A

www.sportsturfonline.com

ANNUAL BLUEGRASS is a winterannual grassy weed with a bunch-typegrowth habit (Figure 1) that often formsdistinct patches or clumps in establishedturf. Annual bluegrass has many identify-ing characteristics including: (1) leavesthat are folded in the bud, often partiallywrinkled, and end in a boat-shaped tip(Figure 2); (2) a long, membranous,slightly pointed ligule; and (3) a panicle-type seedhead that is triangular in shapewith spikelets bunched toward the end ofthe inflorescence (Figure 3).

Annual bluegrass seed will begin togerminate in autumn when soil tempera-tures fall below 70 degrees F. In the tran-sition zone, this can be as early asAugust. At the same time that annualbluegrass seed is germinating, bermuda-grass growth in the transition zonebegins to decrease, resulting in less com-petition against weed encroachment.Dormant bermudagrass turf is oftenoverseeded with cool-season species, likeperennial ryegrass, to improve playabilityand aesthetics throughout the wintermonths, and to provide competitionagainst various winter annual weedspecies. On golf courses, Velocity(bispyrabic-sodium) can be used to con-

trol annual bluegrass in overseededbermudagrass turf; however, this is not asuitable option for sports turf managersas this product is not labeled for use on ath-letic fields. Thus, annual bluegrass con-trol programs for bermudagrass athleticfields should be implemented when anoverseeded turf species is not present.

Options for controlCultural Control. The best defense

against any type of weed invasion is tomaintain a dense, vigorous turfgrassstand. Cultural practices that maximizebermudagrass quality will allow the fieldto be competitive against potential weedinvasions. These practices include thingslike mowing regularly at an appropriateheight of cut, aerating regularly to providesoil conditions favoring root growth, andproviding the field with adequateamounts of fertilizer and irrigation water.

Herbicidal Control (preemergence).Numerous preemergence herbicides areavailable for controlling annual bluegrasson non-overseeded bermudagrass athleticfields. Research conducted at Tennesseehas shown that these materials performsimilarly when applied under the sameenvironmental conditions.

Preemergence herbicides must beapplied before seed germination in orderto work effectively. These materials do notstop seeds from germinating; rather, theyprevent seedlings from maturing into fullgrown plants. Thus, preemergence herbi-cides must be applied before seed germi-nation in order to work effectively.

Annual bluegrass will germinate when

Major points

>>FieldScience By Greg Breeden and Dr. James Brosnan

Managing Poa annua fornon-overseeded bermudagrassin the transition zone

• Numerous preemergence and poste-mergence options exist for control of annualbluegrass on non-overseeded bermudagrassathletic fields.

• Make sure bermudagrass is totally dor-mant when using non-selective herbicidesfor annual bluegrass control.

• Rotate herbicide modes of actionwhenever possible to decrease the potentialfor developing annual bluegrass herbicideresistance.

• An application of glyphosate tank-mixed with a preemergence herbicide inearly spring can provide preemergence crab-grass control as well as postemergence con-trol of annual bluegrass.

12 SportsTurf | March 2009

Below: Figure 1

SportsTurf 13www.stma.org

Figure 2 soil temperatures fall below 70 degrees F, which inTennessee is usually sometime in early September.However, temperatures can occasionally decrease dur-ing the month of August causing annual bluegrass togerminate earlier than normal. This “early germina-tion” is often the reason that preemergence herbicideapplications fail to control annual bluegrass. In thetransition zone, target preemergence herbicide applica-tions for mid to late August.

Preemergence herbicides should NOT be applied ifthere is any consideration of overseeding the field witha cool-season turfgrass species like perennial ryegrass(unless otherwise stated on the product label).

Herbicidal Control (postemergence). There aremultiple postemergence herbicides that provide effec-tive annual bluegrass control on non-overseededbermudagrass athletic fields. Postemergence applica-tions can be made any time after annual bluegrass seedhas germinated. Caution should be used when apply-ing postemergence herbicides close to the end ofbermudagrass winter dormancy. Some herbicides candelay spring green-up when applied close to the breakof dormancy.

Herbicidal Control (non-selective). Glyphosatecan be applied to dormant bermudagrass to providepostemergence control of annual bluegrass. Keep inmind that injury can occur to the bermudagrass if itis not totally dormant. Anytime an application of anon-selective herbicide, like glyphosate, is used forweed control it is integral that the bermudagrass turfis totally dormant (Figure 3). If the bermudagrass istransitioning into or out of dormancy serious injurycan occur.

Herbicidal Control (by tank-mixes). Combiningpre- and postemergence materials will increase theweed control spectrum of a single herbicide applica-tion. For example, should temperatures drop in the fallto the point where annual bluegrass seed begins to ger-minate, tank-mixes of pre- and postemergence herbi-cides can be applied to control annual bluegrass plantsthat have recently emerged and those that have not yetgerminated from seed.

If a glyphosate plus preemergence herbicide tank-mix is applied in late winter (February to early Marchin Tennessee), it can also provide preemergence controlof crabgrass the following spring. Tank-mixes of pre-

14 SportsTurf | March 2009 www.sportsturfonline.com

emergence herbicides andglyphosate have performed well in

research trials conducted at theUniversity of Tennessee.

Annual bluegrass has been found tobe resistant to certain herbicides. For

example, incidences of prodiamine resist-ant annual bluegrass have been reported in

Tennessee. Any herbicide program shoulduse a rotation of herbicides, each with differ-

ent modes of action, to decrease the likelihoodof developing herbicide-resistant biotypes.

Have a planSports field managers should always have a plan

for controlling annual bluegrass on their fields.The control strategy selected (preemergence,

postemergence, non-selective, or a combination ofthese) will in part be influenced by the schedule of fielduse. If fields are used heavily at one particular time ofyear there may literally not be enough time to apply an

herbicide. Additionally, the heavy foot traffic from theseathletic events could also reduce herbicide efficacy.

If the majority of play is during the spring for soccer,then preemergence herbicides applied in the fall may bethe most effective option for annual bluegrass control.On the other hand, if the field is used heavily duringthe fall for football, then postemergence or non-selec-tive control in the early spring may be a better option.

Multiple preemergence and postemergence herbicidesare available for controlling annual bluegrass on non-over-seeded bermudagrass athletic fields in the transition zone.Applying tank mixes of both preemergence and poste-mergence herbicides can help extend control throughoutthe winter and potentially into the spring. �

Greg Breeden is weed science extension associate andJames T. Brosnan, Ph.D., is assistant professor-turfgrassweed science at the University of Tennessee in Knoxville.For more information visit http://tennesseeturfgrassweeds.org.

FieldScienceFigure 3

SportsTurf 15www.stma.org

Wetness and wealth key foes of native soil fields

“Sometimes they spend moremoney on the paint scheme forthe endzones than they do onthe field itself.” – Powell

EEven the trustees who drive to board meetings in a Lexus knowthat financial times are tough. This is a good time for sports turfmanagers to talk dollars and “sense,” whether the conversationhappens at a school or a recreation department.Nobody is out beating on office doors to sell native soil

fields. Synthetic infill turfs have had a huge impact on the mar-ket. The reason is plain—a contractor might make $5,000 prof-it for crowning a natural field or even $20,000 for building one.But those Lexus-driving board members are going to write outa check for $100,000 profit to the contractor for a syntheticfield. So, which do you expect the contractor to push?“Don’t mistrust your contractor, just know how to talk to

him,” says A.J. Powell, turf specialist at the University ofKentucky. While he concedes there are many good places forsynthetic fields, he maintains that people need to take anotherlook at natural soil fields—especially from an economic pointof view.Cost of construction outweighs the maintenance cost sav-

ings gained by establishing a synthetic field. Powell figures theaverage annual cost of maintaining a natural soil field at about$22,000 for a custom company, a sand-based field at about

$40,000 and a synthetic infill at a minimum of $3,500. Thehigh cost of construction and maintenance of a sand-based fieldis perhaps beyond reason, especially when one considers theirfrequency of failure.Including laser grading to build a good crown in the center

of the field, natural soil fields are inexpensive to build, costingmaybe an average of $50,000, Powell told field managers at theOhio Turf Conference (OTF). Even a worn natural field willprovide good, soft footing. “And nobody has shown that amuddy field is unsafe to anyone, except the guy washing uni-forms,” Powell says.Put all that on one side of the ledger and balance it with a

$600,000 to $1,000,000 tag for a new sand field or new syn-thetic infill field.“Sand-based fields are just as expensive as artificial fields and

work no better than most natural soil fields,” Powell points out.When factoring in the cost of construction and maintenance,the natural soil fields will always be some $42,000 to $56,000per year less expensive than synthetic or sand-based fields.”Most of the money spent on an artificial field is getting rid

of excess rain water,” Powell says. Water is a problem on naturalsoils, too. But there are a lot of agronomic things a sports turfmanager can do to reduce the problem.

Courtesy of Gerald Landby, Carroll College

FieldScience By Curt Harler

16 SportsTurf | March 2009 www.sportsturfonline.com

FieldScience

Initial Const.

Maint. 1st yr

10 yr Maint.

10 yr Total

Avg Cost/yr

Current-Sand field

$40,000

$458,600

$458,600

$45,860

NewSand field

$1,000,000

$40,000

$458,600

$1,458,600

$145,860

New Infill(high end)

$1,000,000

$25,000

$326,190

$1,326,190

$132,619

Initial Const.

Maint. 1st yr

10 yr Maint.

10 yr Total

Avg Cost/yr

Soil FieldContract

$20,000

$229,358

$229,358

$22,936

Soil FieldDIY

$7,000

$80,275

$80,275

$8,028

New SoilField

$50,000

$15,000

$172,018

$222,018

$22,202

New Infill

$600,000

$3,500

$40,120

$640,120

$64,012

Initial Const.

Maint. 1st yr

10 yr Maint.

10 yr Total

Avg Cost/yr

New Soil

$50,000

$15,000

$172,018

$222,018

$22,202

CurrentSoil

$15,000

$172,018

$172,018

$17,202

New Sand

$600,000

$40,000

$458,600

$1,058,600

$105,860

New Infill

$800,000

$25,000

$326,190

$1,126,190

$112,619

Grass vs. Infill

Soil Based vs. Infill

Comparing Sand vs. Infill“Yes, natural fields can get sloppy. No, they are not alwaysuniformly aesthetic,” Powell concedes. “But there is a big costsavings by going with natural turf and doing it right.”

The starting blocksThe best place to start improving any natural soil field is to

work to get the field into as good shape as possible to start theseason. That may sound like Turf 101, but it is good advice.

“People like to play on a quality field. Yes, they may wipe itout. But that is just a fact of life,” Powell says. Whenever a reallygreat field is developed, there is enormous pressure for more andmore teams to use the field.

However, limiting use on the premier natural fields can cer-tainly help. This seems to be less a problem on baseball fieldsthan anywhere else. Baseball coaches have been successful at lob-bying to keep people off their fields. Perhaps they feel a closeraffinity with the actual field. Perhaps they can sell the importanceof “true” ball roll on the surface. Whatever the reason, baseballfields seem to have less wear and tear. As a result, they hold upbetter than football or soccer fields.

Perhaps big, rectangular fields simply lend themselves to moreuse: football, soccer, band practice, intramural games. But that’sno reason why the fields cannot be prepared well and maintainedwell.

“Sometimes they spend more money on the paint scheme forthe endzones than they do on the field itself,” Powell scoffs. “Ifyou have to cut costs, you should be talking about places otherthan the agronomics.”

Powell sees no reason why a native soil field should not be ableto carry one or two teams for two playing seasons per year—aslong as the field is dry. He says he has seen successful programshandle 70 events a year, again citing the importance of keepingthe field dry and not displacing the soil.

Water, athletics don’t mixNo coach today would deprive an athlete of water. However,

a good sports manager is better served by doing exactly that withthe field.

“Especially on football fields, traffic on wet soil displaces thesoil, destroys the soil structure and creates little birdbaths in thefield,” Powell says.

Can proper management reduce field wetness and soil satura-tion? “You betcha,” Powell says in his best Sarah Palin imitation.

Many agronomists have noted the money that could be savedif football games were postponed in foul weather the way base-ball games are called.

“There is a price to repairing the field, and you have to teachyour administrators what that cost is,” Powell advises.

Irrigation often is more the problem than the solution.“Don’t over-irrigate,” Powell says. In fact, he would go so far

as to remove the automatic clocks on irrigation systems in manyparts of the country. Grounds managers would look at irrigationdifferently if they had to go out and turn some knobs every time

Contractors Always Sell Grass First Really ??•Even if a new grass field may only net $5,000 profit•Knowing the risks of a grass Grow-In vs. an engineered system that can performimmediately•Surface performance unquestioned•Surface performance identical to the elite competitors

Contractors Always Sell Grass First Really ??•Few hidden costs with Engineered system•Easy to minimize maintenance costs of syn. Infills –some spend zero dollars.•Easy to exaggerate maintenance costs of grass –what the costs have been orshould be.

Figures provided by Dr. A.J. Powell, University of Kentucky

www.sportsturfonline.com

FieldScience

they wanted to water their fields.Anticipate rainfall, Powell says. “Dryness is not deadly. Grass

does not die from dryness, at least not quickly.”A turf manager who anticipates rainfall should turn off the sys-

tem. “You cannot afford to have the field wet before a rain,” hesays. He says that, if managers treated water as a line item in theirown budgets then they probably would not be so liberal with it.

Any manager who is starting to see depressions in the fieldalready has a field that has gone too far. Depressions must berepaired each year, even the first year after the field is constructed.

A simple crown, yes, even on a soccer field, will take care ofmost water problems.

Good sideline drains are a must. Most field managers know itdoes not take too much effort to get the water off the field in thearea between the hash marks. But, that water must have some easyplace to go quickly. Good sideline drains are a must for all fields.Sleeve drains work but unless the water gets through the soil anddown into the drains, they may be totally ineffective, or effectivefor only a year or two.

Destroying soil structure starts a landslide of problems. Asandy topdress helps, of course, but there is more to keeping afield dry than that.

“Build tough verdure,” Powell says. A good, dense stand of

grass will do much to remove water from a field. In sports turf,normal evaporation is too slow to keep a field dry enough for play.A plant with a deep root system will help remove a lot of water,and also maintain surface soil integrity, he adds.

Stick to the basics and keeping water off the field becomesstraightforward.

Start with an annual renovation. Raise the height on themower as far as the coaches will allow. Do a good job of crabgrassand broadleaf weed control. Give the turf the nitrogen it needs tothrive, but don’t over-do it. Core regularly.

Powell says that, even if a field is being cored, it probably is notbeing cored enough. “This is especially true in practice fields andpark and recreation fields.”

He says coring is better than spiking or the other commonlyused methods aimed at getting water into the ground. The prob-lem with small-tine, solid coring is that, as soon as the soil getswet, it quickly closes in around the hole and there is little oppor-tunity for the water to flow down.

“If you must solid tine, it is only beneficial when the soil canbe shattered, but it must be really, really dry,” Powell told the OTFaudience. While it is more difficult to core dry soil, the effect ofthe shattering will last longer. That said, he still likes to see regu-lar 2- or 3-inch core aeration.

18 SportsTurf | March 2009

SportsTurf 19www.stma.org

To get more robust grass plants, makethem taller, he says. Before the coachscreams his head off about slowing downhis players, let him know that researchshows there is no difference between a1.5-inch, 2-inch or 3-inch cut height andrunner speed on the field. This does not,however, apply to ball roll on a soccerfield.

While mowing with a reel mower willmake the field look nice, doing the jobwith a rotary machine is just fine for mostuses.

Another curse of over-irrigation is thatit increases the number of times you mustmow. While one’s first thought might bethe labor or fuel required, Powell is moreconcerned about the effect of mower com-paction.

Extra mowing leads to compaction,which causes weaker plants with shorterroots, which requires more irrigation,which leaves a wet soil, which causes morecompaction. The downward spiral contin-ues until the field is very fragile.

“You have no choice; your job is watermanagement,” Powell says.

Lastly, when it comes time to reseedthe field, Powell advises using a “fast”grass. In areas where bermudagrass isappropriate, it is the variety of choice. Herecommends perennial ryegrass anywhereelse.

“A lot of TV venues that say they arebluegrass fields are bluegrass no longer,”Powell says. “Maybe they were at one timebut after a few years and several renova-tion seedings, they no longer have muchbluegrass.”

But those well-managed, well-drainedfields look good. And that proves thepoint that, with proper management, alocal native soil field can look just as goodas anything from a big-budget program.For decades we have had many greatnative soil fields maintained on relativelylow budgets, so why can we not do thatnow?” Powell asks. �

Curt Harler is a veteran free lance writeron turf and agricultural topics. He can bereached at curt@curtharler.com.

M

20 SportsTurf | March 2009 www.sportsturfonline.com

FieldScience J.T. Brosnan and G.K. Breeden

MONOSODIUM METHANEARSON-ATE (MSMA) is a commonly used herbi-cide in warm-season climates. Since the1960s, this product has been used tomanage infestations of various crabgrassspecies (Digitaria spp.), as well asgoosegrass (Eleusine indica) and dallis-grass (Paspalum dilatatum) in warm-sea-son turf.MSMA, an organic arsenical herbicide,

contains an organic form of the elementarsenic. In its organic form, arsenic is rela-tively non-toxic. For example, the herbi-cide MSMA is far less toxic than aspirin(see http://avogadro.chem.iastate.edu/MSDS/aspirin.htm or http://www.cdms.net/LDat/mp47P000.pdf ). However, inan inorganic state, arsenic can be highlytoxic. It is important to note thatMSMA only contains organic arsenic.Furthermore, research has continuallyshown that MSMA is tightly bound to soilorganic matter and is not readily leached.However, water samples from two golf

courses in Florida tested high in arsenic in2006. This spurred a ruling by the U.S.Environmental Protection Agency (EPA)to cancel the registration of MSMA in allaspects of agriculture, including turfgrass

management. There was a concern thatorganic arsenic from MSMA could con-vert into the more toxic, inorganic, formin the environment.Multiple public comment periods fol-

lowed the ruling and the response fromvarious facets of agriculture was over-whelming. The MSMA task force, analliance of chemical companies that man-ufacture the product and the cottonindustry particularly, led the charge.Concerns were raised on a number ofissues about the ruling, particularly thatno information was provided regardingthe type of arsenic detected in the water(i.e., organic or inorganic), the source ofthe arsenic found, and that there was noway to conclusively say that the arsenicwas from applications of MSMA.

Latest ruling on MSMA use in turfOn January 16, 2009 the EPA and the

MSMA task force announced the finaldecision regarding the use of MSMA inturf. Sports turf was not deleted in theJanuary ruling; however, considering itdid not receive the same exemption thatwas provided to golf courses and sodfarms, use on athletic fields will bedeleted after December 31, 2010, perthe EPA’s original ruling in August of2006. It is important to note that theJanuary 2009 ruling also indicated that itwill be illegal to apply MSMA in the stateof Florida, regardless of use site, afterDecember 31, 2010.Golf courses will continue use of

MSMA through December 31, 2013.Newly constructed courses will beallowed one broadcast application, andexisting courses will be able to use MSMAonly as a spot treatment providing thatspots are less than 100 square feet and no

more than 25% of the course is treatedwithin a given year.Sod farms will be able to use MSMA

through December 31, 2013 as well. Twobroadcast applications of MSMA will beallowed per crop, and a 25-foot bufferstrip will be required for farms borderingpermanent water bodies.The latest ruling deleted “residential

turf” as a legal MSMA use site. Thus,lawn care operators will not legally be ableto apply the product after December 31,2010.

What’s next?Before 2013, the EPA will conduct an

external review of the scientific informa-tion outlining the risks posed by inorgan-ic arsenic in the environment. The use ofMSMA will continue beyond 2013should this review conclude that there areno health risks evident from applicationsof MSMA on golf courses and sod farms.EPA will also review the role that MSMAplays in weed resistance managementbefore making a decision about usebeyond 2013.The loss of MSMA will certainly make

managing weeds in warm-season turfmore difficult, and inevitably, moreexpensive. Research is continually evalu-ating new compounds, as well as combi-nations of existing compounds, that willhelp soften the blow. To follow the latestresearch being conducted at theUniversity of Tennessee, visit http://ten-nesseeturfgrassweeds.org. �

James T. Brosnan, Ph.D., is assistantprofessor-turfgrass weed science at theUniversity of Tennessee in Knoxville. GregBreeden is the weed science extension associ-ate at UT-K.

Sports turf industry officially loses MSMA

Dr. James Brosnan is the new TechnicalEditor for SportsTurf magazine.

SportsTurf 21www.stma.org

Sports turf managers have slightly less than 2years to prepare their fields for life after MSMA.Focusing on a few key principles may help makethe transition easier.

Cultural practices. The best defense against anyweed invasion is healthy, dense, vigorous turfstand. Implementing cultural practices (aerifica-tion, fertility, mowing, etc.) to maximize turf den-sity will make fields less susceptible to weedencroachment. For example, goosegrass thrives incompacted, poorly drained soils. Soils of thisnature are commonly found in high traffic areas onsports fields where there is minimal turfgrasscover. Improving soil conditions in these areasthrough aerification and topdressing will reducethe likelihood of a goosegrass infestation.

Use the product while it is still available. Fieldmanagers dealing with infestations of annualgrassy weeds should use MSMA while it is still

legal to do so. Make a diligent effort to controlthese weeds now and then shift the focus to pre-emergence control of annual grasses after 2010.

This point especially rings true for dallisgrass,as there are no options other than MSMA forselective postemergence control of dallisgrass inturf. Herbicides such as foramsulfuron (Revolver)and trifloxysulfuron (Monument) will only providedallisgrass suppression, not control. Research iscurrently exploring new chemistries, as well ascombinations of existing chemistries, to provideselective dallisgrass control in both warm andcool-season turf.

Effective preemergence practices. The loss of aneffective, economical postemergence herbicide likeMSMA renders preemergence control of annualgrassy weeds more important than ever. Whenapplied correctly, preemergence herbicides such asprodiamine (Barricade), oxadiazon (Ronstar),

dithiopyr (Dimension), and pendimethalin(Pendulum) can provide effective control of annualgrassy weeds like crabgrass and goosegrass forextended periods of time. It is imperative thatthese materials be applied prior to the germinationof weed seed and are watered in after application.Most labels require ½ inch of irrigation or rainfallafter application. Research will be conducted in2009 at the University of Tennessee to evaluate theefficacy of the materials under simulated traffic.

The loss of MSMA will have a significant impacton the sports turf industry. Some may think thatDecember 31, 2010 is so far in the future that theyneed not worry about it now; today’s game ortomorrow’s practice is more important thanpreparing for something nearly 2 years away.Those individuals are wrong. Sports turf managerswho start preparing for the loss of MSMA now willreap the benefits later. �

Dealing with the ruling