Reduced sunlight results in decreased photosynthesis and therefore reduced plantvigor. Problems are compounded by low-cut greens that have very small leaf areaavailable to gather light. Moss invasion on a green is an indication that the properenvironmental conditions aren't present to grow good turf.

HelpingYourGreensMaketheGradeHere's a guide to help youevaluate the many factorsthat determine how yourgreens perform.

by JAMES FRANCIS MOORE

GOLFERSand their greens havehad a long and often tumultu-ous relationship. In fact, no area

of the course has a stronger influenceon the golfer's game, since between theapproach shot and putting, the greenscome into play on approximately 75%of the shots of a typical round of golf.Most golfers realize this and are quickto point their putters in disgust when-ever the green does not act as theybelieve it should, and they brag to theirneighbor when their club's greens arein top form.

Golf course superintendents andtheir greens have an even greater love/hate relationship. There is an old sayingin the superintendent's world - "Yourgreens are your resume." True enough,since players overlook a great deal onthe course when the greens are in goodshape, but will call for the superinten-dent's head when the putting surfacesare less than perfect (regardless of howgood the remainder of the course is).The golfer's perception of the role ofthe superintendent in providing perfectgreens is reflected in the tendency ofthe weekend hacker to refer to thesuperintendent as the greenkeeper -a term poorly suited to describe thevaried and often complex duties oftoday's professional golf course super-intendent.

Since golfers and superintendentsalike have such close relationshipswith their greens, it is beneficial for allconcerned to have a better understand-ing of why greens perform the way

they do. Truth be known, few golfershave any idea of the various factors thatdetermine the overall performance ofthe green. They hear stories of myste-rious turf diseases and bugs, and mostknow they should generally fear termslike Poa annua, goosegrass, andbrown patch. But for the averagegolfer the pest most feared is theaerifier. And while superintendentsspend many hours studying the agro-nomics of maintaining greens, they areoccasionally guilty of putting the needsof the turf over those of the golfer. Thebest superintendents recognize theneed to seek a middle ground - to

establish a level of maintenance thatresults in a healthy stand of turf butstill provides good putting quality.Obviously, the establishment of thismiddle ground should be the golfer'sgoal as well, since this is their besthope of playing greens that performwell day after day. Finding the middleground is the purpose of this article.

Greens usually do not perform wellor poorly because of a single factor.Instead, like most things, overall per-formance is the result of many influ-ences. To identify these factors, it issuggested a Report Card be developedfor each green. This Report Card will

MARCH/APRIL 1998 1

graphically illustrate where improve-ment is needed.

Quite simply, the Report Card is atool to help golfer and superintendentalike evaluate the many factors thatinfluence the overall performance ofeach green on their course. After thefactors are identified and quantified,steps should be taken to improve eachfactor as much as possible. It probablywill not be possible to bring each factor(or perhaps even any factor) up to agrade of ''A.'' For example, on old orpoorly built greens the factor for in-ternal drainage may be graded as a"D." Through an aggressive aerificationprogram the grade may be raised to"C," but only complete reconstructionwould achieve the "/\' rating. However,it may be possible to raise the grades forother factors as well. Perhaps entranceand exit points can be improved byrerouting a cart path or making greateruse of ropes and signs. Air movementmay be improved by removing brushor trees that block the wind. The re-location of misplaced sprinklers couldimprove the accuracy of irrigation. Theoverall impact of raising three or fourfactors will be a significant reductionin the influence of a factor that can-not be altered. In other words, theoverall performance of the green canbe expressed as a simple formula: TheAverage of Factors A + B + C + D +E ... = Overall Green Performance.

Think of each green as a decathloncompetitor. An athlete whose heightmay limit his or her ability to high jumpwill have to make up points on the200-meter dash to remain competitive.There is another formula you shouldkeep in mind regarding the changesthat are made to improve the greens.This is a case where 1 + 1 + 1 +1 + 1 canactually add up to 6. In other words,by implementing multiple changes(each red ueing the stress on the green),a synergism is likely to occur, reducingoverall stress by more than the sum ofthe individual steps. This is due to thefact that so many of the stress factorsare closely related. Improving one fac-tor frequently results in improvementin one or more of the others.

To be the most useful and effective,the Report Card must be developedwith the combined input of the golfcourse superintendent, course profes-sional, and members of the courseleadership (often the Green Commit-tee). This group is referred to belowas the Rating Team. There are threesteps to completing this evaluationprocess.

2 USGA GREEN SECTION RECORD

Step 1Assign an overall performance

grade to each green. Before headingout to the course, the Report Cardrating team should first gather in acomfortable and private area to discusswhat lies ahead. This is also the timeto complete the first phase of theReport Card - assigning a letter gradeto each green's overall performance.Just like in school, a grade of "/\' re-flects superior performance, and "F"indicates failure. This overall grade ismuch like a college student's final GPA

Layers in the green profile severelyrestrict internal drainage and can evenblock it altogether. Conventional aerifi-cation may not be deep enough to fullypenetrate a buried layer. Deep-tineaerification is the next step in solvingthe problem.

or grade point average over four yearsof education. Be sure not to base theoverall grade on a single good or badseason. Base the grade on four or fiveyears' worth of performance.

Step 2Visit each green to complete the

Report Card and identify wherechanges should be made. This iswhere the evaluation process gets moredetailed. Listed on the accompanyingrating sheet are many factors, each ofwhich should be assigned a letter grade.Notice that the sheet has room to addadditional factors. It also is possible

that some of the factors listed are notapplicable to your particular course.Since the grades are obviously subjec-tive, it is important that the entire ratingteam participate in the evaluationprocess from start to finish. It is alsoadvisable to complete the process in asingle day. Based on personal experi-ence with this rating concept, 18greensshould take approximately three hoursto rate fairly.

Step 3Implement the changes. The Report

Card is useless unless changes aremade to improve the overall growingconditions on the greens. Implement asmany positive changes as possible,keeping in mind that no single changewill have the impact of multiplechanges.

Factors Influencinga Green's Performance

Listed below are the factors that havethe greatest impact on the overall per-formance of a green. (Note that they arenot listed in any particular order.) Alsoincluded are some criteria for deter-mining a grade for each factor. It shouldbe viewed as a starting point and not aninflexible guide that must be followedto the letter. Your rating team probablywill find it helpful to modify the criteriato better fit your course.

LightA basic agronomic fact that is over-

looked far too often is that turfgrassrequires light (lots of it) to flourish. Asyou rate each green for light, keep inmind what you probably learned backin the fourth grade. Light is necessaryfor photosynthesis. Photosynthesis isthe process of turning the energy oflight into energy the plant can use forgrowth. Growth is necessary for a plantto withstand and recover from wearand tear. Therefore, it stands to reasonthat when less light is available, the turf-grass is less able to withstand traffic.

The steps to improve the grade forlight are obvious. Tree pruning, and insome cases complete removal, will benecessary to provide better growingconditions. It is easy to forget that treesgrow larger every year and as a resultblock more light each season. Keepthis physiological fact in mind whensomeone observes, "We never used tohave problems with that green."

• "/\' - given to greens that receive8 hours or more of direct sunlight.

• "B" - given to greens that receive6 to 8 hours of direct sunlight.

Often, something as simple as eliminating triplex mowing in favor of walk-behind canbe enough to help a green through the rough times.

• "C" - given to greens that receive4 to 6 hours of direct sunlight.

• "D" - given to greens that receive2 to 4 hours of direct sunlight.

• "F" - given to greens receiving lessthan 2 hours of direct sunlight.

Air MovementAir movement across the putting

surface has a very strong influence onthe overall health of the turf - par-ticularly in terms of disease suscepti-bility and cooling of the plant. Thepathogens responsible for the mostdevastating turfgrass diseases are farless active (and therefore less destruc-tive) when air moves immediately overthe turf. The air movement helps keepthe turf and the surface of the soil dry.Wet,. stagnant air provides excellentconditions for pathogens to proliferate.From a cooling standpoint, a goodcomparison can be made to our built-in air-conditioning system - perspira-tion. On a hot day, our skin is cooledas we perspire. The plant's perspirationsystem is called evapotranspiration (acombination of evaporation and thetranspiration of water through thestomata or pores of the leaf). Air move-ment must be given high priority for allgreens - particularly on golf courseslocated in climates that include highheat and humidity.

Steps to improve air movement in-clude pruning and possibly removingtrees and brush on the upwind anddownwind sides of the green. Whentree removal is considered to be im-possible because of architectural orsentimental reasons, institute an effec-tive pruning program. Even highmounding around a green can block airmovement, so regrading the moundscan produce a significant improvement.In severe cases, fans are used to providean artificial source of air movement.

• "N' - given to greens that receiveunrestricted air movement across theturf surface.

• "B" - given to greens that areblocked from the predominant windsbut open on other sides.

• "C" - given to greens that wouldreceive very limited air movementwithout the use of fans.

• "D" - given to greens "open" ononly one side.

• "F" - given to greens located inlow areas that receive extremely limitedair movement from any side.

Entrance and Exit PointsCodes for buildings call for a specific

number of entrances and exits based on

the capacity of the building. Perhapsgreens should be given the same con-sideration. When the architecture of agreensite is such that entrance andexit points are severely limited, even asmall annual number of rounds can bequite destructive to the turf. Greensidemounding, bunkering, trees, and otherfeatures can be as restrictive as cattlechutes. Predictably, such restrictionsare far more important on heavilyplayed courses than on the extremelyprivate facility.

Steps for improvement include re-routing cart paths to encourage playersto enter and exit from different sidesof the green. Ropes and signs oftenare necessary evils (but be sure tomove them frequently and keep themin good condition). In severe cases,bunkers may have to be removed orredesigned to provide greater access tothe green. Mounding may have to besoftened, since players instinctivelyavoid walking over hills to get to thegreen. Inconsiderate players mightignore all these efforts to spread trafficout over a large area. However, themajority of golfers realize they benefitthe most from a course in good con-dition and will cooperate with properlyplaced and maintained traffic controldevices.

• "N' - given to a green that has atleast four readily usable entrance andexit points.

• "B" - given to a green that hasthree readily usable entrance and exitpoints.

• "C" - given to a green that hasonly two readily usable entrance andexit points. Other access points existbut will require extensive roping and/orsignage to force players to use them.

• "D" - given to a green with onlyone readily usable entrance and exitpoint. Other access points may exist butrequire extensive roping and/or signageto force players to use them.

• "F" - given to a green with onlyone readily usable entrance and exitpoint and no other real options, regard-less of roping, etc.

Size of GreenGolf has enjoyed tremendous growth

over the past couple of decades. As aresult, the greens on many courses mustendure countless additional rounds. Inmany instances, the original architec-tural design that was appropriate in theearly days of the course simply cannotsupport the twofold or even threefoldincrease in annual rounds that is notuncommon today. Just as many familiesstart out driving a two-seater, thesefamilies often find themselves drivingstation wagons ten years later.

Steps for improvement are limited.Since greens sometimes grow smallerover time (as the workers on themowers try to avoid scalping theedges), it is possible that the originalboundaries of the green can be reestab-lished, providing additional squarefootage. A probe should be used tofind the original edge of the rootzone

MARCH/APRIL 1998 3

Triplex mowers on sharp turns can result in severely worn turf. Simply changing towalk-behind mowers may be enough to return the turf to good health.

cavity. It should be noted that even ifthe green has grown it, enlarging thesurface may take a lot of effort. Forexample, in areas of the country wherebermudagrass fairways and banks sur-round bentgrass greens, simply enlarg-ing the mowing pattern would likelyintroduce bermudagrass into the bent-grass green. In this situation, fumiga-tion of the bermudagrass in the areato be recovered as green should beaccomplished first.• 'w' - given to a green in excess of

7,000 square feet.• "B" - given to a green 6,000 to

7,000 square feet in size.

• "C" - given to a green 5,000 to6,000 square feet in size.

• "D" - given to a green 4,000 to5,000 square feet in size.

• "F" - given to a green less than4,000 square feet in size.

Cupping AreaAnother factor that has been strongly

impacted by the increase in the popu-larity of the game (and therefore in-creased traffic on the greens) is cuppingarea, or the number of areas in whichthe hole can be fairly located. As ageneral rule, the hole should be locatedapproximately five paces from the edgeof the green, and the putting surfacewithin three feet of the hole should beon the same plane.

Estimating the percentage of thegreen that is usable for hole locationstakes a little practice. To develop a feelfor this estimating process, try the fol-lowing procedure on the first couple of

4 USGA GREEN SECTION RECORD

greens rated. Using tees, roughly out-line the portions of the green in whichthe hole can be reasonably placed.Next, estimate the square footage ofeach marked area. Add the squarefootage together and divide the sum bythe total square footage of the green.For example, suppose there are threeareas of the green that can be used forhole locations. The total square footageof these three areas is approximately1,500 square feet. The entire greenmeasures 6,000 square feet. 1,500 +6,000 = .25 or 25%.

Steps to increase cupping area in-clude the restoring of original green

boundaries (as discussed above in the"Size of Green" section) and selectinga speed for the greens that is appropri-ate to their contouring. For example,a green mowed at 18of an inch androlling 9 feet on the Stimpmeter mayyield a rating of "D." Raising the cut toY3z inch might yield a speed of 8 feetand increase the percentage of usablecupping area to a "C" or even "B"rating.

Assuming greens are moderatelysized to begin with, use the followinggrades to rate cupping area:• 'w' - given to greens with cupping

areas in excess of 50%.• "B" - given to greens with cupping

areas between 40% and 50%.• "C" - given to greens with cupping

areas between 30% and 40%.• "D" - given to greens with cupping

areas between 20% and 40%.• "F" - given to greens with less than

20% cupping area.

Surface DrainageSurface drainage is extremely impor-

tant to every green, including thosewith good internal drainage. Even thebest-constructed rootzone will gradu-ally drain more slowly.This is due to theproduction of organic matter by theplant and the introduction of soil fines(notably clay, silt, and very fine sand)into the rootzone over the years. Thesefines are introduced through topdress-ing, wind, and even during irrigationwhen the water supply contains sus-pended solids. It is even possible forsome types of sand to be chemicallyweathered, causing a reduction in size.

Without good surface drainage, watercollects in the low areas of the green,resulting in extremely poor growingconditions for the turf. The rootzonebecomes saturated and can remainthat way for extended periods of time.This results in anaerobic (withoutoxygen) conditions, which can lead tothe death of the plant. Disease inci-dence also increases, as does the occur-rence of algae and soured soil (oftenreferred to as black layer).

Surface drainage occasionally can beimproved by lifting the sod, addingadditional rootzone mix to eliminatethe water-collecting hollow, and re-placing the sod. Obviously, this step ispractical only in small areas and nearthe edges of the green. Sometimes sur-face drainage is blocked by the devel-opment of thick thatch in the turfimmediately adjacent to the green. Re-moval of the sod and thatch, followedby replacement with a thatch-free sod,may be all that is necessary to allowwater to once again flow off the green.• 'w' - given to greens with no water

collecting hollows and surface drainagein at least three directions.

• "B" - given to greens with nowater collecting hollows and surfacedrainage in two directions.

• "C" - given to greens with nowater collecting hollows and surfacedrainage in one direction.

• "D" - given to greens with surfacedrainage to the center of the green andone surface exit point.

• "F" - given to greens with watercollecting hollows.

Internal Drainage andRootzone Porosity

Internal drainage and rootzoneporosity are often the only factorsconsidered when determining theneed for the complete reconstructionof golf greens. The USGA providesspecific guidelines regarding these fac-

Good air movement across the putting surface is vital for disease suppression andplant cooling. If tree pruning or removal is not possible, fans are the next best option.

tors (see the USGA's Guidelines tora Method at Green Construction).However, all too often greens will berebuilt to meet these guidelines withoutconsideration of the many other factorsthat contributed to the poor perfor-mance of the original green. Not sur-prisingly, in many instances the newgreen does not perform as well as ex-pected. Internal drainage and porosityare extremely important, but theycannot compensate for the lack oflight, poor air movement, poor trafficcontrol, etc.

Good internal drainage is withoutquestion very influential to the overallperformance of the green - particu-larly in adverse climates and in areaswhere water quality is less than ideal.The degree of internal drainage is mea-sured as saturated hydraulic conduc-tivity. Rootzone porosity representsthe sum of two types of porosity -capillary and non-capillary. Capillaryporosity is a measure of the percentageof pores in a rootzone mixture that arefilled with water at field capacity, whilenon-capillary porosity refers to thepercentage of pores filled with air. Todetermine these factors accurately,samples should be removed from thegreen and submitted to an accreditedphysical soil testing laboratory.

Short of complete reconstruction,the most effective means of improvinginternal drainage and porosity is toincrease aerification. Often, a combi-nation of deep-tine and conventionalcore aerification is necessary. Manycourses now include water-ject aerifi-cation as a supplement to the mechan-ical aerification practices.

• "N.' - given to greens built inaccordance with USGA guidelines.

• "B" - given to non-USGA greenswith hydraulic conductivity rates over3 inches per hour and a functionalsubsurface drainage system.

• "C" - given to greens with hy-draulic conductivity rates over 3 inchesper hour but no subsurface drainagesystem.

• "D" - given to greens with hydrau-lic conductivity rates of 1 to 3 inchesper hour.

• "F" - given to greens with hydrau-lic conductivity rates of less than 1inch per hour.

Irrigation Control and CoverageThis is another area that frequently is

overlooked when evaluating the over-all performance of greens. Althoughproper irrigation has always been im-portant, the lowering of cutting heights

and the use of different grass speciesin the vicinity of the greens has en-hanced the need for as much controland accuracy as possible. Commonsense should make us wonder howfull-circle, overhead sprinklers thatcover the green, surrounds, and fairwayapproach areas, can possibly meet thespecific needs of the turf in each area.For example, a bentgrass or bermuda-grass green maintained at 116 inch orless does not conveniently have thesame water requirements as the ber-mudagrass fairway cut at ~ inch or thebluegrass rough mowed at 2 inches.Different cutting heights and differentturfgrasses demand different irrigationfrequencies and volumes. As a result,even a well-designed and properly in-stalled and operated system often mustbe supplemented with hand watering.And, obviously, a system with poorspacing, improper nozzles, or improperpressure adjustments will cause noth-ing but problems.

Steps for improvement include up-grading the irrigation system to providesingle head control, installing a perim-

eter system to water the surroundingturf separately from the greens, relocat-ing heads to provide even coverage,and altering nozzle sizes to achievebetter coverage and proper pressureregulation. Hand watering can also beincreased to help compensate for asubstandard irrigation system.

• ''1\' - given to greens irrigated witha combination of full-circle and adjust-able part-circle heads facing outward.Such a system is often referred to as aperimeter system. Each of the headsshould be able to be controlled inde-pendently through the automatic irri-gation system.

• "B" - given to greens without aperimeter irrigation system but withsingle head control of sprinklers thatare correctly spaced.

• "C" - given to greens without aperimeter irrigation system and withoutsingle head control.

• "D" - given to greens with noperimeter system, no single head con-trol, and the satellite that controls thegreens is located on the same irrigationcycle as other areas of the course.

MARCH/APRIL 1998 5

Good employee tenure usually results in a better-trained crew. Knowing the difference between cooling the turf and spot watering,and when each technique is needed, can result in better-managed turf during stress periods.

• "F" - given to greens with amanual irrigation system.

Purity of Turf StandOlder greens are often composed of

more than one species of turfgrass andeven various biotypes of the samegrass. For example, older bentgrassgreens often have large percentages ofPoa annua intermixed with the bent.Biotypes of both bentgrass and ber-mudagrass in greens begin to segregateover time, resulting in many patches ofdistinctly different grasses in the samegreen. Each of these different grassesand biotypes has a particular set of vul-nerabilities to insects, disease, climaticstresses, and, particularly, cuttingheights. As a result, the more varied themakeup of the putting surface, themore difficult it is to manage.

With the exception of very minoroutbreaks of Poa annua and/or off-type grasses, there is little that can bedone to restore the purity of the standof grass other than completely replant.Until then, raising cutting heights tosuit the type of grass in the green thatis least able to tolerate low cuttingheights will help provide uniformity interms of putting quality.

• "Pt - given to greens composed ofa pure stand of turf.

• "B" - given to greens with lessthan 20% "off" types.

• "C" - given to greens with lessthan 30% "off" types.

• "D" - given to greens with lessthan 40% "off" types.

6 USGA GREEN SECTION RECORD

• "F" - given to greens with less than50% "off" types.

Amount of PlayNo agronomic mysteries here - the

less you use your greens, the healthierthe turf will be. When golfers maketheir inevitable comparisons from onecourse to the next, the amount of traf-fic the greens must endure often is themost overlooked factor.

To deal effectively with traffic, it isvital the greens be established to thebest turf for the climate in which thecourse is maintained. What is agro-nomically possible does not mean itis agronomically sensible. Bentgrassgreens maintained in hot and humidclimates cannot tolerate the sameamount of playas bermudagrass greensin the same climate. The superinten-dent also should be sure that ade-quately high cutting heights are main-tained to cushion the turf from heavytraffic loads. Topdressing, fertilizing,and grooming practices must be ad-justed to maintain a pad or thin layer oforganic matter between the crown ofthe plant and the underlying (usuallyabrasive) rootzone mixture. Potassiumlevels should be kept at recommendedlevels to provide a stronger plant that isbetter able to withstand stress. Spike-less shoes should be encouraged toreduce injury to the turf.• 'W' - given to greens that receive

fewer than 20,000 rounds per year.• "B" - given to greens that receive

fewer than 30,000 rounds per year.

• "C" - given to greens that receivefewer than 40,000 rounds per year.

• "D" - given to greens that receivefewer than 50,000 rounds per year.

• "F" - given to greens that receivemore than 50,000 rounds per year.

Water QualityThe water used to irrigate the greens

can make the difference between suc-cess and failure of the turf. Greensmaintained with water high in salts orbicarbonates are predisposed to a widevariety of problems. Establishing agrade system for water quality is im-possible, since so many factors inter-act. If you have questionable waterquality, it is best to solicit the input ofa qualified agronomist to determinethe impact of the water on the turf, aswell as steps for improvement. Theratings listed below are therefore highlygeneralized.• 'W' - excellent water quality.• "B" - good water quality.• "C" - marginally acceptable water

quality.• "D" - poor water quality.• "F" - very poor water quality.

Other Rating FactorsThere are many other factors that

may need to be considered by the rat-ing team. These could include thefollowing:

• Nematode levels.• Experience and skill of mainte-

nance crew.• Availability of proper maintenance

equipment.

• Tenure and skill of the super-intendent.

• Tree root competition.• Cutting height.Rating the skill of the superintendent

is perhaps the most subjective processof all. Without question, a skilled super-intendent who has been given time tolearn the nuances of a particular set ofgreens can have a very positive impacton the overall performance of thosegreens. However, no superintendent,regardless of skill, can completely over-come stresses resulting from the manyfactors discussed earlier. The superin-tendent cannot independently providelight, air movement, adequate size,drainage, or good water quality. Assum-

ing your course has a superintendent ofat least average ability, the team wouldbe wise first to correct the many otherfactors that are holding back the greens.It is amazing how often a superinten-dent considered by the golfers to bewithout talent suddenly develops agreen thumb when given the oppor-tunity to manage properly constructedgreens. By the way, there are steps totake to help the superintendent im-prove as well. The leadership of thecourse should support the superinten-dent's efforts to learn by providing theopportunity to attend educational ses-sions on national, state, and locallevels. The science and art of greensmanagement changes rapidly with theintroduction of new technologies and

the ever-increasing stresses today'sgreens must endure.

ConclusionDeveloping the Report Card can

identify where work is needed to im-prove the greens. It can also help deter-mine whether or not reconstruction isnecessary. Finally, completing the Re-port Card before building or rebuildinggreens can help ensure that, when theconstruction is finished, the greens willbe both agronomically sound and ca-pable of providing top-quality puttingconditions.

JAMES FRANCIS MOORE is Director ofthe USGA Green Section's ConstructionEducation Program.

Table 1Report Card for Date Completed

FACTOR 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18Light

Air movement

Entrance and exit points

Size of green

Cupping area

Surface drainage

Internal drainage

Irrigation control/coverage

Purity of turf stand

Amount of play

Water quality

Historical Performance

MARCH/APRIL 1998 7