Virginia Turfgrass Journal - July / August 2011 by leadingedgepubs

Virginia Turfgrass Council / P.O. Box 5989 / Virginia Beach, VA 23471 / ADDRESS SERVICE REQUESTED

Journal of the Virginia Turfgrass Council | July/August 2011

14 14 Cover Story

Weathering the Storm – Bermudagrass Winterkill of 2010–11 18 Applied Research

Soil Texture, Wetting Agents and Water-Repellent, Sand-Based Sports Fields

24 Turf Talk

Managing Putting Greens under Stress

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24 DEPARTMENTS 6 P resident’s Message

from Melissa Reynolds

8 Director’s Corner

from Tom Tracy, Ph.D.

10 E ditor’s Perspective

from Mark Vaughn, CGCS

12 VTF Report

from Betty Parker

30 Turfgrass Calendar 30 Index of Advertisers

President’s Message

Constancy through

Melissa Reynolds VTC President

Turmoil

How

many tumultuous world events have transpired so far this year? For most of us, the headlines are still fresh, even vivid, in recall:

• January 8, 2011 — The shooting attack of Rep. Gabrielle Giffords (D–AZ). • March 11, 2011 — Northern Japan, 9.0 magnitude earthquake (4th largest earthquake in the world) and tsunami, resulting in more than 15,000 lives lost, 9,093 lives missing and critical conditions for the Fukushima Dai-Ichi nuclear power plant. • April 28, 2011 — The tornado that struck Tuscaloosa, Alabama, claiming 295 lives and leaving the city stricken. • May 2, 2011 — Terrorist Osama bin Laden was killed in Abbottabad, Pakistan, by U.S. Seal teams. • Week of May 16, 2011 — Historic flooding of the Mississippi River. • May 22, 2011 — The tornado that struck Joplin, Missouri (town of 50,000 citizens), resulting in at least 120 lives loss, numbers of missing residents and much of the town obliterated. Yet, with the above world events swirling in an apparent unending cycle before us through all media types, creating turmoil, there are constants in our lives. By and large, the majority of us in this part of the world, in this state and region, have the blessings of family, friends, work and other valuable, treasured relationships. In our industry, despite the prevailing economic climate, we enjoy the “constant” promotion of our work, our livelihood, through our involvement with varying trade associations. Consider the Virginia Turfgrass Council, a constant force in promoting our industry. As an organization, the Council constantly maintains a proactive stance in our efforts to identify legislation that may either hinder or promote our industry overall. The annual January “turmoil” of proposed legislation requires nearly daily monitoring and contact activity — all with an eye toward providing a constant watch for the benefit for the turfgrass industry. Other constants — training classes for pesticide recertification are planned and executed; two Field Day activities are slated this year; the Bob Ruff Research Golf Tournament is planned and held for the benefit of the Virginia Turfgrass Foundation, thus promoting the funding of research for the turfgrass arena of work; and, throughout the year, the VTC Conference and Trade Show is at the forefront of planning for each January event. Now, consider anchoring yourselves, your company and your employees to the constant value of an organization such as the Virginia Turfgrass Council — consider membership, volunteering and participation. c

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Director’s Corner

CONSIDER THE

ALTERNATIVES Tom Tracy, Ph.D. VTC Executive Director

teve Slominski, a VTC Board member, got me reading Predictably Irrational, a book about forces that shape decisions. While I am still digesting the book’s intricacies, one point made in the early pages stands out: “Humans rarely choose things in absolute terms… Rather, we focus on the relative advantage of one thing over another, and estimate value accordingly.” I propose the choice to belong to the VTC is one decision that is valuable and has advantages over the alternatives. Look at the work we do educating decision-makers about the value of turfgrass and about the importance of Virginia’s turfgrass industry. What is the advantage of this education? I answer that question by considering the alternative — having laws and regulations for our industry made by people who operate from ignorance. The policies they would enact would not be based in science but would be impractical, would actually harm the environment and would punish honest, hard-working individuals. Imagine if you were unable to apply any fertilizers or pesticides to your properties. That scenario is not far-fetched and must be weighed against the small amount you pay to belong to the Virginia Turfgrass Council to be your advocate. Look at the work we do influencing specific legislation. Such work has never been — and can never be — a substantial part of our activities because we are a 501-C5 corporation. (And, as we educate decision-makers, increase our membership, promote proper turfgrass management and build bridges with specialinterest groups, the need to get involved with specific legislation diminishes.) What is the value of this work? Consider the alternative. A bill introduced at the 2011 General Assembly would have allowed each of the localities within Virginia to regulate fertilizer usage. Imagine, if you will, the tremendous burden of turfgrass professionals having to comply with conflicting fertilizer-usage regulations in adjacent cities. The onus of that task easily outstrips our annual membership dues. I could continue with example after example, but the point is made. The relative value of belonging to the VTC far exceeds the alternatives. We work for you. We fight for you. c

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Virginia Turfgrass Journal is the official publication of The Virginia Turfgrass Council P.O. Box 5989 Virginia Beach, VA 23471 Office: (757) 464-1004 Fax: (757) 282-2693 vaturf@verizon.net PUBLISHED BY Leading Edge Communications, LLC 206 Bridge Street Franklin, Tennessee 37064 (615) 790-3718 Fax: (615) 794-4524 Email: info@leadingedgecommunications.com EDITOR Mark Vaughn, CGCS VTC OFFICERS President Melissa Reynolds Dura Turf Service Corp. (804) 233-4972 Vice President Frank Flannagan Belmont Golf Course (804) 501-5993 Treasurer Brian Vincel, CGCS Spring Creek Golf Club (434) 566-2580 Past President Rick Viancour, CGCS Golden Horseshoe Golf Club (757) 220-7489 VTC DIRECTORS Fred Biggers, CGCS Gil Grattan Vince Henderson Rick Owens, CGCS Marc Petrus Steve Slominski Steve Smith Scott Woodward VTC ADVISORY MEMBERS OF THE BOARD Mike Goatley, Ph.D. (Chair) Shawn Askew, Ph.D. Jeffrey Derr, Ph.D. Erik Ervin, Ph.D. Rajandra Waghray, Ph.D. Rod Youngman, Ph.D. EXECUTIVE DIRECTOR/ DIRECTOR OF PROGRAMS Tom Tracy, Ph.D. (757) 681-6065 VIRGINIA TURFGRASS FOUNDATION Betty Parker (757) 574-9061

Editor’s Perspective

GUBMENT’S Mark Vaughn, CGCS Virginia Turfgrass Journal Editor

DAM SAFETY ACT

So...

I was settin’ on a log down here in Southside the other day, chewing on a piece of straw, contemplating the meaning of life and worryin ‘bout what we gonna do with this excess money we had layin round. Dat golf biness done been so good last few years, we just plum flush with cash — you boys and girls know what I speak of. Well sir, I was watchin them Canadian geese organically fertilize my lake banks and fishing docks the little boys and girls like to set on to fish when I seen a flash out the corner of my eye. The sun was reflectin across the windshield of a fancy pick’em up truck headed my way, and I said to myself, I said self, “This here must be a stranger, ‘cause there ain’t many new trucks in this part of the woods.” When he got close enough, I notice he had one of them funny license tags on the front. Well sir, he bounced out of that truck sportin a big smile like we was a best friends. Don’t know about you’uns, but I always get a little nervous when total strangers act like we been buddies forever. He said he was Jim, and he was here representin something called the DCR. Well now, I got a little more nervous because he was working for one of them companies that don’t need no name, just initials. Kinda like FBI, CIA, IRS, FDIC, USGA, etc. He commenced to tellin me that he was from the gubment and wanted to know if I ever heared of the Dam Safety Act. I told him I heared a lot about safety from one of them other companies that’s just initials, something called Usher or Osher, but they never used cuss words like damn. For some reason he just laughed, but then that big smile started to disappear, and he pulled out this passel of official lookin papers.

He said the dam on our little 6.5-acre lake was over 25 feet tall from the top of the dam to the crik bed at the back and was gone have to be regulated. I kinda smiled, ‘cause now I had one on him. I says, “Yes sir, I knowed about that because Chris, our environment guy across the road over where they makes them Goodyear tires, told me our dam had been permitted years ago. And don’t our dam look nice? All mowed down front and back, no trees or muskrat holes. Spillway lined with rock. That dam been here since before this golf course — pert near 65 years. And I’ve seen some frog stranglers roll through this valley, and this old girl held up just fine.” Well now, that grin reappeared (although it wadn’t near friendly as it was the first time), and that feller said, “We got us some new regulations, fresh from Richmond. We gonna protect the citizens of this great Commonwealth from

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dangerous damn owners like you. Don’t you wanna protect your neighbor from floods?” Well sir, first I asked him not to cuss at me, and then I says, “Sure, what could be more Virginian than chivalry and not wantin to kill your neighbor” (with apologies to General Lee whispered under my breath). Then I asked this feller, Jim, I says, “They been having problems with dams down near Richmond? You boys oughta go after them lawbreakers and put them under the jail. But them people like us that ain’t causin no problems, I don’t see no need in new regulations.” He said, “Son, that ain’t how the gubment works. We passin new laws everyday to keep you citizens from hurtin, maimin and, yes, even killin each other. It’s our job to look ahead and protect you from yourselves.” He left me with them papers, and somethin called a “web address” to study. He suggested I call Chris and commence gettin our place in line. Well sir, I called ol’ Chris, and that boy got fired up. Called one of them fancy environmental engineering firms to start studyin and give us some options. They rolled in with their fancy laser measuring sticks, some little boxes they said had “GPS” in them (I got a little nervous when they started with them initials again, but Chris said it was fine) and

a little boat that used something called “sonar measuring.” Then one day, they even pulled in with this rig lookin like they was a goin to drill a well. They punched four little holes in my dam, but them fellers never hit water. I coulda told them that. Chris said after they did some cypherin, they was comin back with three choices on what we could do about them new regulations. In the meantime, I got my daughter to look up that “web address,” and I commenced to readin them new laws word for word. Then I found it! I called Chris up all excited and says, “These gubment laws have something called an exemption for agriculture. We is home free!” Well sir, Chris got all excited, too. At least until he called Richmond. He calls me back and tells me we ain’t agriculture. I says, “Wait a minute, Chris. This here degree I got hangin on the wall from that fancy university says School of Agriculture. Them people in Richmond which helps us with that lobbyin stuff like takin them law fellers out to eat and playin golf and genly bein nice to them is called the Virginia AGRIBUSINESS Council. And my grass crop, ifin it don’t have no water, it dies, and I don’t have no customers. This ain’t just pretty water like some of them ponds out there.” Chris said it didn’t seem to matter to the gubment and suggested I read a little further. So, I commenced to readin again and found out if the gubment owned our pond, it would be exempt from the regulations that the gubment created. So’s I called Chris again and says, “Our problem is solved. We’s gonna be sharecroppers. We give our lake to the gubment, and they lease it back to us.” Chris didn’t think too much of that one. In a few weeks, they was through cypherin and came with our choices. Option #1 was install a 25-footdiameter spillway pipe to handle the storm flow. A WHAT diameter pipe??? That’d be about the size of one of them holes they dug underneath that water over there in England to run them railcars through.

Chris got me on the phone with one of them engineers to help lower my blood pressure. “Just what kinda storm we talkin ‘bout here, missy? 100 year, 500 year, Noah’s Ark?” She explained they didn’t use no old data like that. No, this was a model developed by them Army Corps of Engineers using what they call a HECRAS to predict the PMFE. Yessir, I got nervous again. Don’t know what HECRAS stands for, but I learned PMFE is Probable Maximum Flood Event. When I asked her to put it in plain language an ol’ dumb redhead could understand, she said, “Oh, about 38 inches in a 24-hour period.” When I got through laughing, I noticed she wasn’t. She was just as serious as anthracnose in August. Option #2 was to encase the dam in some impervious material so when the Ark went over it, it would still be standing. And Option #3 was to lower

the barn door (or shorten the mule’s legs) so we wouldn’t have to deal with the gubment anymore (at least until them fellers in Richmond came up with some new laws). I asked Chris what this was gonna cost. He said Options 1 and 2 were easily $600,000 to $700,000 dollars each. Option 3 (lowering the dam to under 25') would still be expensive, but probably less than half of the other choices. Guess which option is leading the voting? Guess what our lake is going to look like when we are done? Oh, my employer has already spent about $50,000 for them fellers to give us this good news. Still think the VTC, VGCSA, the other allied associations and all the fine fellers and ladies we send to Richmond on our behalf don’t need your support? For more info: http://www.dcr. virginia.gov/dam_safety_and_ floodplains/. c

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VTF Report

The 2011 Bob Ruff Jr. Research Golf Classic Betty Parker VTF Manager

This

year’s annual golf tournament to raise funds for turfgrass research was held on June 7 at Wintergreen Resort. Fred Biggers once again generously served as the hosting superintendent to this 27-hole event. Besides being a great venue for playing golf, the tournament is always a wonderful time for all the contestants to gather and enjoy the day with others in their industry. We do indeed have a unique and outstanding group of people in the turfgrass industry, and this is one more opportunity to leave our workplaces and share ideas and friendship with one another. Thanks again to Fred Biggers and Wintergreen Resort for their part in making this event such a success for the past three years. An event of this magnitude requires a year of preparation, and the hours of volunteer work that go into this are colossal. The tournament benefits the research that is funded through the Virginia Turfgrass Foundation each year and represents our largest fundraising event. The Virginia Turfgrass Council, headed by a tournament committee, tackles this challenge. The VTF would like to say a personal thank you to each of the men and woman who serve on this committee. Their donation of time and effort does not go unnoticed, and we are so grateful to each of them: Tom Tracy, Brian Vincel, Frank Flannagan, Fred Biggers, Marc Petrus, Melissa Reynolds, Rick Owens, Rick Viancour, Scott Woodward, Steve Slominski, Steve Smith, Vince Henderson, Adam Nichols, David McCall, Erik Ervin, Jeff Derr, Mike Goatley, Rod Youngman, Sam Doak, Shawn Askew, Jeff Holliday, Jimmy Rodgers, John Pennypacker, Patrick Connelly, Gil Grattan, Randy Whelan and Sterling Caudle. Through these people, potential sponsors are contacted, and teams are “encouraged” to participate. We thank all of you who were a part of this year’s research tournament, with a special thank you to our sponsors. Without them, we would not benefit from the level of impact we have on quality turfgrass research in the state of Virginia. c

Congratulations to the Winners! Gross Score: Growth Enhancer Team (Lester Craig, Roscoe Craighead, Luke Craighead and Ben Fireball) Second Place: Salisbury Country Club Third Place: Tom Rash

Holding the Commonwealth Cup above, the GWGCSA team of Scott Furlong, Bo Jumbercotta, Mike King and Steve Slominski won the competition held among Regional Golf Course Superintendent Associations.

Gus Constantino Memorial Cup: Trinity Turf/SipcamAdvan (Layton Jarrels, Hunter Morrisette, Dwayne Watson and Kurt Hellenga) Second Place: Virginia Green Third Place: BASF

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Commonwealth Cup Greater Washington GCSA Closest to the Pin Mike Sigmon Dwayne Watson Terrance O’Neil Longest Drive Gordon Kretser Luke Craighead Tommy Baldwin Putting Contest Neil Jones

Thank You to Our Sponsors! Dinner Southern States Beverage Carts BASF Landscape Supply Precision Labs Lunch NuFarm Quali-Pro Eagle BASF FMC Smith Turf & Irrigation $20,000 Shoot-Out AGROTAIN Putting Contest Arysta LifeScience

Birdie Agrium Advanced Tech. Bayer Environmental Science Buy Sod, Inc. Coggin Agronomic Solutions East Coast Sod and Seed ENP Fertilizer Fisher and Son Co. G.L. Cornell Home Field Fertilizers Innovative Turf Services Landscape Supply McGill Environmental Solutions Salisbury Country Club Smith Turf & Irrigation Syngenta Tom Rash Company Trinity Turf/SipcamAdvan Virginia Green

Club Chantilly Turf Farms DuPont Prof. Products Goodyear Golf Club Greater Washington GCSA Growth Enhancer Luck Stone Revels Turf & Tractor Shenandoah Valley Turfgrass Assn. Troy Fink Virginia Tech Virginia Turfgrass Assn. Woodward Turf Farms Hole Davisson Golf Harco: The Harrington Co. Harmon Turf Services Helena Chemical Co.

Journal of the Virginia Turfgrass Council

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Cover Story

Weathering the

Storm

– Bermudagrass Winterkill 2010–11

By Mike Goatley Jr., Ph.D., Whitnee Askew and Erik Ervin, Ph.D., Virginia Tech

urfgrass scientists look at environmental extremes as blessings in disguise. As researchers, the Virginia Tech team is pleased when environmental extremes allow for some “separation” in turfgrass-variety performance. At the same time, we hate to see these challenges posed to our industry colleagues whose livelihood is managing these same grasses that might have perished during one of these extremely challenging periods. The winter of 2010–11 at the Turfgrass Research Center in Blacksburg provided some important new information in bermudagrass winter hardiness for our transition-zone climate.

What is winterkill?

One of the most pertinent descriptions of winterkill overheard in the past few years was when a fellow scientist from another land grant university said, “Winterkill is like pornography. You don’t know how to explain it, but you know what it is when you see it.” This no doubt leaves you scratching your head in how bermudagrass winterkill and pornography could ever be linked, but you get the point, don’t you?!

Contributing factors

The factors that somehow combine to create bermudagrass winterkill include the following.

Low temperatures

Although cold weather is the most obvious of the criteria, this is not always a clear-cut reason why winterkill occurs. Growth-chamber studies from Oklahoma State University reported that the lethal temperature for 50% of the bermudagrass stems tested ranged from 17°F for Midlawn to approximately 22°F for AZ Common. These studies exposed the stems directly to the low temperatures for specified time periods with no “insulating” effect of the soil (mineral, organic and moisture components) and any dormant foliage. Therefore, it is probable that bermudagrass stems can survive lower temperatures in the field due to the insulating value of the soil and the turf canopy.

Soil moisture

Either too wet or too dry is a likely contributor to winterkill. Wet soils require more energy to cool AND more energy to warm — they resist rapid changes in temperature, so

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this can both work for you and against you in terms of winterkill. Dry soils will have significantly greater variation in temperature, both highs and lows. Many people attempt to mediate winter damage by manipulating soil moisture, especially during a dry year when Mother Nature allows a turf manager some level of control. Desiccation (moisture evaporation from the plant’s leaves) is likely a very significant contributor to winterkill, and it is a factor that is often forgotten in the dead of winter, especially when most irrigation systems are “winterized” for the season.

Soil compaction/traffic

A compacted soil will likely already have restricted root growth and overall poor health entering the winter season. Compacted soils are often also poorly drained soils. Soil compaction should be addressed during the active growing season so that the turf can properly heal before winter dormancy.

Exposure

The weakest areas on an annual basis will be those with northeast

exposure. The steeper the slope, the greater the likelihood of damage.

Shade

Bermudagrass does poorly in the shade under ideal temperature and moisture conditions. Winterkill is often seen in direct correlation to tree-lined fairways or multi-tiered stadiums where the winter sun never strikes the field, usually in the southeast endzone.

Improper fall management

This is the “wild-card” category. Improper fertility, soil nutrient levels and pH, cultivation, mowing height, pest pressure (particularly a history of spring dead spot), pesticide applications… they all can contribute to winterkill. Out of this group, the most likely suspect is an excessively low mowing height leading into the fall dormancy period. These turfs have shallow roots systems, less foliage to modify soil surface temperatures and lower stored carbohydrates (i.e., food) in their stems.

Patriot

Midlawn

Tifway

OKC 1134 (Northbridge)

Poor growing season/ first-season establishments

Cool, cloudy summers are great for our air-conditioning bills but not conducive to bermudagrass growth. The likelihood of winterkill is always increased after coolerthan-normal summers. First-season establishments are also much more susceptible to winterkill. Seeded bermudagrass stands have very limited rhizome and stolon production during the first year in particular. Establish bermudagrasses as early in their growing season as possible to enhance their first winter-survival potential.

Photo 1. Winterkill damage on vegetative bermudagrass varieties (photo taken on 5/20/2001).

NuMex Sahara

Princess 77

Riviera

Yukon

The winter of 2010–11

Several other factors could be as important as those detailed above, but those cover the most likely causes of damage on a regular basis in Virginia. As mentioned previously, the winter of 2010–11 provided VT researchers some

Photo 2. Winterkill damage on seeded bermudagrass varieties (photo taken on 5/20/2001).

Journal of the Virginia Turfgrass Council

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Cover Story continued

Table 1. Spring greenup (%) and visual quality ratings (1 = poor, 9 = excellent) for the 2007 National Turfgrass Evaluation Program Bermudagrass Trial in 2009-10 and 2010-11.

(1 -9 ) Q

ua lit y

re e

p nu

ua lit y

re e

5/20/11 5/20/11

5/2/11

(1 -9 )

6/9/10

nu re e G %

re e

4/20/10 6/9/10

Midlawn

Vegetative

100

Yukon

Seeded

100

OKC 1134 (Northbridge)

Vegetative

100

Bar 7CD5

Seeded

100

RAD-CD1

Seeded

100

PSG9Y20K

Seeded

100

Patriot

Vegetative

100

Riviera

Seeded

100

PSG PROK

Seeded

Premier

Vegetative

100

OKS 2004-2

Seeded

100

Hollywood (J-720)

Seeded

100

OKC 1119 (Latitude 36)

Vegetative

100

Pyramid 2 (IS-CD10)

Seeded

SWI-1122

Seeded

Tifway

Vegetative

Veracruz

Seeded

SWI-1081

Seeded

PSG 9BAN

Seeded

SWI-1070

Seeded

SWI-1117

Seeded

SWI-1083

Seeded

Gold Glove

Seeded

SWI-1057

Seeded

Sunsport

Seeded

PSG 94524

Seeded

Princess 77

Seeded

SWI-1113

Seeded

IS-01-201

Seeded

PSG 91215

Seeded

NuMex-Sahara

Seeded

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Cover Story continued

pretty clear data on winterkill potential at our Blacksburg location on the 2007 National Turfgrass Evaluation Program bermudagrass trial. While turf loss across the state was not catastrophic last winter, many bermudagrass managers reported quite a bit of damage on some of our “less cold-hardy” varieties following what seemed like a less severe winter than 2009–2010. And, based on low temperatures, the winter of 2010-11 was not as severe as 2009–10. The one factor that was quite different between the two years, however, was snow cover. Turfgrass program manager Whitnee Askew compiled low-temperature data and snow cover from December through February of each year (Figure 1), and what is obvious is that we most often had very significant snow cover during the most extreme low-temperature events of 2009–10, a very snowy season. Many of you will remember how extreme snow mold showed up on both cool-season and warm-season turfs during the spring of 2010, one of the negative aspects of the persistent snow cover. For 2010–11, the low temperatures were not nearly as extreme, but they often were not accompanied by snow cover and its exceptional insulating capability. The spring greenup data and visual turf quality ratings (Table 1) between the two years emphasize the extreme differences in winter hardiness of the cultivars. While seeded bermudagrasses generally had the least winter hardiness, there were some important exceptions, as noted by two of our standard recommendations in this state, Yukon and Riviera, the newly named variety ‘Hollywood’ and some exciting experimentals (Bar7CD5, RAD-CD1 and PSG9Y2OK). In the vegetative category, the top performers in 2010– 11 in winter hardiness were longtime testing standard Midlawn, the recently named Northbridge (OKC 1134) and Patriot. Photos 1 and 2 display the varying degrees of winter hardiness between standard and newly named varieties.

and preventing winterkill, as there has been sporadic damage to even our most cold-hardy bermudagrasses over the years. Adjusting bermudagrass management programs to better prepare the grass for winter survival is important anywhere in the state. However, a winter like 2010–11 provides some clear distinctions in the winter-hardiness variability in bermu-

dagrass varieties that should help turfgrass managers in Virginia make more informed choices in grass selection. The “survivors” offer highly variable colors, densities, leaf textures and growth rates that should also be part of the selection criteria. We invite everyone to see the plots firsthand at the 2011 Virginia Turfgrass Field Days in Blacksburg on August 31. c

Conclusion

Unfortunately, there really never is a true conclusion to defining, predicting

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Applied Research

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Soil Texture, Wetting Agents and Water-Repellent,

SAND-BASED SPORTS FIELDS By Tom Samples, Ph.D., and

uring sports-field construction, sand is often added to, or used to cap, the existing native soil to create or “manufacture” a coarse-textured turfgrass rootzone that is resistant to compaction. When an appropriate amount of sand is mixed with soil, the soil becomes coarser, and the size of air (pore) spaces among soil particles increases, allowing water to drain much faster. The texture of a soil is a measure of its fineness or coarseness. Sand particles are relatively large, or coarse, ranging from 0.05 to 2.0 millimeters (mm) in diameter (Table 1). Silt particles, which range from 0.002 to 0.05 mm in diameter, are intermediate in size, compared to sand and clay particles. Clay particles are very small, or fine, with a diameter less than 0.002 mm. The amount of sand, silt and clay in a soil influences how much of the total pore space will hold water against gravity (capillary) and how much will not (non-capillary). Much of the water in soil is held as a film on the surface of clay particles, which is one reason that soils high in clay retain more water against the pull of gravity than sandy soils (a high-clay soil may have nearly a million times more surface area than a very-coarse-textured, sandy soil). Since the surface of clay and organic matter is negatively charged,

John Sorochan, Ph.D., The

these two soil components account for the majority of a soils’ nutrientholding capacity. Because sand particles are large and have very little surface area, sand serves as a structural framework and contributes very little to the chemical reactions that take place in a soil. A very large amount of sand is needed to exert as much influence on soil properties as a comparatively small amount of clay. Sports-field soils that resist compaction and have many large air-filled pores often contain at least 70 percent sand by volume.

Soil mechanical analysis

Sports-turf professionals who manage turf in sandy soils are very familiar with soil and tissue testing for nutrient analysis. A soil sample can also be submitted to a soil physical testing laboratory for mechanical or particle-size analysis to determine texture. A full mechanical analysis involves extracting all silt and clay particles from the soil sample before sieving the resulting sand fraction. Because sands vary in coarseness, a particle-size analysis is especially helpful when determining how much of a particular sand to add to a native or existing soil for best field performance. In the U.S., soils are grouped (according to the proportion of sand, silt and clay) as clay, sandy

University of Tennessee

clay, silty clay, sandy clay loam, clay loam, silty clay loam, loamy sand, sandy loam, loam, silt loam, sand or silt. The texture of a soil also influences its bulk density, or weight in grams (g) per cubic centimeter (cm3) of oven-dry soil. Clay usually has a lower bulk density than sand.

Key Points at a Glance • Over time, sandy sports-field soils may become water repellent, or hydrophobic, near the surface, especially within the top 2". • Managing water-repellent soils often focuses on both the removal and chemical “alteration” of soil organic matter through core aerification and core removal, dethatching, topdressing and wetting agents. • Sometimes referred to as surfactants or soil penetrants, wetting agents may help prevent or reduce water repellency in sandy sportsturf soils. • Nonionic wetting agents usually persist much longer in soils than either anionic or cationic types, and they are the most common type used in formulations.

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Applied Research continued

Similarly, soils high in organic matter usually have a much lower bulk density than soils containing very little organic matter. The same sample used to determine bulk density can be used to calculate the total pore space of a soil, a very important physical characteristic. A known amount of oven-dry soil is placed in a pan of water until completely saturated. The saturated soil is then weighed. The difference in weight between the oven-dry sample and the saturated sample represents a volume of water equal to that of the total pore space. For example, a 180 cm3 soil sample containing 90 g (cm3) of water at saturation would have a total pore space of 50 percent. Soils high in silt and clay usually have a larger percentage of capillary pore space and are slow to wet, compared to sandy soils.

Water repellency

In time, sandy sports-field soils may become water repellent near the surface, especially within the top two inches. There are several sources of water repellency, or hydrophobicity, in soils. Turfgrasses produce waxy compounds on leaf surfaces that

can be dislodged by rainfall and irrigation. For example, the leaf cuticle (a very thin, waxy layer on the outermost portion of leaves) serves as a shield against penetration by insects and fungi and helps turfgrasses conserve internal moisture. However, once dislodged, waxes from the cuticle may collect in soil pores, restricting the rate at which water moves into (infiltration) and through (percolation) the soil. As clippings and roots decompose, organic films may coat sand particles and restrict water infiltration and percolation. Thatch contains large quantities of organic matter that can also become hydrophobic. Unique compounds called hydrophobins produced by algae can cause a soil to repel water. Hydrophobins may also develop along the advancing tip of fungi strands (hyphae) as they move through the soil. Several species of fungi, including the basidiomycetes that cause fairy ring, have been linked to hydrophobicity in sandy soil. The activity of nematodes and protozoa may also increase water repellency in sandy soils. In addition, water-repellent compounds such as

a Table 1. Characteristics of sand, silt and clay.

a b

sorgoleone are produced by turfgrass roots and can be adsorbed by soil particles, causing them to repel water.

Measurement

One of the simplest methods of determining if a soil is water repellent is to apply a volume of water to the surface of air-dry soil and record the amount of time from surface contact until the water penetrates the soil. When studying hydrophobic soils, researchers may perform a timed water-droplet penetration test (WDPT) or a more rapid, molarity of ethanol test (MED) using drops of ethanol rather than water. In both tests, the longer an individual droplet remains on the soil surface, the greater the level of water repellency. Recorded water droplet penetration times have ranged from less than one second to 10,000 or more seconds. One scale used by the Golf Course Superintendents Association of America to compare hydrophobicity in soils based on the WDPT is: 0 to 5 seconds = no repellency; 5 to 60 seconds = slight repellency; 60 to 600 seconds = moderate to severe repellency; 600 to 3,600 seconds = severe repellency; and more than 3,600 seconds = extreme repellency.

Negative effects

Particle Number (per gram soil)

Particle Surface Area

Particle Type

Diameter (mm)

Very Coarse Sand

1.0 to 2.0

Coarse Sand

0.5 to 1.0

720

Medium Sand

0.25 to 0.5

5,7000

Fine Sand

0.15 to 0.25

46,000

Very Fine Sand

0.05 to 0.15

722,000

227

Silt

0.002 to 0.05

5,776,000

454

Clay

< 0.002

90,260,853,000

8,000,000b

(cm2 per gram)

From: Foth and Turk, 1972. The calculated surface area of montmorillonite clay particles.

20 | VIRGINIA TURFGRASS JOURNAL July/August 2011 www.vaturf.org

Much of the rainfall and irrigation water received by turfgrasses growing in hydrophobic soils may puddle on the field surface or run off. The development of water repellency is a precursor to a condition known as localized dry spots. The moisture content within the turfgrass rootzone in a hydrophobic soil is usually variable, with extremely dry areas of soil interspersed with moist areas that often resemble fingers. Turfgrasses growing in these dry zones are most often poorly rooted and drought prone. Irregular soil wetting can also lead to the preferential flow of water and an uneven distribution of nutrients and pesticides within the turfgrass rootzone.

Applied Research continued

Prevention/management of water-repellent soils

Table 2. The effect of tine diameter and spacing on the amount of surface area affected by core aerificationa.

Since water repellency in sand-based athletic-field soils is due to the presence of organic compounds with hydrophobic properties, the management of water-repellent soils often focuses on both the removal and chemical “alteration” of soil organic matter.

Core aerification and core removal

Coring (core aerification) not only penetrates thatch and helps relieve soil compaction, but also it dislodges and lifts organic matter along with the aeration cores. As cores are harvested, some of this organic matter is physically removed from the upper portion of the turfgrass rootzone. The amount of turf surface affected and the amount of soil and organic matter removed during each aerification depends on the tine diameter, length and spacing (Table 2). The benefits of core aeration for the removal of soil organic matter are often short-lived. Researchers at Michigan State University found that core aerification at a five-percent-surface-area impact applied twice a year on a ‘Penneagle’ creeping bentgrass putting green with a loamy-sand soil did not permanently reduce the total organicmatter content of the soil. Similarly, research conducted on a bermudagrass putting green growing in a loamy-finesand soil demonstrated that the total organic-matter content was reduced only when core aerification was increased from twice in seven months to once each month for seven months.

Tine Diameter (inches)

Spacing (inches)

Number of Holes/sq. ft.

Surface Area Contact (percent)

1/4"

1" x 1"

144

4.9%

1/4"

1" x 2"

2.5%

1/4"

2" x 2"

1.2%

3/8"

1" x 1"

144

11.0%

3/8"

1" x 2"

5.5%

3/8"

2" x 2"

2.8%

1/2"

1" x 1"

144

19.6%

1/2"

1" x 2"

9.8%

1/2"

2" x 2"

4.9%

5/8"

1" x 1"

144

30.7%

5/8"

1" x 2"

15.3%

5/8"

2" x 2"

7.7%

From: Hartwiger and O’Brien, 2001.

Dethatching and thatch removal

A vertical mower can be used in a variety of ways, depending on the depth setting and blade width of the vertical knives (Table 3). Grain is reduced in turfs when the vertical mower is adjusted so that the knives cut stolons and tillers but barely strike the soil surface. Immediately after core aerification, a vertical mower can be used to break up the aeration cores and re-incorporate soil. Journal of the Virginia Turfgrass Council

| 21

Applied Research continued

Table 3. The effect of blade width and spacing on the amount of surface area affected by dethatchinga. Dethatching Blade Width (inches)

Spacing (inches)

Surface Area Contact (percent)

9/64"

1" x 1"

14.1%

9/64"

1" x 2"

7.0%

5/64"

1" x 1"

7.8%

5/64"

1" x 2"

3.9%

From: Hartwiger and Oâ&#x20AC;&#x2122;Brien, 2001.

When the dethatching knives are set to penetrate into the soil, thatch is lifted and the soil is cultivated. Recently, deep-vertical mowers have been manufactured with thatch removal, soil cultivation and turf renovation in mind. Seed can be broadcast after deep-vertical mowing to introduce a new species or variety into the existing sports turf.

Topdressing

After dethatching, topdressing with sand and then dragging (matting) the turf mixes sand particles with thatch. This modification of the thatch layer results in the formation of mat, a tightly intermingled layer of sand particles and living and partially decomposed turfgrass stems and roots. Water usually moves more quickly into a mat layer than into an excessive layer of dry thatch. Both thatch and mat layers may retain more water after being treated with a wetting agent.

Wetting agents

Wetting agents were invented in the mid-1950s. Sometimes referred to as surfactants or soil penetrants, wetting agents may help prevent or reduce water repellency in sandy sports-turf soils. A wetting agent may be capable of reducing the surface tension and improving the wettability of an individual liquid,

22 | VIRGINIA TURFGRASS JOURNAL July/August 2011 www.vaturf.org

such as water. A wetting agent may also lower the surface tension between two liquids, a liquid and a gas, or a liquid and a solid. Wetting agents are produced from fats and oils (or oleochemicals) and petrochemicals produced from petroleum. The result is a synthetic, complex organic compound with both hydrophobic and hydrophilic parts. When applied to turf, the hydrophobic part of a wetting agent sticks to water-repellent compounds and surfaces, while the hydrophillic part sticks to water. Wetting agents are anionic, cationic and nonionic. Anionic wetting agents are negatively charged, are easily leached and usually have a short residual â&#x20AC;&#x153;lifeâ&#x20AC;? in soils. Like soaps, which are water-soluble sodium or potassium salts of fatty acids, anionic wetting agents can be very toxic to plants (phytotoxic). Because cationic wetting agents are positively charged, they are tightly held by negatively charged soil particles and organic matter. Cationic wetting agents also tend to be phytotoxic, and they wet slowly. Nonionic wetting agents have neither a positive or negative charge. They usually persist much longer in soils than either anionic or cationic types, and they are the most common type used in formulations. Today, more than 70 products are marketed for use in the green industry and in agriculture. Wettingagent formulations vary in their effectiveness in reducing water repellency in sandy soils and their improvement of the evenness of soil wetting. Wetting-agent applications may be much less beneficial when weather is rainy. Since they are broken down by soil microorganisms, wetting agents must be applied several times during the turfgrass growing season. For more precise information about the mode of action and recommended application timing and rate of a specific wetting agent, please consult your product technical representative and refer to the product label. c

Turf Talk

By Stanley J. Zontek, Director, Mid-Atlantic Region, USGA Green Section

Editor’s Note: This article was originally published in the May/June 1988 issue (Vol 26(3): 1-4) of the USGA Green Section Record. 22 years later, the author’s recommendations remain as accurate today as they were then. This article has been updated by the author, with permission to republish it in the Virginia Turfgrass Journal.

mong the responsibilities of today’s golf course superintendent, the need to maintain a good stand of grass on putting greens is perhaps the most basic of all. Greens are the bread and butter of a golf course, and the reputations of a course and the superintendent who maintains it are often determined by the consistency of those greens. As long as the greens look good and putt well, golfers are inclined to overlook other weaknesses on the course. If this consistency fails for even a short time, though, the superintendent will be criticized — and golfers can be merciless in their criticism of even the least significant flaw. Maintaining good putting green turf for most of the season is not as difficult as it once was. Science has given us a better understanding of how to maintain closely cut, heavily trafficked turf, and well-timed practices such as aeration, topdressing, fertilization, overseeding and other renovation work can prepare the turf and the soil for the next period of stress. However, when encountering stress in mid-season, putting green management often takes on a meaning all its own: doing what is necessary to keep the grass alive under stress conditions.

Types of turf stress

Turfgrass stress can be defined in a number of different ways. By the book, stress is the “strain or pressure causing a departure from the normal equilibrium.” For the turf manager in the field, stress is what causes the grass to wilt and die right before his eyes. The turf on greens is exposed to many elements that can cause stress. The turf manager has little or no control over some of these factors, such as the amount of play a course receives or under what weather conditions this play occurs. Other stress factors are imposed by the superintendent himself, including extremely close mowing,

the abrasion caused by turning heavy triplex mowers on the green perimeters and collars, deep vertical mowing, too much or too little irrigation and misapplying certain chemicals. These stresses can be broadly grouped under mechanical stress. The other category of stress the turf manager must deal with is given the name environmental stress. Temperature or humidity that is either too high or too low, rainfall that is either too much or too little and/or the presence of frost are examples of environmental stress. Generally speaking, any of these environmental or mechanical stress factors will not cause the loss of grass by themselves, but when a combination of stresses occurs at the same time (e.g., close mowing when the turf is under stress), the turf can be severely weakened and may die. When this occurs on greens, it means an immediate public relations problem between the golf course superintendent and those who play the course. Following is a listing of some of the management factors that the golf course superintendent can control to some degree as he manages his turf under conditions of stress. Some may seem obvious, while others are less so, but all of them are worth considering in managing periods of heavy play and the accompanying stresses. After all, loss of turf on greens is something that all golf course superintendents and golfers want to avoid.

Tips for managing mechanical stress Raise the mowing height.

Mowing the grass too close when under stress is a common cause of turfgrass failure. In many cases, the golf course superintendent feels pressured into sustaining low cutting heights for the sake of fast greens, resulting in thin, weak or dead turf and a mob of angry golfers.

Journal of the Virginia Turfgrass Council

| 25

What should be done? When the grass is under severe stress and is being cut too low, and where thinning and scalping damage is seen, raise the mowing height as quickly as possible. Even a slight 1/64" to 1/32" increase in cutting height can have a very beneficial effect. In contrast, lowering the cutting height by this small increment to increase green speed can have a disastrous effect. The old saying â&#x20AC;&#x153;slow grass is better than no grassâ&#x20AC;? is so very true.

Skip mowing.

The physical act of cutting grass with a heavy machine is itself a significant stress. Common sense would suggest that when the grass is under extreme stress (and its rate of growth slows), skip a few days of mowing each week. The greens may lose a little speed, but again, slow grass is better than no grass. Also, consider alternating rolling with mowing. Research has shown this to be a good technique to reduce stress while still maintaining green speed and trueness of ball roll.

Avoid double-cutting greens.

While double-cutting is one of the most useful techniques at the disposal of the golf course superintendent to achieve and maintain fast greens, it is, nevertheless, another form of mechanical stress. Therefore, when the grass is suffering from stress, defer doublecutting until conditions moderate.

Use walk-behind mowers.

Walk-behind units place less mechanical stress on the turf than triplex mowers. While it is true that triplex mowers are marvelously efficient machines, they do cause extra stress on the turf, especially on the clean-up cut around the greens. This mechanical wear is one of the most compelling reasons why more and more golf courses are going back to walk-behind mowers during periods of stress. The pleasing, traditional striping effect it causes is an added advantage of hand mowing. Finally, many superintendents feel that walk-behind units do a consistently better job of cutting, while minimizing wear stress at the same time.

26 | VIRGINIA TURFGRASS JOURNAL July/August 2011 www.vaturf.org

Turf Talk continued

Watch out for grooved rollers.

The Wiehle roller is an excellent grooming device for creating better putting green texture and quality, compared to mowers with other types of rollers. When the grass is tender and under stress, however, the extra abrasion these rollers cause, especially on the perimeter cut, can be a major source of stress. Thus, use grooved rollers religiously when mowing the grass during nonstress times, but consider replacing them with solid rollers when the turf is under stress.

Skip the “clean-up” lap.

When the turf is under stress and top growth is minimal, consider performing a “clean-up” lap on an as-needed basis. Also, defer routine maintenance operations like topdressing and vertical mowing of greens when turf is under stress. In short, do whatever is necessary to minimize mechanical stress on greens when they are under prolonged stress. Putting green speed and quality may be sacrificed slightly during this time, but it is a small price to pay for avoiding the loss of turf and the turmoil that would accompany such a loss.

Managing environmental stress

Heat, moisture, disease and nutrient stresses are key problems in maintaining healthy turf during the golfing season. Good management techniques can minimize these stresses, although the chemicals and materials used to prevent injury sometimes cause stresses of their own. Following is a checklist of management factors to consider for handling various environmental stresses.

Syringe the greens

Syringe the turf occasionally to reduce heat and moisture stress. Applying the correct amount of water is the key to this program. Syringing is often overdone, causing saturated turf and disease. Syringing is best done by hand, using trained workers with some good judgment, and applying water only to those sections of the greens that require it. Hand syringing is time consuming, but it is necessary, given the demands of golfers today.

Increase airflow.

Open up pocketed greens (those partly enclosed by a dense stand of trees and underbrush). Stress problems

Journal of the Virginia Turfgrass Council

| 27

Turf Talk continued

are always more severe on pocketed greens. It is always hotter and more humid in these pocketed areas, and the grass is always weaker because of it. Air circulation can be improved by thinning out the extraneous trees and underbrush near the green and by pruning up the lower branches of the remaining specimens. Without a doubt, good air circulation is critical in allowing the turf to transpire and cool itself by releasing moisture through its stomata. Providing good air circulation is also helpful in drying the green to minimize disease and algae problems. Therefore, anything that can be done to improve airflow in the vicinity of golf greens should receive high priority.

Control diseases.

Many turf diseases become active when the turf is under stress. Controlling disease during the season is particularly important, as turf lost from disease activity at this time of year will be slow to recover. To prevent this from occurring, compress your preventive fungicide spray schedule (if necessary), be sure to make an accurate diagnosis of the disease if symptoms are observed, and use curative rates of the most effective yet least phytotoxic fungicide labeled to control that disease. Also, be sure to alternate materials or tank-mix contact and systemic fungicides (when appropriate) for broad-spectrum disease control and to reduce the potential for fungal resistance problems.

Think twice before making applications.

Do not apply pesticides, fertilizers or combinations of products that have the potential to burn the turf. Grasses under heavy stress often react negatively to what are usually considered mild herbicides or moderate rates of certain types of fertilizers. If in doubt, defer treatments to when the turf can tolerate the applications better. If crabgrass or other weeds must be treated, consider hand picking rather than using herbicides. Though time consuming, it may be better than dealing with burned grass. Misapplications can be especially devastating during stressful weather. Applying the wrong rates or allowing overlapping (which essentially doubles the intended rate) is a common cause of turf injury during hot weather. If you’re not confident about important applications, consider using foam markers or application dyes for spray applications, or switch to granular formulations and drop spreaders, if necessary. If fertilization is deemed necessary, keep rates in the light to ultra-light spoon-feeding range. Soluble fertilizer sources containing N-P-K plus micronutrients seem to work well at rates as low as 1/16 lb. or as high as 1/4 lb. of actual nitrogen per 1,000 square feet per application. Non-burning, low-nitrogen-content natural

organic fertilizers can also be used to good advantage, but keep the rates low, in the range of 1/8 to 1/4 lb. of nitrogen per 1,000 square feet. Keep in mind that more fertilizer can always be added, if needed. If excess fertilizer has been applied, though, nothing can be done but live with the consequences.

Aerate the turf.

If the greens begin to thin and you feel they are in trouble, consider aerating the turf. That’s right, aerate. Although it may seem inconsistent to aerify while, at the same time, trying to avoid turf stress, there is usually more to gain than to lose. Aeration helps a soft, wet soil dry out, and it allows oxygen back into the rootzone where it is so badly needed. It also improves water infiltration into tight, compacted soils and relieves the effects of isolated dry spots. Very often, the turf begins to improve within a few days after aerification. As a precaution, use small tines, and do not let the greens dry out too much. Small solid-tine aerification, water aerification (Hydroject) or deep spiking may also be of help in this situation.

Explain what you’re doing.

Finally, communicate with the people at your course. Discuss the situation with the green committee chair, president, golf professional, course administrator, general manager or anyone else who has a need to know. Begin the conversation by saying something like, “Gentlemen, we will have a problem if things continue as they are…” That should get their attention. No one likes a surprise, especially finding dead greens that only a few days before were fully turfed and in beautiful condition. Tell them the story in clear, concise terms. People tend to be understanding if they know the facts. After all, no matter how good a job a golf course superintendent does, he cannot control the weather. Without a doubt, weather extremes remain the number one stress factor on golf courses today.

When the weather breaks…

When the period of stress is over, assess the condition of your golf course. Count your losses, and analyze what you think caused the problems your course experienced. After all, there is nothing like a prolonged period of stress to bring out whatever strengths and weaknesses exist on the course. You may determine that the greens need more and deeper aeration, that a better irrigation system needs to be installed or that trees need to be removed from around pocketed greens. Also, use the experience in a positive way to determine which practices need to be altered and which programs should be implemented to manage turf better when it is under stress. c

28 | VIRGINIA TURFGRASS JOURNAL July/August 2011 www.vaturf.org

Index of Advertisers

Calendar of Events

Turf Industry Events August 30–31

December 14–16

October 27–29

January 11–13, 2012

Turfgrass Field Days Blacksburg, VA

Green Industry & Equipment Expo Kentucky Exposition Center Louisville, KY

December 12–14

Turfgrass Short Course Charlottesville, VA

Turfgrass Short Course Virginia Beach, VA

Mid-Atlantic Nursery Trade Show Baltimore Convention Center Baltimore, MD

January 10–14, 2012 STMA Annual Conference & Exhibition Long Beach Convention Center Long Beach, CA

January 16–19, 2012 VTC 52nd Annual Turf & Landscape Conference and Trade Show Fredericksburg Expo & Conference Center Fredericksburg, VA

January 19, 2012

Pesticide Recertification Fredericksburg, VA

February 2012

Pesticide Recertification Turfgrass and Virginia’s Waters Virginia Beach, VA

Bayer................ Inside Front Cover www.bayerprocentral.com Buy Sod...................................... 9 www.buysod.com Camp Chemical Corp.............. 22 Collins Wharf Sod Farm.......... 17 www.collinswharfsod.com E & S Soil and Peat.................. 30 www.eandssoil.com East Coast Sod & Seed............ 23 www.eastcoastsod.com Egypt Farms, Inc.......................... 26 www.egyptfarms.com Fisher & Son Company, Inc........ 13 www.fisherandson.com FMC Professional Solutions........ 5 ww.fmcprosolutions.com w Kesmac/Brouwer, Inc................... 3 www.kesmac.com Landscape Supply, Inc........... 29 www.landscapesupplyva.com Luck Stone Specialty Products.................. 17 www.luckstone.com Mid Atlantic Sports Turf......... 26 Modern Turf, Inc..................... 21 www.modernturf.com Oakwood Sod Farm, Inc......... 11 www.oakwoodsod.com Quali-Pro.......... Inside Back Cover www.quali-pro.com Roxbury Farm & Garden Center.............................. 9 www.roxburyfarmgarden.com Southern States Cooperative.... 27 www.southernstates.com The Turfgrass Group...................... 7, Back Cover www.theturfgrassgroup.com Winfield Solutions, LLC............... 11 Wood Bay Turf Technologies.... 29 www.woodbayturftech.com Woodward Turf Farm, Inc........... 8 www.woodwardturf.com

Virginia Turfgrass Council (VTC) 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, Virginia Turfgrass Journal, or its editors. Likewise, the appearance of advertisers, or VTC members, does not constitute an endorsement of the products or services featured in this, past or subsequent issues of this bimonthly publication. Copyright ©2011 by the Virginia Turfgrass Council. Virginia Turfgrass Journal is published bimonthly. Subscriptions are complimentary to members of VTC. POSTMASTER: Send change of address notification to VTC, P.O. Box 5989, Virginia Beach, VA 23471. Postage guaranteed. Third-class postage is paid at Nashville, TN. Printed in the U.S.A. Reprints and Submissions: Virginia Turfgrass Journal allows reprinting of material published here. Permission requests should be directed to VTC. 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 37068-0142, (615) 790-3718, Fax (615) 794-4524. Deadlines are the first of the month prior to the following month’s publication. (Example: August 1 for the September issue.)