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.ry Grnulriu~
<br />' Capability grouping shoe's, in a~,eurl n;tc, the
<br />suitability of soils fur most kinds of Gelrl crop;. 'the
<br />groups are made according to the IimiLrtiuns of the
<br />soils n'hen used for field crops, the risk of d;unage
<br />when the)' are used, and the tt~a~~ the) respond to
<br />~reatment. The groupings do nut take int~+ :ucuunl
<br />tajor and generally expensive lanrlfnrming Uucl tcuuld
<br />change slope, depth, or other characlerrstics of the
<br />soils; do nut take into cnnsirleratiu^ possible, but un-
<br />likely, major reclamation projects: ;uul do nut apple
<br />to rice, cranberries, horticultural crops, nr alher crops
<br />requiring special management.
<br />Those familiar with the capability eLresi(icatiun c:ut
<br />infer from it much about the behatiur nl soils when
<br />used for other purposes, but this CInS5111Catrnrl rs not
<br />a substitute for iuterpretatimrs designed to shore suit-
<br />ability and limitations of groups of soils Ira r;m;,*e,
<br />moadland, or engineering.
<br />In the capability system, all kinds nl'sail arc ;[r,~ul,e,l
<br />at three lecelk, Che capability ch,ss. Lhe subcl;ss. and
<br />the unit. These levels are rlefinerl in the follott ing para-
<br />graphs.
<br />CA PAt;II,ITY CLAgSGS, tI1C bl'O;UICSI groups, :u'o ,1c.;ig-
<br />nated b}• Homan numerals I llrruugh l ill. 'I Ire nu-
<br />met.lls indicate Inognssively greater limilalinns and
<br />narrower choice; fur praclicul use, dcllned as lullutcs:
<br />Class I soils hace fete limitations Ut.ri rr~e(rirL
<br />their use. (None in I;in i; ranrlc County :\nsr.)
<br />Class ll soils have nunlcrnte limitations that rc-
<br />duce the choice of pl;wts nr tlrtt re,luirc aunt
<br />crate conservation practices. (None in I;iu
<br />Gr~uule County Area.)
<br />Class III snits L;ne severe limitations that reduce
<br />the choice of plants, require special cun;erc;ttiou
<br />practices, or both.
<br />Class IV suits hate verc severe lin,italiuns th:d
<br />reduce the choice of plants, rerluirc verc c:nefol
<br />nranngentent, ur l?uth.
<br />Class \' soils are nnL likely (u ernd,~ but Icne other
<br />limitations. imin:rctical In rcn,oyc. th:tl limit
<br />their use largclp br pasture, r;wge, tcondhuxl,
<br />nr wildlife.
<br />Class VI soils have scyere limitations hurt make
<br />them gener:rllc unsuited to cultitntinn and limit
<br />their use I;u~gely to pasture ur range, tcuudlaud,
<br />ur wildlife.
<br />Class \'ll soils hace eery ~eyere Iimit:tUons that
<br />make them unsuited In cultitalinn and that re-
<br />strict their use largely to pasture or range,
<br />tcourllanrl, or wiltllifc.
<br />CL•r.cs \'111 soils nnrl lanrlfnrms lone Innilatinns
<br />that preclwle their use I'ur cnnmurci;tl crop
<br />prrrrluction and restrict their use to recreation,
<br />wildlife, ur water supple, nr to esth„tic pur-
<br />poses.
<br />Cnrnrtl.l're Sunc'.t,nsses ;ue u?il ;,+ruups within one
<br />class. '~he> are designated by arldiug a small letter, r,
<br />n', c, or r•, to the class numeral, fur ex:unple, ll le. The
<br />letter r- shows that the main linrltntiun is risk ui' erosion :
<br />that water in nr un Lhe soil interferes tviUr plant
<br />groteth or cultivatiuu (in some soils the wetness can
<br />be partly cnrrecterl by artificial drainage); s shutrs
<br />that the soil is limited main)}• because it is shallow.
<br />bought}', or stmty; :utsl r., used in only some parts of
<br />he United SL•ttes, shows th:+t the chief limibrtiun is
<br />climate that is too cold m ton dr;y.
<br />In class 1 there are nn subclasses. 1?ecause the soils
<br />of this class hace few limitations. Class \' can contain,
<br />xt the most, Duly the subclasses indicated b}~ ,r, s, «nr1 r.
<br />because the soils in class C :ue sul?ject to little ur nu
<br />erosion, although the> have other limiUrtious that re-
<br />strict their use largely to pasture, range, woudlanrl,
<br />I;APAI:I I,ITY UN~:ue Coil groups u-ithiu the sul,-
<br />classes. 'fhc soils in one rapabilil\ unit :n'e enn~.tgh
<br />;dike to he suited to the same crops and pasture Plants,
<br />to require similar management, and l~+ hace Similar
<br />prurluctit~it~~ and other response. to ur;ura~!ement. 1'luts,
<br />the r;IpaIllllt\' ^mt is a cnnccnienl growling for nmk-
<br />ing m;mV- slntentents nbunt nuucr~~,cmen( of soils. Cnl,a-
<br />Lilit> twits arc generally desip,ualcd be adding an
<br />Arabic numeral to Lhe subclass s}ndn,l, for exantl+le.
<br />llle ° nr I\~e-I. Thus, in rruc ~cminil, the P.unuut nu-
<br />meral rlesignatcs the cnp:rl,ilit~ class. or decree of
<br />limit.•ttion; the small letter iurlicatr- rice ~uhclas=. or
<br />kind of limit;ctirrn, ns dclincd iu the Inreguin~ laru-
<br />graph: and the Arabic autocrat specillcall~' idattilles
<br />(he c;rpnbilit~' unit within each snltrla=~.
<br />I1ruu~Crnu•nl In~ rvrprrbi]ilt~ unil..~
<br />The capability units in the trio e.;rsndc C'nuut} :1rca
<br />;ue described nn the p.+gc~ that 1u11ott, ;uul use and
<br />nuwagemeut is suggested for the sails in e,rch unit.
<br />Alnmsl all the irrigated snip in the =i, rt r} :u e:t :ue
<br />in capability class Ill or I\ . (Ini,pcr lu:uny sand, hnc:-
<br />erer, is in class VI. Because the i~,ld climate and start
<br />grmriug sr;tsun are severe limitati„us l„ use of the
<br />soils fur crop,, no soils iu ihr :\rc:, :u~r, in ,~i;tss I or Il.
<br />In grouping the sr,ils into irrtgatc,l rnl:rhlllly unit.. it
<br />is asauncd that cultic real tratcr is at~nll:rLlo lur irri-
<br />gatinu and that, the suite aro irrig;dal. Vnnirrl;~nf~•d
<br />soils arc in cLcss \' Utrnttgh \~I II. 'I'het~ :rrc nnl suilal4r
<br />for culLicated crops because of the ,b~y clinr,rte nr utlwr
<br />soil conditions.
<br />'fo liud the nanu:~ ~+l' all Llre soil. in ain ;;icon rrln
<br />hjlity unit, refer to the "l~uid,• to \I Aping Uniis° al
<br />the bacl: of this carver.
<br />crr,oui.rn use .n.._,
<br />'1'Itis unit cnusists of deep. nvxlcral,•It 1,crnrcahlr.
<br />tyell draiuerl „r mwleratclc tt ell ,Irnir,c,1 ,,; arcs. Sl of v:.
<br />are 1 to ; I,ercenL.'I'he atnilal,lc ttalrr , al,ncilt i.. hi~,h.
<br />'Pllese Bulls ore irrigated. 'I'hc 1'ru~l-Ircr ,,arson is'.tn
<br />t0 llo fl:r1's.
<br />'These soils are suited t„ irrigated rn,ls anal to unra
<br />crops grutcn in Ute Area. 'I'hec ai~~ ak„ ~uibal t.. I,•s::
<br />intensive uses, such as irrigated I+a>tu rr. ;imuolh
<br />brnmq nrchardgrass, intermediate tch,~ntgras=, ltu~-
<br />sian wilrh~ce, stveetclncer, and ^Ifal1'a Ilig 1°_1 arc
<br />some of the roust cununonlc grutcn I,lanl. fur irri~alyd
<br />pasture.
<br />'the slope and the control of irrl~,:,lien tcater are
<br />Lhe aorta concerns of m:nn,gement. Irrit~^tinn hate,.
<br />mauagamenL. fertility mainten;uice. I;unl lcceling.:unl
<br />crop rul;tliun protect the s„il mainst detect„ration :aid
<br />help to maintain production. Furrows, , ~~ntour furru~.c.,
<br />rnnluuc ditches.:utr1 sprinklers err snltal,le lnr irri;;a-
<br />Liau. 'the Icuglh of runs shnul,l be churl to control
<br />ermine. Alauaging the irrigallnn tt:rlcr is easier in
<br />areas lbat eau he leveled. A crnppin;; syar.m that i~-
<br />cludes. clrse-growing crops :uul Ic~wm•> :uul nnlr r
<br />limited number of row crops brigs t~~ nuriulain filth
<br />and fertility.
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