Putting an End to Those Fried-Egg Liesby JAMES T. SNOWDirector, Northeastern Region, USGA Green Section

THE SAND IS TOO SOFT! Thisis a common response to theplayability of sand bunkers

where old, contaminated sand hasrecently been replaced with severalinches of fresh material. Sometimes thecriticism is justified; sometimes it is not.Consider the following scenario:

After many years of putting off theinevitable, Tired Trap Country Clubfinally decides to renovate its bunkers.The old sand, which has graduallybecome contaminated with soil andorganic debris, has lost its original color

and consistency and has become toohard. Because of its poor color andhardness, some golfers insist that thereis no sand at all in some of the bunkers.In the process of renovation, the oldmaterial is replaced with 4 to 6 inchesof fresh, new sand, as recommended bythe USGA. Before the first day is done,golfers begin complaining that the newsand is much too soft and is unsuitablefor their course.

More often than not, the sand thathas been added to bunkers in suchinstances is perfectly good. The reaction

of the golfers, though, is predictable andunderstandable. Having played fromfirm, contaminated sand for manyyears, playing from the new, unsettledsand is a striking change. The fresh sandwould indeed seem soft by comparison.

Golfers should be advised that whenthis type of renovation work occurs, thenew sand takes time to settle and willvery likely seem soft for several months.During this time, the sand will developa greater firmness and the golfers willbecome accustomed to playing from asofter base. Generally, the number of

Wetting the sand and packing it with a utility vehicle is one good wayto firm newly installed material.

(Opposite page, top) One way to test different sands prior to a sand bunker renovation program.(Opposite page, bOllom) A cement finisher can be used to quickly firm soft sand.(Above) Hand raking smoothes the surface without loosening the sand.

complaints diminishes once the newsand has been in place for several weeks.

Another complicating factor isgolfers' preferences for; different typesof bunker sands. Some prefer firmsands, while others like softer sands.

On the other hand, it is possible thatthe new sand is indeed too soft. Underthese circumstances it could take yearsof contamination with soil and organicdebris before a good firmness develops,during which time golfers would besubjected to poor playing conditionsand fried-egg lies.

The difference between a good-quality sand that is temporarily softafter installation and a sand that will betoo soft for months or years to come is

not easy to detect, especially from avisual standpoint. The best way to avoida sand that is too soft is to do yourhomework. Contact clubs in your areafor recommendations, and talk to theirgolf course superintendents, golf pro-fessionals, and other club members forcomments. Play their courses if you can,especially if their sand has recently beeninstalled.

If locally used sands are unsuitablefor play or from a budget standpoint,then a search must be made of localquarries for a satisfactory sand. Contactthe regional office of the USGA GreenSection in your area for guidelines inselecting bunker sands, and use theparticle size range, particle shape, andchemical composition parameters from

the guidelines to help sort out thepotentially useful sands.

IF THERE is any doubt about yourchoice, send samples of the best-

looking sands to a soils laboratory thatis experienced in evaluating sands forbunker use. The lab should be able toprovide a description of the playabilityof each sand and discuss any potentialproblems, allowing the choice to be nar-rowed down to one or several selections.If doubts remain, install different

sands in a limited number of bunkers onthe course or in several test bunkers forfurther evaluation. After a few monthsor a season of use, the best sand shouldbe apparent.

Having to take all of these steps tofind a suitable, affordable bunker sand

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is not common, but many courses paya high price for not taking the time tofully investigate and test the sand theyare placing in their bunkers. Many acourse has gone through the disruptionand expense of replacing old bunkersand, only to go through the wholeprocess again within a year or twobecause the members were unhappywith the material.

When a sand already has been in-stalled in a bunker and is found

to be too soft, there are a number of dif-ferent steps that can be taken to correctthe problem. If the sand is extremelysoft and fried-egg lies are common, senda sample to a good soil-testing labora-tory for evaluation. If the lab suggeststhat the sand will be a problem for sometime to come, it might recommend adifferent sand, with a distinctly differentparticle size range, be mixed with theexisting sand to give it greater stability.For best results, the existing materialsshould be removed from the bunker andmixed off-site with the new sand. Thisprocedure would be feasible with onlya bunker or two involved, but on-sitemixing would be the only practicalalternative if the sand in all or many ofthe bunkers had to be modified.

Before an expensive sand replace-ment or modification procedure is insti-tuted, though, there are a number ofrelatively simple practices for firmingsoft sand that should be tried. Forexample, if the depth of the sand in thebunker is 6 inches or more, then reduceit to about 4 inches in the flat areas and2 to 3 inches on the faces. Since thedegree of fluffiness of the sand isdirectly related to its depth, removingsome of the excess sand should mini-mize the potential for fried-egg lies.When sand depth is at a 4-inch level,though, it is often difficult to use amechanical rake without digging intothe soil in the base of the bunker. Thismethod of firming sand, then, requirescareful use of the mechanical rake,modifications to the rake to reduceits cultivating activity, or more handraking.

Another good approach to firmingsoft sand is to try to pack the particlescloser together. Some sands pack moretightly than others. Sometimes, irri-gating the sand is all that is necessaryto adequately reduce its fluffiness. Abetter method is to wet the sandthoroughly and run back and forthmany times across the surface with atractor, a riding mechanical rake with

the cultivator bar removed, or a utilityvehicle of some type.

An excellent compaction techniquefor firming sands involves the use of acement finisher (a steel plate mountedto a gasoline-powered engine that pro-duces a compacting effect by vibratinghorizontally). After the sand has beenthoroughly watered, the machine isused to compact the sand to the desiredfirmness. The compactor can be rentedby the day from most rental outlets, orit can be purchased for less than $1,500if a large-scale sand-replacement pro-gram is anticipated. For more infor-mation, see "A Technique For DealingWith Soft Sand" in the March/April 1989issue of the GREENSECTIONRECORD.

As noted earlier, irrigation is a goodmethod for temporarily firming a softsand. Ironically, sands that are rakedwhen they are wet tend to be especiallyfluffy as they dry out. Because of thesurface tension of water, wet sandparticles tend to bridge more readilywhen they are cultivated and thereforedevelop a looser texture. As dryingoccurs, the structure of the sandremains intact until it is subjected totraffic. This is quite a common effect,since irrigation is often done during thenight, and sand bunkers are usuallyraked during the early morning hours.

Removing the cultivation bar and adding lead weights to the smoothing apparatus isone way to modify the mechanical rake for accommodating soft sand.

4 USGA GREEN SECTION RECORD

To PARTIALLY overcome the soft-sand problem that occurs when wet

sand particles are raked, many coursesregularly use wetting agents in theirbunkers. Since the wetting agent re-duces the surface tension of water, thebridging effect is reduced and the sandis better able to retain its firmness aftercultivation. To be effective, the wettingagent must be used regularly, as oftenas once per week during periods offrequent irrigation or rainfall andregular cultivation. Only light rates ofwetting agents need be applied, andnearly any product is satisfactory forthis use as long as it is non-phytotoxic.This practice is most likely feasiblewhen just a few bunkers are involved.Other means of firming sands should beconsidered when dealing with a largenumber of bunkers.

In trying to develop greater firmnessin a naturally soft sand, two generalstrategies must be adopted. The firstinvolves filling more of the pore spacebetween the sand particles by way ofcompaction techniques or by addingsand particles of a different size. Thishas been the theme of the practicesmentioned in the discussion thus far.

Moving sand from where it is too deep to where it is too shallow.

The second strategy consists of sub-jecting the sand to as little cultivationas possible. This makes sense, becausecultivation is a loosening process thatwould only make a soft sand softer.Unfortunately, raking is an integral partof sand bunker maintenance, serving tokeep the surface smooth and to keepweeds in check. A compromise must bereached, then, to serve these opposingneeds.

A typical sand-raking program atmany courses involves the use of ariding mechanical sand rake as little asonce or twice per week to as often asonce per day. The rake usually isequipped with teeth or a bar thatcultivates to a depth of several inches.What's more, the operator usually makesnumerous passes around a bunker to doa thorough job of smoothing and culti-vating every square inch of sand.

Given the frequency and depth towhich bunker sand is raked, it is notsurprising that there are so manycomplaints about fried-egg lies in newlyinstalled sands. If the objective is tomaintain greater sand firmness, then itis clear that cultivation depth andfrequency should be reduced. There-fore, instead of raking the bunkers sixor seven days per week, reduce it to onceor twice per week, if possible. On dayswhen the mechanical rake is not used,touch up footprints and other irregu-

'" larities with hand rakes.

ANOTHER OPTION is to modify the~mechanical rake so that it smoothsthe surface without doing much culti-vation or loosening of the sand. Culti-vating teeth can be shortened, or thecultivating bar can be raised or re-moved, for example. Golf course super-intendents have come up with all kindsof homemade accessories for themechanical rake which work very wellfor smoothing sand while doing aminimal amount of cultivation. Fromtime to time the cultivating bar can betemporarily reinstalled on the machineto control developing weeds in thebunkers.

Regular use of the mechanical rakecauses other sand softness problems aswell. When used frequently and at fastspeeds, the rake can redistribute thesand throughout the bunker and causea wide variation in sand depth. It is notuncommon to find 8 to 10 inches of sandin some areas and only 2 to 3 inches inother locations. Naturally, softnessproblems are more prevalent in areaswhere the sand is deeper. Sand depth,

therefore, should be closely monitoredin bunkers where the mechanical rakeis often used.

As noted before, many courses arereducing their use of the mechanicalrake and relying more and more onhand raking. The misuse of themechanical rake is a key factor withrespect to keeping soft sands soft,hastening the contamination of goodsands with soil and other debris, andcausing the deterioration of bunkeredges and lips. Indeed, hand raking isan excellent means of keeping soft sandfirmer while keeping the surface of thesand smooth and playable. Many stylesof rakes are for sale, and some are verywell suited for this purpose. Some haveshort, stubby, cultivating teeth, whileothers have none at all. Hand rakingprograms require more labor time, butmany courses find that the improve-ment in playability and the red uced rateof sand and bunker edge deteriorationare important compensating factors.

Most of the options for dealing withfluffy bunker sands are temporary mea-sures. They are usually quite adequate,though, because all bunker sands aresubject to soil and organic mattercontamination that makes them firmerover a period of time. Silt and clayparticles from the base of the bunker

and from its edges eventually becomeintermixed with the sand to fill porespaces and bind the sand. Soil, dust, andorganic debris also find their way to thebunkers by way of wind, mowing andedging practices, or other means. Astime goes by, then, the problemsencountered with soft sands and fried-egg lies gradually disappear.

Whether or not to use geotextileliners in sand bunkers is an arguablepoint. It is a factor, though, in a bunkerrenovation program where a soft sandis being used. Because a liner can, withluck, remain in place for a number ofyears and greatly reduce the rate of soilcontamination from important sources(i.e., the base and edges of the bunker),it can substantially increase the amountof time it takes for a very soft sand tobecome firmer. Where the use of linersis being considered, therefore, it is evenmore important to test the sand that willbe used to be sure that it is not too soft.

Sand bunkers are important and ex-pensive features on many golf courses,and they are a source of criticism formany golf course superintendents andclub officials. Complaints about softsand and fried-egg lies, however, neednot occur if reasonable caution is takenin selecting, installing, and managingbunker sands.

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