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  • Soi l Nutr i en t Analys i s Laboratory ; 6 Sherman Place , Uni t 5102, Storr s , CT 06269-5102 Phone : 860-486-4274

    Fax: 860-486-4562 Locat ion : Union Cot tage , Depot Campus , Mans f i e ld

    INTERPRETATIONOFSOILTESTRESULTSSoiltestsprovidehomeownersandgrowerswithguidelinesforbothefficientandenvironmentallysounduseoffertilizers,limeandothersoilamendments.RecommendationsarebasedonUniversityresearchandfieldstudies.Ourrecommendations,however,areonlyasgoodasthesampleyoucollect.Samplesshouldberepresentativeoftheareabeingtestedandshouldconsistofamixtureofseveralsubsamplesobtainedthroughoutthesite.Poorsamplingtechniquesmayresultinmisleadingrecommendations.Soiltestresultswilldetectnutrientdeficiencies,excessesorimbalances.Theycannot,however,identifyproblemsduetodisease,insectpests,pesticidesorpoorculturalpractices.SOILPHANDLIMERECOMMENDATIONSSoilpHisameasurementofasoilsacidity.ThepHscalerangesfrom1to14,withapHof7beingneutral.Valuesbelow7areconsideredacidicwhilethoseaboveindicatealkalineconditions.ThepHofasoilnotonlyaffectstheavailabilityofnecessaryplantnutrientsbutalsothesolubilityofpotentiallytoxicelementssuchasaluminumandlead.MostgardenplantspreferapHbetween6.0and6.8.Notableexceptionsincludeacidlovingblueberriesandericaceousplantslikerhododendrons,azaleasandmountainlaurel.TheseplantspreferapHof4.5to5.3.VarietiesofpotatoeswithoutscabresistancearealsogrownatalowerpH(5.2to5.4)toinhibitthegrowthofthisdiseaseorganism.ThemajorityofConnecticutsoilstendtobeacidicwithpHvaluesrangingfrom4.8and5.5duetothegeologyandclimateoftheregion.Groundlimestoneisusuallyrecommendedtocorrectacidsoilconditions.Recommendationsforlimearebasedonthecroporplantsbeinggrown,soilpH,andsoiltextureandorganicmatterestimates.Ingeneral,thelowerthepHandthegreatertheclayandorganicmattercontentofthesoil,thegreatertheamountoflimestonerequiredtoraisethesoilpHtoadesiredlevel.

    Limestonerecommendationsarelocatedonthecomputerprintoutdirectlybelowthecroplisting.Unlessthelimestoneistobetilledin,applynomorethan50lbs/1000squarefeet(5lbs/100squarefeet)tothesoilsurfaceatonetime.Reapplyatonetosixmonthintervalsuntil

    thetotalrecommendedamountisadministered.ItwilltakeseveralmonthsforthepHtoincrease.

    Occasionally,itisnecessarytolowerthepHofasoil.SulfurisusedtolowerpHand,ifyoursoilneedssulfur,arecommendationwillbeincludedwithyourresults.

    EXTRACTABLENUTRIENTSPHOSPHOROUS,POTASSIUM,CALCIUMANDMAGNESIUMThenutrientions,phosphorus,potassium,calciumandmagnesiumareextractedfromthesoilusingamodifiedMorgansolution.Resultsprovideanestimationofthenutrientsavailabletoplantsduringthegrowingseasonandareexpressedaspoundsperacre.Valuesonthereportareclassifiedasverylowtoveryhighandreflectthelevelsfoundinyoursoil.Theobjectivewhendevelopingafertilityprogramistoachieveandmaintainlevelsinthemediumtomediumhighrange.PHOSPHORUSPhosphorus(P)isessentialforrootdevelopmentandtheproductionofflowersandfruit.NativeConnecticutsoilsaregenerallylowinphosphorusandmuchofwhatispresentisboundinbothorganicandinorganicformsnotreadilyavailabletoplants.PhosphorusismostavailableatapHofnear6.5andbymoist,warmconditions.Soiltestsprovideanestimateoftheamountofreadilyavailablephosphorusandrecommendationsaremadeaccordingly.POTASSIUM

    Plantsrequirelargeamountsofpotassium(K),whichissometimesreferredtoaspotash(K2O).Itiscriticalfornumerousplantfunctionsandespeciallyaidsinhardinessanddiseaseresistance.Potassiumisreleasedfromrocksandsoilmineralsastheyweather.

  • Soi l Nutr i en t Analys i s Laboratory ; 6 Sherman Place , Uni t 5102, Storr s , CT 06269-5102 Phone : 860-486-4274

    Fax: 860-486-4562 Locat ion : Union Cot tage , Depot Campus , Mans f i e ld Oftenthesupplyofpotassiumfromthesoilislimitedandfertilizationisrequired.CALCIUMAvitalcomponentofthecellmanufacturingprocess,calcium(Ca)alsoimprovestherootuptakeofothernutrients.Plantgrowingpointsareparticularlysensitivetoaninsufficientcalciumsupplyasevidencedbyblossomendrotthoseblacksunkenspotsoftendiscoveredonthebottomoftomatoesandsummersquash.Lackofmoisturealsocontributestothisdisorder.Soilsthatareproperlylimedgenerallycontainadequatecalciumbecausethisnutrientisamajorconstituentoflimestone.MAGNESIUMAkeyelementinthedevelopmentofchlorophyll,magnesium(Mg)alsoiscrucialtoseedformation.Likecalcium,magnesiumusuallyissuppliedbylimingmaterials.Dolomiticlimecontainingabout20%magnesium.Epsomsalts(magnesiumsulfate)mayberecommendedwherecalciumlevelsareadequatebutsoilmagnesiumislow.NITROGENPartofalllivingcells,nitrogen(N)promotesgreenleafygrowth.Lackofnitrogencommonlylimitsplantgrowth.Plantstakeupnitrogenintheformofnitrate(NO3)orammonium(NH4)withthenitrateformpreferredbymanygardenplants.Becausenitrogenlevelsfluctuatewidelydependingonenvironmentalconditionsandcanchangeeveninshipping,thiselementisnotroutinelymeasured.Nitrogenrecommendationsarebasedoncropneedsasdeterminedbyfieldstudiescombinedwiththepresumptionthatlittleavailablenitrogenremainsinthesoilattheendofthegrowingseason.Eveniflevelsofallothernutrientsaresufficient,youwillmostlikelyneedtoaddnitrogentoyourlawnorgardeneachyearandfertilizerrecommendationsaremadeaccordingly.VEGETABLEGARDENERSIfyourresultsstatethatboththephosphorusandpotassiumlevelsareaboveoptimumonlyanitrogenrecommendationwillbeprovided.Foreachpoundofnitrogenrecommendedyoumayuseyourchoiceof8.3lbsofbloodmeal(1200),17lbsofcottonseedmeal(62.51.7),3.25lbsofhighnitrogenlawnfertilizer(3235)or2.2lbsofurea(4600)per1000squarefeet.

    SOLUBLESALTS

    Solublesaltsaremeasuredbyspecialrequestforanadditionalfee.Saltlevelsmaybeelevatedinareasclosetoroadswheresaltcompoundsareusedfordeicingorwhereexcessivefertilizerhasbeenapplied.Highsolublesaltlevelscancauseseverewaterstressandnutrientimbalancesinplants.Asmeasuredbythislab,valuesformineralsoilslessthan0.4mmho/cmarelow,valuesbetween0.4and0.8areslightlysalineandmaycausesomeinjurytosaltsensitiveplants.Valuesbetween0.81and1.2aremoderatelysalineandwillrestrictthegrowthofmanyplants,whilethoseabove1.2areconsideredhighandlikelytocausedamage.Solublesaltlevelscanbereducedbyrepeated,thoroughirrigation.ORGANICMATTEROrganicmattervaluesareconsideredlowiflessthan4%,mediumfrom4%to8%,andhighifabove8%.Wevisuallyestimatetheorganicmatterofyoursoil.Mediumlevelsaredesirableforoptimalplantgrowth.Benefitsoforganicmatterinthesoilincludeimprovedwaterandnutrientholdingcapabilities;bettersoilstructurewhichenhancesrootgrowthandincreasesaeration;amorehospitableenvironmentforsoilorganisms;andareserveofplantnutrients.Soilshighinorganicmatterareeasiertodiganddonthavetobewateredorfertilizedasoften.Sourcesoforganicmatterincludepeatmoss,compost,leafmold,manure,mushroomsoilandmycelium.TEXTUREThetermtexturereferstotherelativeproportionsofthevariouslysizedmineralsoilparticlesnamelysand,siltandclay.Weestimatethetextureofyoursoilbyfeel.Whilecoarsetexturedsandysoilsmayhavegoodaerationanddrainage,theyhavelimitedabilitytoretainwaterandnutrients.Finetexturedsiltsandclaysarebestfromthestandpointofnutrientretentionbutmayholdtoomuchmoistureanddrainpoorly.Soilsdesignatedashighinorganicmattercontainsuchahighproportionoforganicmatterthatthesizeofthemineralsoilfractioncannotbedeterminedbyourmethodofhandtexturing.Loamswhichcontainfrom7%to27%clay,28%to50%siltandlessthan52%sandareusuallyconsideredidealgardensoils.Attemptingtoalterasoilstextureisdifficultandnotgenerallyrecommended.Thebestwaytoimprovesoilisthroughtheadditionoforganicmatter.

  • Soi l Nutr i en t Analys i s Laboratory ; 6 Sherman Place , Uni t 5102, Storr s , CT 06269-5102 Phone : 860-486-4274

    Fax: 860-486-4562 Locat ion : Union Cot tage , Depot Campus , Mans f i e ld

    Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Kirklyn M. Kerr, Director, Cooperative Extension System, University of Connecticut, Storrs. The Connecticut Cooperative Extension System is an equal opportunity employer and program provider. To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, Stop Code 9410, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (202) 720-5964

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