, the Rubigan treatments that were rated as best reduced severity by only 66% (Tredway, 2003). Results from Virginia Tech’s SDS trial last year showed that effective treatments were Heritage + Banner, Heritage alone and Eagle. This trial did not include Rubigan, and our future efforts will evaluate this product as well. As seen in other work, success with these fungicides has been variable from year to year and location to location, so caution should be used when making decisions about what fungicide to use for your SDS program. Overall, the best results have been seen with split applications of Rubigan that have either been watered in or applied in a large spray volume. Most other spray programs have been variable in their control of SDS. It is also important to note that effective control of SDS is a multi-year proposition, with control gradually improving over time.
determine if the relationship between cold tolerance and SDS resistance is consistent for different Ophiosphaerella species. We will continue and expand our evaluation of the performance of fungicides under different cultural regimes to develop recommendations that turf managers can use to achieve successful control of SDS.
Future research In the future, we would like to look at the factors responsible for SDS severity and determine what practices can reduce SDS severity. We would also like to evaluate the performance of cold-tolerant varieties to SDS caused by O. korrae to
Spring dead spot symptoms on a Tifway 419 fairway. Note the green tissue in the middle of the patch, indicating that this patch should recover.
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EYE ON BUSINESS
By Chris Hartwiger and Patrick O’Brien, USGA Green Section xperts say the first line in an article is critical to getting a reader’s attention. If the reader is not hooked at that point, he or she is gone. Therefore, we’re going to give you the goods right now. If you consider yourself a turfgrass professional, TGIF must become more than a day of the week or a local hangout. TGIF must become an indispensable resource for turfgrass information.
E
TGI what? TGIF is the acronym for the Turfgrass Information File located at Michigan State University. The best description of TGIF is found on its own website (http://tic.msu.edu/about.html) and is reprinted with their permission below. “Between 1983 and 1992, the United States Golf Association (USGA) Turfgrass Research Program supported the development of the USGA Turfgrass Information File (TGIF). Using the Noer Collection as a foundation, TGIF was designed to systematically inventory published turf research and make the bibliographic information available via a computerized database. The TGIF database is now accessible online through the World Wide Web. With over 100,000 searchable items using over 300,000 keywords, these resources cover the full scope of the turfgrass industry. This database monitors over 320 journals and magazines, research reports and conference proceedings. In addition, the database includes records for extension bulletins, books and book chapters, technical reports, theses and dissertations, webdocuments, published Q & As, scanned golf course plans and video interviews with 34
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selected members of the American Society of Golf Course Architects, sample photographs from the Noer/Milorganite® Division MMSD Image Collection and more! The Turfgrass Information Center, the administrative unit that was created to manage and grow the Turfgrass Information File, has four primary functions: 1. Collect and preserve published and unpublished materials relating to turfgrass science, culture and the management of turfgrass-based facilities, such as golf courses, parks, sports fields, lawns, sod farms, roadsides, institutional grounds and other managed landscapes. 2. Provide and improve precise and structured online access to the collection, as well as available electronic and other turfgrass-related resources, via the World Wide Web. 3. Assist users of the collection and online system, by helping them to identify and locate materials that meet their needs. 4. Provide user workspace and cooperative electronic infrastructure in support of turfgrass scholarship.”
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CONTINUED Technician vs. professional What is the difference between a turfgrass technician and a turfgrass professional? A technician knows what needs to be done and can execute the plan. A professional has the same skills, plus a depth of knowledge behind his or her chosen field. Both technicians and professionals can be highly successful in the turfgrass profession. For those seeking to acquire knowledge and become a turfgrass professional, TGIF must become a friend. There is no other place in the world that contains the breadth and depth of information that can be found online at the Turfgrass Information File.
What can TGIF do for you? The information contained in TGIF is massive. Would you like to view slides taken by famed agronomist O.J. Noer? Interested in a Green Section Record article from 1921, 1971 or 2001? They are all available at TGIF. The number of articles that can be searched online continues to grow, too. Do you remember attending a field day at NC State
University in which a researcher discussed a trial on plant growth regulators, but you can’t remember the details? Go to TGIF and look for NC State Field Day Proceedings. Find the article(s) and review them online. If they are not searchable online, request a copy from TGIF for delivery by mail or fax. TGIF is your onestop shop for turfgrass information.
Is TGIF right for you? TGIF is an invaluable resource for every turfgrass professional. The cost for individuals is only $100 per year or $500 for lifetime access. Dr. Peter Cookingham and the staff at the Turfgrass Information File at Michigan State University have ambitious goals for increasing the number of fully searchable online articles and to one day eliminate the access fee. Industry support for TGIF is needed if these goals are to be met. Any time is a good time to sign up for TGIF. Sign up information is available at http://tic.msu.edu/subscribe.html. Get to know TGIF. Acquire knowledge. Your career as a turfgrass professional will reap the rewards.
TENNESSEE TURFGRASS ASSOCIATION • TENNESSEE VALLEY SPORTS TURF MANAGERS ASSOCIATION
35
N E W S F R O M T TA Who Would You Select As TTA Professional of the Year? Do you know an outstanding turfgrass professional in Tennessee who deserves the recognition of his or her peers? If so, now’s the time to let the TTA know who you believe should receive one of the association’s highest honors — the TTA Professional of the Year Award — at the TTA Annual Conference and Tradeshow this coming January. Please take a moment to mail in the nomination form below. Nominees will be reviewed by the TTA Awards & Scholarship Committee, which will make a recommendation for approval by the TTA Board of Directors. Nominations must be postmarked no later than October 1, 2006.
TTA Professional of the Year Nomination Form Person Being Nominated: __________________________________________________________________________________ Person Making the Nomination: ______________________________________________________________________________ Reason for Nomination: ____________________________________________________________________________________ ________________________________________________________________________________________________________ ________________________________________________________________________________________________________ Nominations must be postmarked no later than October 1, 2006. Please mail nominations to: Tennessee Turfgrass Association 400 Franklin Road Franklin, TN 37069
ERNEST APPLICATION SCHOLARSHIP APPLICATION NERNEST E W S HARDISON F R O M MEMORIAL T H E T TSCHOLARSHIP A PLEASE TYPE OR PRINT NEATLY SECTION I: PERSONAL INFORMATION
NAME: HOME MAILING ADDRESS:
CAMPUS MAILING ADDRESS:
PHONE: (HOME)
PHONE: (CAMPUS)
SECTION II: EDUCATIONAL INFORMATION
INSTITUTION NAME: GRADUATION DATE: OVERALL GPA: ADVISOR: ADVISOR ADDRESS:
MAJOR: MAJOR GPA: PHONE:
SIGNATURE OF ADVISOR: (NOTE: HANDWRITTEN SIGNATURE OF ADVISOR MUST APPEAR ON THIS FORM)
ADVISOR’S COMMENTS:
SECTION III: BACKGROUND INFORMATION
NAME(S) AND RELATIONSHIP(S) OF ANY RELATIVES ASSOCIATED WITH THE GOLF OR TURFGRASS INDUSTRY: NAME(S) AND RELATIONSHIP(S) OF ANY RELATIVES WHO ARE MEMBERS OF THE TENNESSEE TURFGRASS ASSOCIATION: HAVE YOU PREVIOUSLY RECEIVED A TENNESSEE TURFGRASS ASSOCIATION SCHOLARSHIP? IF YES, PLEASE LIST YEAR AND AMOUNT: WHAT ASPECT OR CAREER OPPORTUNITY WITHIN THE TURFGRASS INDUSTRY MOST INTERESTS YOU? SECTION IV: ADDITIONAL REQUIREMENTS
PLEASE INCLUDE THE FOLLOWING WITH YOUR APPLICATION: 1 A COPY OF YOUR RESUME 2 A LIST OF REFERENCES (MINIMUM OF 3) 3 AN ESSAY (300 WORDS OR LESS) DESCRIBING: • YOUR REASONS FOR REQUESTING THIS SCHOLARSHIP • YOUR REQUIREMENT FOR AND SOURCES OF FINANCIAL SUPPORT FOR COLLEGE AND RELATED EXPENSES
APPLICATIONS MUST BE POSTMARKED NO LATER THAN NOVEMBER 1, 2006. AWARDS WILL BE PRESENTED AT THE ANNUAL TENNESSEE TURFGRASS ASSOCIATION CONFERENCE IN JANUARY 2007. PLEASE SUBMIT YOUR APPLICATIONS TO: TENNESSEE TURFGRASS ASSOCIATION 400 FRANKLIN ROAD FRANKLIN, TN 37069
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TENNESSEE TURFGRASS
AUGUST/SEPTEMBER 2006
Email TTA at: tnturfgrassassn@aol.com
I N D E X O F A DV E RT I S E R S
CA L E N DA R O F E V E N T S
Bayer Environmental Science www.bayerprocentral.com . . . . . 28 Burlingham Seeds www.burlinghamseeds.com . . . . . . . . . . . . 29 BWI Companies www.bwicompanies.com . . . . . . . . . . . . . 7, 31 Commercial Discount Parts www.cdpparts.com . . . . . . . . . . 17 Covermaster, Inc. www.covermaster.com . . . . . . . . . . . . . . . . 40 Dixie Turf and Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 E & S Soil and Peat www.eandssoil.com . . . . . . . . . . . . . . . 37 Ewing Irrigation www.Ewing1.com . . . . . . . . . Inside Back Cover Greenville Turf & Tractor www.JohnDeere.com . . . . . . . . . . . . 3 Harrell’s www.harrells.com . . . . . . . . . . . . . . . . . . . . . . . . . 37 John Deere Landscapes www.johndeerelandscapes.com . . . . . 25 K-Rain Manufacturing Corp www.krain.com . . . . . . . . . . . . 33 Keeling Company www.keelingcompany.com . . . . . . . . . . . . . 35 Mayes Turf Machines, LLC www.mayesturfmachines.com . . . . 27 Mid Tenn Turf www.midtennturf.com . . . . . . . . . . . . . . . . . . . 40 Pennington Seed, Inc. www.penningtonseed.com . . . . . . . . . . . 5 Princeton Delivery systems, Inc. . . . . . . . . Inside Front Cover
August 8, 2006
MTGCSA Equipment Demo Day Location: The Legends Club
August 10, 2006
University of Tennessee Turfgrass Field Day and East TN TVSTMA Field Day Location: University of TN, Knoxville, TN
August 22, 2006
Tennessee Green Industry Field Day Location: McMinnville, TN
August 31, 2006
West Tennessee Research Field Day Location: West Tennessee REC, Jackson, TN
October 6–8, 2006
The International Lawn, Garden & Power Equipment Expo Location: Louisville, KY
October 10–14, 2006
NRPA Congress & Exposition (National Recreation and Parks Association) Location: Seattle, WA
October 16, 2006
ETGCSA Scholarship and Research Tournament Location: Green Meadows CC, Alcoa, TN
October 17, 2006
MAGCSA Scholarship & Research Tournament Location: to be announced
November 7, 2006
MTGCSA Scholarship & Research Tournament Location: Belle Meade Country Club
January 15–17, 2007
41st Annual TTA Conference & Trade Show Location: Marriott Cool Springs
www.piggy-back.com
Prosource One www.prosourceone.com . . . . . . . . . . . . . . . . 36 Regal Chemical www.regalchem.com . . . . . . . . . . . . . . . . . . 21 Smith Turf & Irrigation www.smithturf.com . . . . . . . . Back Cover Southeastern Turf, LLC www.southeasternturf.com . . . . . . . . . 28 Sur-Line Turf, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Syngenta www.syngentaprofessionalproducts.com . . . . . . . . . . . 41 Tennessee Crop Improvement . . . . . . . . 17 www.superiorseeds.org
The Scotts Company / Landmark Seed . . 11 www.scottsproseed.com
Turf Mountain Sod . . . . . . . . . . . . . . . . . 42 www.turfmountain.com
Turf Specialties, Inc. . . . . . . . . . . . . . . . 37 Turfgrass America . . . . . . . . . . . . . . . . . . 7 www.turfgrassamerica.com
United Agriculture Services of America . . . 23 www.uas-cropmaster.com
Winstead Turf Farms Inc. . . . . . . . . . . . . 39 www.winsteadturf.com