Alabama Turf Times - Spring 2021

Spring 2021

New Herbicides for 2021 Take-all Root Rot A Detrimental Root Disease of Bermudagrass Putting Greens

UPGRADE TO FIRST CLASS 38% Less Water Greater Fall Color Retention

Earlier Spring Transition Increased Wear Tolerance

Reduced Fertility Requirement Extremely Rapid Grow-In

www.TheTurfgrassGroup.com

Spring 2021

TOP FEATURES 12

Recent Events — 10 Virtual Road Shows

Sponsor Appreciation

14

Cover Story —

New Herbicides for 2021

Feature Article — 18 Take-all Root Rot:

A Detrimental Root Disease of Bermudagrass Putting Greens

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ATA Member Spotlight —

Mickey Pitts

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DEPARTMENTS

Al ab ama Tu rf Tim es > >> Spring 2021

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From the President’s Pen

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ATA Annual Sponsors

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Industry News

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Calendar of Events

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Index of Advertisers

Find this issue, Podcasts, Events and More: THETURFZONE.COM

The Alabama 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, Alabama Turf Times, or its editors. Likewise, the appearance of advertisers, or their identification as Alabama 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 © 2021 by the Alabama Turfgrass Association. Alabama Turf Times is published quarterly. Subscriptions are complimentary to members of the Alabama Turfgrass Association. Third-class postage is paid at Jefferson City, MO. Printed in the U.S.A. We are not responsible for unsolicited freelance manuscripts and photographs. Contact the managing editor for contribution information. Advertising: For display

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From the President’s Pen >>>

A SURGE OF

Al ab ama Tu rf Tim es > >> Spring 2021

As

HOPE

we navigate these unprecedented days and times in our lives, we become aware of how nice stability is! So much has changed and been altered in our everyday routines that we’ve become somewhat accustomed to the continual adjustments. With promising news in recent weeks regarding distribution of a vaccine, and with the ending of a calendar year many of us would never like to repeat, we feel a surge of hope. Now is the time to bear down and see these last (hopefully) few months through to a point where we can see golf courses full of players, athletic fields overflowing with kids, supply houses and shops stocked to the roofs, full trucks rolling out of sod farms, and homeowners excited to enhance or improve their lawns and gardens. We can get there, and it won’t come too soon.

Our association has made adjustments to continue to offer a strong slate of events for education and learning. The Road Shows were, of necessity, virtual this year with the usual strong slate of speakers and topics chosen specifically to offer the latest information. Two dates were planned to allow flexibility for members to attend and earn pesticide points. Your ATA Board continues to meet to work out event details for the benefit of our membership. We have the Lawn and Landscape workshop planned later this spring in Gardendale, Alabama, and the Auburn University Turfgrass Unit Field Day, and the Poa annua event are both tentatively scheduled for July. Look for those dates to be announced.

I want to congratulate the incoming 2021 ATA Board members that have recently begun their service to our industry. A huge, special thanks to the members who have extended their Board service and have graciously agreed to take on expanded roles.

Without the commitment of our Board members and the dedication and effort they put into improving our Association we would go nowhere. Our newest Board members were highlighted in the last issue of Alabama Turf Times and are a high quality, diverse cross section of our constituency who will help lead the ATA for years to come. If any members are interested in serving the ATA in a Board role, helping with an event, or have interest in hosting an event, please let us know. Take advantage of the opportunity to help forge the future of the ATA and get involved. We all know people who have connections with the green industry, but are not members, or think membership is something they can do without. I challenge all of us to pitch the ATA again, to explain that the ATA is what we make it, and there is something to gain from involvement.

This edition of the Turf Times is once again chock full of important and timely information. Dr. Scott McElroy discusses the latest research and findings on herbicide use, specifically a new herbicide combination of familiar trade names, a new active ingredient product and a new version of an old standby product. No matter what changes we are forced to undergo, there remains a constant struggle for effective weed control. As you read this information there are diabolical environmental adaptations these plants are undergoing to overcome our best efforts to put them in their place.

Dr. McElroy's piece will help us work through these issues. Dr. Maria Tomaso-Peterson contributes with information concerning Take-All Disease, another issue most of us will confront or are confronting. When these articles initiate questions or thoughts as you read them through, you can plan to attend one or all of our scheduled events to seek counsel with other members, professional product representatives, or even the authors themselves. The ATA is working for you!

Longtime member Mickey Pitts is our member Spotlight in this issue. Mickey served on the Board for several years, two of which were on the Executive Board. Check out the article to see what Mickey is doing these days.

Moving into the warming months ahead, through the season of renewal, the ATA and Board wish all the members a spectacular spring. We hope to see and visit with you through the year at our events and gatherings.

Joe Collins, CSFM 2021 ATA President 6

Joe Collins, CSFM

2021 ATA ANNUAL SPONSORS GOLD • Bayer Environmental Science • Beard Equipment Company • Greenville Turf & Tractor • Harrell's, Inc. • Jerry Pate Turf & Irrigation • Simplot, Inc.

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BRONZE • Agromax • Aquatrols • BASF • GreenPoint Pro • PBI-Gordon • Southern States Turf • Sur-Line Turf • Walker/Wright Mowers

Alabama Turf Times is the official publication of the: Alabama Turfgrass Association P.O. Box 70 Auburn, Alabama 36831 Tel: (334) 821-3000 Fax: (334) 821-3800 Email: mailbox@alaturfgrass.org www.alaturfgrass.org

PROVIDING THE BEST SELECTION OF TURF AND LANDSCAPE PRODUCTS, COMPETITIVE PRICES, AND EXCELLENT CUSTOMER SERVICE.

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Vice President Ben Anderson

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Past President Deven Peek

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BOARD OF DIRECTORS Golf Patrick Pierce

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EX OFFICIO/EDUCATION ADVISORS David Han, Ph.D. Auburn University (334) 844-3980 handavi@auburn.edu

Jim Jacobi, Ph.D.

Alabama Cooperative Extension System (205) 879-6964, Ext. 19 jacobjc@auburn.edu

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Industry News >>>

A Message from ATA Vice President Ben Anderson about a

PROPOSED NEW PESTICIDE PERMIT CATEGORY

H

appy New Year! I hope that everyone is making the best of their 2021 so far. The article on the next page is from Ron Wright CGCS, the Southeast field staff representative for the Golf Course Superintendents Association of America. Many of you may not know Ron since he focuses on golf, but he also speaks on behalf of all turf industries, when he considers upcoming hurdles the industry will face. This letter is an important read, and I encourage everyone to take the time to carefully consider the information he is sharing. I shared my PowerPoint presentation with the ATA Board of Directors prior to the Green Industry stakeholders meeting with the Alabama Department of Agriculture and Industries in order to obtain input from their wide turf backgrounds.

My guess is, we will all be affected one way or another by this new regulation.

There is some good news! The State is allowing us to share our suggestions on this issue. Both Ron and I

gathered information and put together PowerPoints to be able to make suggestions on how we think this new regulation should function. I shared mine with the rest of the ATA Board of Directors, that have all different turf backgrounds, to have all the input possible. Ron had the input of the Alabama Golf Course Superintendents Association Board of Directors after they reviewed his PowerPoint as well.

I feel like both associations will do their best to speak for the industry and make these changes as easy as possible.

We presented these PowerPoints on January 28th and have input on the structure of the new rules that Ron describes on page 9.

Thanks,

Ben Anderson ATA Vice President

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2021

staff that already has a license with the state to apply plant protectants, you really don’t have to change anything with your company. But if you have any staff that does not possess a state spray license, they will need to obtain the new license or stop applying the products and turn those duties over to a crewmember who does have a license.

There is still much to be determined about this program as far as costs, testing, record keeping and training availability.

Most states are trying to figure all those issues out right now.

The EPA wants all 50 states to submit a plan to them by March 4, 2021. That is only weeks away. We will keep our members updated on the outcomes and what we need to do as an industry. So much for getting back to normal.

Be safe!

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Al abama Tu rf Tim es > >> Spri ng 2021

is finally here, perhaps the most anticipated change of the calendar in my lifetime. It seems everyone wants the world to become normal again. Chances are we will never be normal again. The world is a dynamic sphere, always changing, with surprises both good and bad around every corner. We have a new administration in DC and a very divided government and population. It appears the US population has become binary, you’re either on one side or the other with nothing in between. We have had 4 years of relaxed environmental regulations with the Trump administration and that will probably end abruptly with the Biden administration. In fact, our first new hurdle on the environmental regulation front is at our doorstep.

Back in 2017 the EPA proposed additional training for pesticide applicators. The rule was blocked by lawsuits and the Trump administration put the rule on hold. It has now been revived and will go into effect within the next year. The goal was to have everyone who applies plant protectant products under the supervision of a certified T&O holder to have testing and training and demonstrate a level of competency.

This means that everyone who applies fertilizer to the lawns, sprays roundup with a pump-up sprayer in flower beds, or uses wetting agent tablets in a hose end applicator needs to have state regulated competence. This is actually a good idea if you look at the big picture of environmental stewardship, but it adds another layer of work and documentation to the process of operating in our industry. This proposal is being called the Non-Certified Applicator rule. I have a problem with that title.

What does this mean to those in the turfgrass industry? In most cases, it probably doesn’t change much in your operations.

Simply stated, anyone who handles or applies any product on their clients’ property must be recognized by the state as being competent and trained to do so. There should already be a certified T&O license holder on the staff and at many companies there are several on the staff. If you only use the

Recent Events >>>

ATA 2021 Calendar of Events

As The

Road Shows went into uncharted territory this January, literally zooming into the future. Due to the Covid Pandemic, it became obvious in November that we would not be in a place where we could offer our successful series of Road Shows “live” this winter. Our educational speakers did not have travel sanctioned by their universities, and even reserving most venues became problematic.

we approach Spring in 2021, many things remain uncertain with the COVID Pandemic. Hopefully by summer, the vaccination program will have proceeded to the point where we can resume our normal activities. While we have no firm date, we believe the Auburn Turfgrass Research Field Day will be able to take place in July and we will schedule our Poa Annua Classic around that date. As soon as we have confirmation we will share with our membership.

The ATA Board made the decision to offer our program virtually. Many of our members rely on these road shows as an opportunity to get their pesticide recertification points for the year, and we didn’t want to let them down. The program was arranged on Zoom webinar and offered twice, on January 6th and 27th. While there were a few glitches and operator error in using the new technology, it really went quite well overall, with some even commenting that they preferred the format to the “live” event!

Al ab ama Tu rf Tim es > >> Spring 2021

We would like to take this opportunity to say a special thanks to John Nabors who gave free instruction regarding the ins and outs of Zoom webinar.

Also, to Tricia Roberts and James Horton, who worked with me to get the program off the ground. We owe all our speakers a big round of applause.

They have become very proficient in the use of this technology and provided us with the recordings we needed to set up the Show. We also especially appreciate our education advisor, Dr. Dave Han for taking extra time to appear live and answer questions at the end of the presentations.

The Deep South Turf Expo

is scheduled for November 1–4, 2021 at the Mississippi Coast Convention Center in Biloxi, MS. Our Annual Business Meeting will be held there on November 3rd!

If you are like me, you are really ready to get back to normal, and we hope to bring you the Road Shows live in our six cities next year. In the meantime, we feel blessed to have the technology to make the presentations possible. Thank you all for your patience and we hope to see you soon! In the meantime, take care and stay safe.

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Keep up-to-date with event news by following Alabama Turfgrass Association and The Turf Zone on social media!

Recent Events >>> Continued

Starting the Holidays Right!

SPONSOR APPRECIATION SPORTING CLAY SHOOT Returned to Lower Wetumpka Shotgun Sports Club in December

The

Al ab ama Tu rf Tim es > >> Spring 2021

Alabama Turfgrass Association hosted the Annual Sponsor Appreciation Sporting Clay Tournament on December 14, 2020.

Members enjoyed some downtime at this event, and it was a great way to say thank you to our sponsors! The Lower Wetumpka Shotgun Sports Club, just north of Montgomery offered excellent facilities. As usual the event began with a delicious lunch provided by Down the Street Catering. Prizes were awarded at the conclusion of the tournament.

All sponsors’ attendance is complimentary, but they must pre-register. Participants are encouraged to bring their own gun and enough ammo for a 100-round event. Gun rental and ammunition are available at Lower Wetumpka. We hope you will make plans to attend this event next year!

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Cover Story >>>

New Herbicides FOR 2021, PART I

By Scott McElroy, Ph.D. – Professor, Department of Crop, Soil, and Environmental Sciences Jim Harris – Research Associate, Department of Crop, Soil, and Environmental Sciences, Auburn University The following article will discuss select new products that will be available for turfgrass industry use in 2021. The discussion of these products is not an endorsement of the products and exclusion of products that may be newly available is not opposition to those products.

Products discussed have been researched in Dr. McElroy’s research group and some available data is presented. Always follow the label regardless of what any article may say about a product. The label is the law.

N

ew herbicide products do not necessarily mean new active ingredients. New herbicide product names may simply be repackaged active ingredients or novel mixtures of previously available active ingredients. Novel active ingredients are a rarity with respect to new herbicide products.

The lack of a novel active ingredient does not necessarily mean that the products do not bring a new control angle to the turfgrass industry. Novel combinations of older active ingredients can provide additive or even synergistic herbicide effects and can broaden the spectrum of weeds controlled. But with new combinations it is important to understand the activity of individual active ingredients contained in the products.

FIGURE 1: Small hop clover control with Coastal.

Al ab ama Tu rf Tim es > >> Spring 2021

Coastal Coastal herbicide is a new combination of older products – imazaquin, prodiamine, and simazine. Imazaquin previously labeled as Image can now be purchased as the stand alone product Scepter T&O. Prodiamine was first labeled as Barricade and simazine was first labeled as Princep (There are other product names, it is simply easier to refer to the first product name used).

New herbicide mixtures primarily target new combinations of post herbicides — Trimec-type herbicides or herbicides with mixtures of sulfentrazone (Dismiss) and quinclorac (Drive).

Echelon is a combination of prodiamine and sulfentrazone, pre and post, respectively, but few (if any) others exist. Coastal is another unique combination because it also combines both pre and post herbicides. Prodiamine is strictly a preemergence herbicide with no postemergence activity. Simazine is used for post winter weed control, primarily Poa annua, but it can provide 14–28 days of residual. Imazaquin is a postemergence herbicide with minimal residual activity.

Coastal is labeled for use on bermudagrass, centipedegrass, St. Augustinegrass, and zoysiagrass. Like the name implies, it is primarily targeted at warm-season turf along the gulf coast.

Being registered for weed control on the four-primary warmseason grasses is important for lawn care because it does not require the changing of products from one turfgrass lawn to the next.

Research conducted in 2019–2020 evaluated Coastal in September and October for Poa annua and winter annual broadleaf control. Coastal was applied at 32 or 64 fl oz/a with or without 14

metsulfuron (MSM) at 0.5 oz/a. A comparison treatment Specticle at 6.5 fl oz/a plus metsulfuron at 0.5 fl oz/a was included.

•A ll treatments controlled Poa annua completely regardless of split or single applications (data not shown). The additional benefit of Coastal is that it also provided effective control of the annual broadleaf, small hop clover (Trifolium dubium; Figure 1). Coastal with and without metsulfuron reduced hop clover cover to 2–4%, while hop clover cover was > 25% in non-treated plots.

The combination of residual activity from prodiamine and simazine combined with the postemergence activity of simazine and imazaquin likely lead to the effective control.

Al abama Tu rf Tim es > >> Spri ng 2021

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Cover Story >>> Continued

Vexis Vexis is a new herbicide product containing the new active ingredient pyrimisulfan. It is a sedge control herbicide with excellent cool and warm-season turfgrass safety. It is also labeled for golf and residential turf. Vexis is currently only sold as a granular. A sprayable formulation is currently in the registration pipeline.

There are many herbicide options for sedge control in turf. Twenty to 30 years ago, herbicides for sedge control in turfgrass were primarily limited to MSMA and Basagran (bentazon). Now, several ALS-inhibitors are available including Sedgehammer (halosulfuron), Monument (trifloxysulfuron), Certainty (sulfosulfuron), Celero (imazosulfuron), and Katana (flazasulfuron). Also, Dismiss (sulfentrazone) is a PPO-inhibitor that provides a different mode of action for sedge control in cases of herbicide resistance.

Vexis is an ALS inhibiting herbicide, so it does not bring a new mode of action to the table for sedge control. The current benefits of Vexis are that it can be applied as a granular and with a high level of cool and warm-season turfgrass safety.

Safety across cool and warm-season turfgrass is beneficial for the transition zone where such grasses may be directly adjacent to each other. Expect new herbicides in the future that use pyrimisulfan in a novel mixture to gain a greater spectrum of weed control.

Doveweed plot cover was approximately 20 to 30% at the time of application on 24 June (Figure 2). Following sequential applications, all treatments reduced doveweed cover to 0 to 3% cover two weeks after the second applications. Three applications of Scepter plus Dismiss at a lower rate was not more effective when rated on 13 September than two applications at a higher rate (Figure 3). All treatments were statistically equivalent in doveweed plot cover (2–6%) as rated on 13 September while non-treated plots had approximately 80% plot cover. Based on past research and observations, all treatments provided excellent doveweed control.

Final Thoughts This article is meant to highlight a select set of new herbicides entering the turfgrass market. Expect follow up articles this year discussing other new products.

FIGURE 2

Al ab ama Tu rf Tim es > >> Spring 2021

Scepter T&O Imazaquin was first used in turfgrass under the trade name of Image. Since then, the “Image” name has been re-branded for the home lawn care market and an Image branded product can contain atrazine, MSMA (in the past), or other active ingredients. Image is less of a herbicide brand name and more of a marketing strategy for herbicide products in the consumer herbicide space.

Scepter T&O has replaced Image as the standalone product containing only imazaquin. There is nothing new about Scepter T&O, only the name has changed. Imazaquin is a unique, probably overlooked product. As products age, marketing budgets do not keep up and consumers are attracted to the newer, flashier products. Newer products are not necessarily better, but they can highlight some of the issues with an older active ingredient.

Imazaquin is one of those active ingredients that was exposed with the introduction of new products. While it has sedge, broadleaf, and cool season grass activity, one of the needs of newer products is broad spectrum activity and excellent turfgrass safety. Imazaquin is effective for sedge control, but it really needs a tank-mix partner like MSMA for consistent effectiveness. It is not broad spectrum for broadleaf weed control either and Poa annua control can be inconsistent.

Research was conducted in 2019 to evaluate combinations of Scepter T&O for doveweed control. Treatments included Scepter 5.7 oz/a plus Dismiss 4.0 fl oz/a applied three times (24 June, 16 July, 5 August), Scepter 8.5 oz/a plus Dismiss 6.0 fl oz/a applied two times (24 June, 16 July), Scepter T&O at 8.6 oz/a plus metsulfuron at 0.5 oz/a applied two times (24 June, 16 July), and Celsius at 4.9 oz/a applied twice (24 June and 16 July). All treatments contained non-ionic surfactant and were applied at 30 gallons per acre spray volume.

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FIGURE 3 Non-Treated

Scepter 5.7 oz/a + Dismiss 4.0 oz/a ABC

August 9, 2019 – 4 Days After C Application

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Feature Story >>>

TAKE-ALL ROOT ROT:

A Detrimental Root Disease of Bermudagrass Putting Greens

By Maria Tomaso-Peterson, Ph.D and Aaron Tucker, MSc., Mississippi State University Cameron Stephens, Ph.D candidate, North Carolina State University

Al ab ama Tu rf Tim es > >> Spring 2021

T

ake-all root rot (TARR), as the name indicates, is a disease that affects roots, stolons, and rhizomes. This disease is widespread on ultradwarf bermudagrass greens throughout the transition zone and subtropical climates, including Alabama. However, TARR is also active in dwarf bermudagrass greens and sod production fields where bermudagrass putting green cultivars are grown. Until recently the causal agent of TARR was identified as Gaeumannomyces graminis var. graminis – or Ggg. We initiated research in 2012 in the Turfgrass Pathology lab at Mississippi State University (MSU) to get a better understanding of the ectotrophic rootinfecting (ERI) fungi associated with this disease — originally referred to as bermudagrass decline (BD). We identified three novel ERI fungi, G. nanograminis (Gn), Magnaporthiopsis cynodontis (Mc), and Candidacolonium cynodontis (Cc), that formed a complex with G. graminis infecting roots in bermudagrass (BG) putting greens. These fungi do not discriminate between Tifdwarf, 328, or other ultradwarf bermudagrasses.

Parallel research conducted by Cameron Stephens and Dr. Jim Kerns at North Carolina State University (NCSU) identified a fifth ERI fungus, G. graminicola (Ggram), associated with rootrot and symptoms of TARR. ERI fungi colonize the outer surface of roots, stolons, and rhizomes and produce distinct structures, readily identifiable with the aid of a microscope. They are characterized by the formation of dark brown to black runner hyphae and growth cessation structures on the surfaces of roots, stolons, and rhizomes. Infection hyphae originate from lobed hyphopodia (Fig. 1).

The foliar symptoms of TARR first appear as irregularshaped, chlorotic to white patches up to 3.0–ft in diameter.

Foliar symptoms of chlorosis/necrosis progress upwards from the point of infection near the crown of the plant to the leaf tips. The chlorotic to white patches may be solitary or coalesce with neighboring patches to create large, irregular areas within a green. A general thinning with the patches or along the

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margin of the green may result if the disease is left unchecked (Figs. 2–3). These symptoms may be confused with other foliar diseases such as mini ring or nematodes.. Therefore, it is important to check the root system of affected plants. These roots, stolons, and rhizomes will appear dark brown to black.

Black lesions may be observed on the stolons and roots. Overall, the roots will be very short, 0.5–in., brown, rotted, brittle and lack secondary roots and root hairs.

FIGURE 1: Infection hyphae originate from lobed hyphopodia

FIGURES 2–3: Chlorotic to white patches appear solitary or coalesce with neighboring patches.

Al abama Tu rf Tim es > >> Spri ng 2021

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Feature Story >>> Continued

GROWERS OF QUALITY TURF SINCE 1987

COOSA VALLEY TURF FARMS LLC

Take-all root rot symptoms occur during or immediately after warm to hot, humid periods in the late summer or early autumn when the day length shortens. The chlorotic patches tend to persist into the winter months when greens are covered to protect from freezing temperatures. In dormant BG greens, the remnant patches are usually obvious, becoming more conspicuous during spring green-up, and fade as vigorous BG growth resumes in the early summer. TARR symptoms are not typically observed during the summer months, but does that mean the roots are void of ERI fungal infection? In 2017–18, MSc. student at MSU, Aaron Tucker, conducted an extensive survey of ERI fungi associated with BG roots from two putting greens at the MSU golf course. One green was considered healthy or asymptomatic and the other had a history of TARR or BD. We sampled 68 areas of interest (AOI) from the healthy green and 66 AOIs from the TARR green. The roots were collected from annual July core aerification events in both years. A rapid molecular assay was developed specifically to identify the four ERI fungi of interest, Gg, Gn, Mc, and Cc. In general, at least one ERI fungus was identified in each AOI from both greens.

Gn had a high frequency of occurrence (FO) in the healthy green and Gn had a higher FO in the TARR green. Mc was identified in the roots of nearly all AOIs from both greens and Cc was identified in approximately 50% of AOIs in both greens each year. We also observed the ERI fungi formed a complex at a high frequency within sampled roots. In the healthy green in 2017, 7% AOIs had a fungal complex composed of the four ERI fungi and in 2018 50% AOIs had a Gn, Cc, and Mc complex.

Multiple complex variations were observed in the TARR green in both years. The four ERI fungal complex was observed in 7.5% and 15% AOIs for 2017 and 2018, respectively. A three ERI fungal complex

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Al ab ama Tu rf Tim es > >> Spring 2021

TABLE 1: The effective concentration to inhibit colony growth by 50%, EC50 (ppm), of each ectotrophic root-infecting fungus when exposed to commercial fungicides at 79°F in the dark for 7 to 14 days.

Thiophanate-methyl y

Fluxapyroxad

Propiconazole

Pyraclostrobin

Gaeumannomyces graminis (DR1-4)

15.6 ab B

>100.0 a A

11.8 b BC

7.7 b C

Gaeumannomyces nanograminis sp. (GSGC15-4)

27.0 a BC

>100.0 a A

9.2 b C

54.1 a B

Candidacolonium cynodontis (HP24-3)

2.3 b C

>100.0 a A

60.8 a B

4.7 b C

Magnaporthiopsis cynodontis (RS7-2)

17.8 ab B

—

79.4 a A

8.5 b B

Magnaporthiopsis cynodontis (RRFCHMP1-3)

12.2 ab B

>100.0 a A

19.9 b B

13.8 b B

z y

20

z

Means within column followed by the same lowercase letter are not significantly different according to Tukey’s HSD p ≤ 0.05.

Means within rows followed by the same capital letter are not significantly different according to Tukey’s HSD p ≤ 0.05.

FIGURE 4 70.0 a

Mycelial growth (mm)

60.0

Gg

Gx

Ggram

Mc

Cc

50.0

a

a

a b

a

b

40.0 30.0

cd

a

c

ab

20.0

bc a

10.0 0.0

b a

a

a

a

a

59

b

b

d c bc

a

50

d cd

a

c

68

77

86

c

95

Temperature (°F)

Growth of Gaeumannomyces graminis (Gg), Gaeumannomyces nanograminis (Ga), Gaeumannomyces graminicola (Ggram), Candidacolonium cynodontis (Cc), and Magnaporthiopsis cynodontis (Mc) at different incubation temperatures. Means followed by the same letter within temperature are not statistically different according to Fisher’s Protected LSD test at P<0.05.

FIGURE 5

Average soil temperatures of the top 4.0 inches in Starkville, MS. Similar temperatures are most likely found along the I-20 corridor of Alabama, including Tuscaloosa and Birmingham. The red bars indicate the optimal temperature range for ERI fungal growth.

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Al abama Tu rf Tim es > >> Spri ng 2021

consisting of Gn, Mc, and Cc was observed in 27% AOIs in 2018. Previous research at MSU and most recently at NCSU showed the individual ERI fungi express variable levels of aggressiveness on bermudagrass roots. This indicates each ERI fungus alone can cause root rot. They also have different levels of fungicide sensitivity, growth rates, optimal temperatures. In vitro fungicide sensitivity assays to screen the ERI fungi were conducted independently by Tucker and Stephens. Both showed the ERI fungi are not sensitive to succinate dehydrogenase inhibitor (SDHI) fungicides such as fluxapyroxad, penthiopyrad, and isofetamid. The ERI fungi showed moderate levels of sensitivity to the strobilurin (QoI) and demethylation inhibitor (DMI) fungicides compared to the SDHIs with azoxystrobin and pyraclostrobin having the greatest inhibitory effect on fungal colony growth.

Tucker’s results at MSU calculated the effective concentration to inhibit 50% (EC50) colony growth. No fungicide completely inhibited fungal growth (Table 1).

How do these results transfer to fungicide control in a BG putting grass?

Take-all root rot pathogen growth was evaluated at 50, 59, 68, 77, 86, and 95°F to determine optimal growth temperature of each organism. In general, all TARR pathogens grew optimally between 77 and 86°F (Fig. 4). Optimal growth temperature for Gg, Gn, Ggram, Cc, and Mc was 78.4, 75.4, 76.3, 91.0, and 80.1°F, respectively.

Historically, TARR has primarily been viewed as a fall season issue with applications for TARR management typically beginning in late September-October.

However, results from this study indicate these pathogens are growing optimally and potentially causing the most damage to bermudagrass roots through the summer months. That damage may manifest in the Fall and Spring as characteristic TARR symptoms when adverse bermudagrass growing conditions such as low light and cooler temperatures are present.

By that time, the damage has been done, the pathogens are not actively growing, and curative fungicide applications may be futile. Ultimately, this information warrants earlier fungicide applications than traditionally applied. For fungal growth to be inhibited, the fungus must be actively growing to absorb the fungicide. Corresponding the optimal growth temperature information from this study to the soil temperature data at a 2-4-in. depth from Starkville, MS (Fig. 5), we can see TARR pathogens may be growing optimally from May-Sept in 2019 and June-Sept in 2020. Ideally, this is when we should be applying fungicides for TARR management.

Feature Story >>> Continued

Fungicide application timing research has also been conducted at NC State to validate the previous claims under field conditions. Field studies were initiated evaluating Tartan application timing for TARR management. Plots received four applications of Tartan on a 21-day interval with staggered start dates. All applications were watered in with 1/8th inch post-application irrigation. Application start dates were Timing 1 (15 July), Timing 2 (5 August), Timing 3 (26 August), Timing

4 (16 September), and a non-treated control (NTC). On 6 Jan 2020, Tartan applications initiated on Timing 2 (5 August 2019) provided the best TARR control and Timing 3 (26 August 2019) provided moderate disease suppression (Fig. 6). However, if we look at the area under the disease progress curve, or disease progression over time in 2020, Timing 1, Timing 2, and Timing 3 all significantly reduced TARR severity compared to the nontreated control (Fig. 7). Tartan applied on Timing 4 did not

FIGURE 6 Take-all root rot severity on 6 January 2020 influenced by various Tartan application initiation dates. Timing 1=15 July, Timing 2=5 August, Timing 3=26 August, Timing 4=16 September, NTC=Non-treated control.

Means followed by the same letter are not statistically different according to Fisher’s Protected LSD test at P<0.05.

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Continued <<< Feature Story

reduce TARR compared to the non-treated control. Timing 4 was most likely applied too late when the pathogens were not actively growing.

A similar study was conducted evaluating Maxtima and Navicon application initiation timing for TARR management.

Plots received two applications of either Maxtima or Navicon on a 21-day interval with staggered start dates. All applications were watered in with 1/8th inch of post-application irrigation.

Treatments (initiation date) were Maxtima 1 (25 August), Maxtima 2 (25 October), Navicon 1 (25 August), Navicon 2 (25 October), and a non-treated control (NTC). Similar to the Tartan application timing results, the earlier applications of either Maxtima or Navicon provided the best TARR suppression on 8 October 2020, 29 October 2020, and 19 November 2020 (Fig. 8). Disease progression over time was the lowest for the Maxtima 1 and Navicon 1 application timings (Fig. 9) suggesting the earlier application start dates provided the best TARR suppression.

In general, initiating fungicide applications for TARR earlier than traditionally applied may provide greater TARR control.

The earlier application timings of Tartan, Maxtima, and Navicon provided greater control of TARR compared to the later application timings and the non-treated control in Raleigh, NC. Field trial results presented here align well with the optimum in vitro growth temperature study. In Central Alabama, targeting TARR application initiation for late May-mid-June may provide the greatest disease control. However, soil temperatures should be monitored in your area of Alabama to make the most informed decision.

FIGURE 7

Take-all root rot severity influenced by various Maxtima and Navicon application initiation dates. Maxtima 1=25 August, Maxtima 2=25 October, Navicon 1=25 August, Navicon 2=25 October, NTC=Non-treated control. Means followed by the same letter within rating date values are not statistically different according to Fisher’s Protected LSD test at P<0.05.

FIGURE 9

Take-all root rot severity over time (area under disease progress curve; AUDPC) influenced by various Maxtima and Navicon application initiation dates. Maxtima 1=25 August, Maxtima 2=25 October, Navicon 1=25 August, Navicon 2=25 October, NTC=Non-treated control. Means followed by the same letter for AUDPC values are not statistically different according to Fisher’s Protected LSD test at P<0.05.

23

Al abama Tu rf Tim es > >> Spri ng 2021

Take-all root rot severity over time (area under disease progress curve; AUDPC) influenced by various Tartan application initiation dates. Timing 1=15 July, Timing 2=5 August, Timing 3=26 August, Timing 4=16 September, NTC=Non-treated control.

Means followed by the same letter for AUDPC values are not statistically different according to Fisher’s Protected LSD test at P<0.05.

FIGURE 8

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“Be Friendly to Everyone, Whether They Purchase Your Brand of Equipment or Not!”

Al ab ama Tu rf Tim es > >> Spring 2021

M

ickey Pitts was born on Christmas Day in 1948, in Red Level, Alabama. Raised on a farm near Andalusia, Mickey had two sisters and no brothers, allowing him to claim the title of ‘favorite son.’ He often helped with farm chores, instilling a love of agriculture and a skill set that would inspire his later career.

Mickey graduated from Red Level High School and attended just one year of junior college before being drafted by the military. He decided then to enlist in the Air Force for four years, hoping to avoid deployment to Vietnam. Nevertheless, he deployed to Vietnam in January of 1970, serving 13 months overseas. Mickey was a crew chief on fighter jets and was under fire many times, but fortunately, made it home intact. When his active military career ended, Mickey joined the Alabama National Guard and served with them for many years.

Upon his return to the United States, Mickey met his future wife, Jenny. They married in 1971 and have two daughters, Amy and Ashley.

Mickey’s career in the turf industry started when he left the Air Force and decided to return to his roots.

He started working with Don Cotton at Turf Pride in the 1980’s. Mickey found that his childhood on a farm made him a good fit for turf sales. He worked at Neary after Turf Pride, then settled at Tieco in 1993.

After working at Tieco for almost a decade, Mickey moved to Beard Equipment in 2001. Soon afterwards the World Trade Center was destroyed in a terrorist attack. Mickey, still in the Alabama National Guard, expected to be called into service in the Middle East, but fortunately, he remained stateside and retired from the National Guard in 2010.

CONTINUED ON PAGE 26

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Prior to joining Beard Equipment, Mickey had been acquainted with Herman Bloch and when Beard began selling John Deere equipment, Mickey really found his sales footing. He received a John Deere ring and many other honors from John Deere over the years. Mickey’s sales strategy is to be friendly with everyone — whether they are purchasing equipment or not! “Personability and kindness to potential customers can help overcome sales challenges most of the time. Convincing potential customers that the equipment is worthwhile can be difficult, but a good product and a friendly face overcomes most obstacles, according to Mickey. “It’s simple, but the key to sales success is kindness.”

During his career, Mickey has traditionally enjoyed playing golf. He doesn’t get out to the course much anymore, but that doesn’t mean that he has slowed down — he spends time with his granddaughters, Lily and Ingram. He has also increased his travel, visiting everywhere from Alaska to Key West with his wife and friends in the past few years.

Mickey reflects on his career thus far by thanking his coworkers — “The guys I’ve worked with have always been a blessing in my life.” Mickey has never met a stranger — he loves his job and the people he does it with!

The Alabama Turfgrass Association has been blessed to have Mickey as a member for many years, and he has also served on the ATA board and then the executive board as Treasurer and Vice-President. Thank you, Mickey for your service to your country, your employers, your customers and your ATA Family!

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Al ab ama Tu rf Tim es > >> Spring 2021

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