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One way to avoid overwatering is to have two sets of sprinklers in order to irrigate the green separately from the surrounding rough. Putting Green Drainage, Drainage, Drainage Just as location is important in real estate, drainage is the foundation of any good putting green. BY JAMES H. BAIRD rainage has long been considered the single most important element of good quality putting greens, and more often than not, failure of putting green turf can be traced back to one or more factors related to excess moisture and the inability to get rid of it. Poor drainage creates softer conditions on putting greens, exacerbating ball marks, footprints, spike marks, and wear damage, especially around golf holes, all of which adversely affect ball roll and the ability to make a putt. Wet soil is more prone to compaction, which leads to weak, shallow- rooted turf and encroachment of algae, moss, and Poa al'll'lua. In the end, turf in poorly drained areas usually succumbs to diseases such as anthracnose or Pythium, or stress caused by traffic, mower scalping, or weather extremes. In northern climates, loss of turf from winter injury frequently occurs in poorly drained areas of putting greens. Troubleshooting a drainage challenge is likely to start by examining the underlying soil. How- ever, soil is just one of several factors that can contribute to wet greens. The objectives of this article are to outline the various causes of poor drainage in putting greens and to offer the best and most current solutions. STEPONE: LOOK AROUND Before reaching for your soil probe, take a step back and look around the green. Pay particular attention to irrigation, trees, traffic patterns, side- hill seepage or runoff, and poor surface drainage. IRRIGATION Overwatering due to improper irrigation prac- tices, poor irrigation design, or both, is one of the leading pitfalls of golf turf maintenance and can contribute to poor drainage. Unfortunately, some 16 GREEN SECTION RECORD

Putting Green Drainage, Drainage, Drainage

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Page 1: Putting Green Drainage, Drainage, Drainage

One way to avoidoverwatering is tohave two sets ofsprinklers in orderto irrigate the greenseparately from thesurrounding rough.

Putting Green Drainage,Drainage, DrainageJust as location is important in real estate, drainageis the foundation of any good putting green.BY JAMES H. BAIRD

rainage has long been considered thesingle most important element of good

quality putting greens, and more oftenthan not, failure of putting green turf can betraced back to one or more factors related toexcess moisture and the inability to get rid of it.Poor drainage creates softer conditions on puttinggreens, exacerbating ball marks, footprints, spikemarks, and wear damage, especially around golfholes, all of which adversely affect ball roll andthe ability to make a putt. Wet soil is more proneto compaction, which leads to weak, shallow-rooted turf and encroachment of algae, moss, andPoa al'll'lua. In the end, turf in poorly drained areasusually succumbs to diseases such as anthracnoseor Pythium, or stress caused by traffic, mowerscalping, or weather extremes. In northernclimates, loss of turf from winter injury frequentlyoccurs in poorly drained areas of putting greens.

Troubleshooting a drainage challenge is likelyto start by examining the underlying soil. How-ever, soil is just one of several factors that cancontribute to wet greens. The objectives of thisarticle are to outline the various causes of poordrainage in putting greens and to offer the bestand most current solutions.

STEPONE: LOOK AROUNDBefore reaching for your soil probe, take a stepback and look around the green. Pay particularattention to irrigation, trees, traffic patterns, side-hill seepage or runoff, and poor surface drainage.

IRRIGATIONOverwatering due to improper irrigation prac-tices, poor irrigation design, or both, is one of theleading pitfalls of golf turf maintenance and cancontribute to poor drainage. Unfortunately, some

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Page 2: Putting Green Drainage, Drainage, Drainage

turf managers find it easier and safer to err onthe side of applying too much water rather thanbarely enough, especially since most golfers viewlush, green turf as good and anything less asproblematic.

Besides reminding golfers that" green is notnecessarily great," putting green irrigation systemsof today should include properly spaced sprinklersthat provide uniform water distribution andare controlled individually for site-specificwater management. In addition, a second set ofsprinklers should be installed to irrigate the greensurrounds separately from the putting surface toaccount for differences in water use requirementsrelative to mowing height and turf grass species.Irrigation scheduling should be based upon acombination of weather data and frequentmonitoring of soil moisture to prevent excessirrigation. Finally, having a state-of-the-artirrigation system and employing proper irrigationscheduling methods will significantly reduce butnot eliminate the need to hand water.

TREESTrees contribute to poor drainage by blockingsunlight and air circulation, which reduces bothevaporation and transpiration of moisture fromthe turf canopy. As a result, irrigation must berestricted accordingly to account for reducedwater loss. Remove trees that block the directionof the prevailing wind and sunlight, especiallyduring the morning hours when photosynthesisis optimal and in order to dry out the turf canopyto reduce disease incidence. If that is not possible,use fans. These will artificially elevate the evapo-transpiration rate and help the turf pull morewater from the soil, thereby aiding in drainage.

TRAFFICWet turf is particularly susceptible to weardamage and soil compaction caused by concen-trated traffic from equipment and golfers. Switch-ing from triplex to walk-behind mowers, andfrom grooved to solid front rollers on the cuttingunits can help reduce turf wear, especially onpoorly drained greens. Removal or repositioningof trees, bunkers, or other obstructions aroundthe green can help to improve traffic distribution.Raising the height of cut is the easiest way toincrease cupping area on sloped greens withouthaving to level, add to, or rebuild putting greens.Finally, increasing cultivation practices such asaeration and sand topdressing will help reducesurface compaction and improve drainage.

SIDE-HILL SEEPAGE OR RUNOFFLook for drainage challenges that may be causedby excess water from neighboring slopes. The bestsolution for side-hill seepage is to install an inter-ceptor or curtain drain just above the wet areanear the base of the slope. The bottom of thetrench should be positioned just into the less-permeable subsoil and then back-filled with stoneor highly permeable sand and drainage pipe.More than one interceptor drain may be neces-sary, depending upon the depth and volume ofwater entering the green.

Repeated applications of the deep drill or tine and sand fillprocedure usually helps to improve wet greens short ofdrainage installation or total reconstruction.

NOVEMBER-D¥CEMBER 2005 17

Page 3: Putting Green Drainage, Drainage, Drainage

SURFACE DRAINAGEThe presence of puddling in low areas of a greenfollowing irrigation or natural precipitation is asign of poor surface drainage. This phenomenoncan be caused by poor design and/or construc-tion, or by settling over time. Poor surface drain-age can be overcome by additional and selectivetopdressing of low areas. Broader low areas mayrequire removal of the sod, regrading of and/oraddition to the underlying soil, followed byreplacement of the sod. Inadvertent topdressingapplications to collars may create a "lip" thatprevents positive surface drainage from the edgeof the green. Extra aeration with core removaland rolling may solve this problem; however, forsevere cases, regrading may be ~ecessary.

In extreme cases, for example on a punch-bowlgreen, it may become necessary to install a surfaceinlet drain at the lowest point in the depression.Although this type of drain can obstruct playa-bility, it will allow a large volume of water toleave the surface and enter the collector pipe. Be

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sure to use a large enough grate and pipe tohandle the surface water and install a trap tocapture sediment or debris before it enters thedrainage system.

STEPTWO: LOOK DOWNAfter looking around, next grab your soil probeor profiling tool to examine the soil profile. Theinitial evaluation can be subjective in nature,looking for clues such as color, hardness, rootdistribution and depth, presence of thatch, or anyother visible layers. The most common causes ofsoil-related poor drainage are layering andimpermeable soil.

LAYERINGLayering can be caused by excessive thatchaccumulation, poor construction methods, incon-sistent use of cultivation practices, including top-dressing materials and the frequency of applica-tion, or continued use of the same cultivation

Page 4: Putting Green Drainage, Drainage, Drainage

Installation of slitdrainage is effective.but it is usuallymore disruptivethan subsurfacedrainage.

practice whereby a "plow-pan" or compactedarea develops underneath the penetration depthof the tine or implement. Most of the time, layer-ing problems can be alleviated by aggressive con-ventional and/or deep-tine aeration combinedwith sand topdressing to maintain the integrity ofthe channels.

IMPERMEABLE SOILOne of the most common causes of poor drain-age is impermeable soil underneath the green.The desire to save a buck or two during con-struction can often lead to use of an improper orpoorly drained rootzone mix. On the other hand,even an ideal rootzone mix can become poorlydrained if cultivation practices such as aeration,verticutting, and topdressing are not performed asneeded to minimize organic matter accumulation.Poor drainage is often associated with greens thatwere constructed using finer-textured native soils.Over time, drainage in these greens usuallyworsens due to organic matter accumulation,

increased play and resultant compaction, andchanges in equipment, irrigation, and othermaintenance practices.

If the drainage problem is not too severe, thenaggressive aeration and sand topdressing will likelyimprove the soil to a point where no furtheraction is needed. In more severe cases, it would bebest to have an accredited soil testing laboratoryconduct a more objective analysis of the soil. Thelaboratory will provide instructions for submittingundisturbed soil proftles from the green(s) inquestion using PVC pipe. A complete physicalanalysis is usually conducted on two or moresections of the profile to determine particle sizedistribution, density, infiltration rate, porosity, andorganic matter content. In most situations, recom-mendations for improving drainage in imperme-able soil will involve either installation of drainageor complete reconstruction of the putting green.The two most common methods of drainageused today in the Northeast are slit drainage andsubsurface drainage.

NOVEMBER-DECEMBER 2005 19

Page 5: Putting Green Drainage, Drainage, Drainage

Subsurface drainageinstallation is tediouswork that is oftenbest left to theexpertise of adrainage contractor.

Slit drainage can be installed using a customizedvibratory plow, which injects coarse sand intoveins that are approximately 1 inch wide, 12inches deep, and on 1- or 2-foot spacing, depend-ing upon subsoil composition, compaction, andsurface pitch of the green. Veins are extendedaway from the green to a low point and thenconnected into a dry well or interceptor drain.Approximately two tons of material are injectedper 1,000 linear feet of drainage installed, equal-ing about 12 tons for a 6,000-square-foot green.The top of the sand is made flush within a halfinch of the putting surface, and then the green isblown, brushed, rolled, and smoothed with top-dressing sand in preparation for play.

There are various procedures for installing sub-surface drainage. The most critical componentsinclude: identification of outlet drain(s); arrange-ment of laterals, depending upon soil characteris-tics and perpendicular to the general slope of thegreen; excavation of narrow trenches by carefulremoval of sod and underlying soil where thedrainage pipe will be placed; installation of 2- or3-inch-diameter perforated drainage pipe sur-rounded by gravel or pea stone; backfilling of thetrench with a rootzone mixture (something onthe order of 60% sand, 20% soil, and 20% peat)using careful tamping along the way to preventsettling; and replacement of the original sodfollowed by more tamping and hand topdressingto smooth out the surface. Use of narrowtrenches and pipe and a "dirty" rootzone mix iscritical to prevent drought stress. Also, pipesshould be extended out of the high end of thegreen cavity and marked with a metal tag so theycan be located and flushed out if necessary.

The decision to install either type of drainagesystem is usually based upon several factors,including size and scope of the drainage problem,timing of the project, and availability of the con-tractor. While subsurface drainage can be installedin-house (see "Wet Greens: Let's Try This First"),the work is tedious and is best left to an experi-enced contractor who can complete the projecton an average-sized green in one day with littleor no disruption of the putting surface. Installa-tion of slit drainage is equally or more rapidcompared to subsurface; however, the puttingsurface will likely not be smooth afterwards, andrepeated aeration and/or topdressing may benecessary to smooth it to an acceptable degree.Longevity is another consideration when choos-ing a drainage method, and it would be logical toassume that wider trenches that contain pipe 'willlast longer than narrower veins of sand. Thenarrow slits may function well initially, but theywill likely become silted in from the surroundingsoil and eventually become non-functional.Nevertheless, the author has observed continuedsuccess of greens with slit drainage more than fiveyears after installation.

FINAL STEP: RECONSTRUCTIONUnfortunately, many courses skip either or bothof the two first steps in identifYing and solvingdrainage problems and go straight to completereconstruction of a green, only to be disappointedlater when poor drainage is not solved and playa-bility is far different from the remainder of thegreens. In the event that all other measures havebeen exhausted and reconstruction is necessary,now is not the time to cut corners in the interestof saving money or time. Working together withyour agronomist and a soil testing laboratory, it ispossible to construct a green that closely matchesthe others in terms of playability without com-promising drainage, drainage, drainage!

REFERENCESCarpenter, L., and D. A. Oatis. 1994.Wet Greens: Let's TryThis First. USGA Green Section Record. 32(4):5-8.Kelly,]., and S.Ami. 2004. Solving Drainage Problems.Greenmaster. 39(3):26-28.McAuliffe, K. W 1992. Drainage Improvement - RemedyWithout Reconstruction in New Zealand. USGA GreenSection Record. 30(2):6-10.Snow,]. T. 1991. Finding Solutions for Poorly DrainedGreens. USGA Green Section Record. 29(1):10-14.

DR.JIM BAIRD is an agronomist in the NortheastRegion if the USGA Green Section.

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