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TECHNICAL BULLETIN No. 609 June 1938
CHEMICAL AND PHYSICAL PROPERTIES OF CERTAIN SOILS DEVELOPED FROM GRANITIC MATERIALS IN NEW ENGLAND AND THE PIEDMONT, AND OF THEIR COLLOIDS
By IRVIN C. BROWN Associate CIWl1list nnd HORACE G. BYERS Principal Chemist Soil C/zc'lI;stry a"tl P/ly.des Rc.f'!Orcll Di.,;s;on Durellu oj C1H!tnistrY arId Sails
UNITED STATES DEPARTMENT OF AGRICULTURE, \VASHlNGTON, D. C.
For Bale by the Superintenuent of Document', Wnahington, D. C. ------• - - - - - • Price 10 cents Technical Bulletin No. 609 June 1938
UNITED STATES DEPARTNlliNT OF AGRICULTURE WASHINGTON, D. C.
CHEMICAL AND PHYSICAL PROPERTIES OF CER TAIN SOILS DEVELOPED FROM GRANITIC 11ATERIALS 1 IN NEW ENGLAND AND THE PIEDMONT, AND OF THEIR COLLOIDS 1
By IRVlN O. Bll.OWN, as.~ociatc cit(;{nist, und HOltACE G. BYERS,principal chemist, Soil Chemistry and Physics Uesearch Division, B!treau oj Chemistry and Soils
CONTENTS Pnge l'll~o I Introduction._•..•. I Aualytical results-Continued. Descrlptiouofthosoii'<...... a UIDuco,tcr sandy hmlll ___ .. Brossu:L ::o:rie:;. ~ ~_ :)1 (·I.W~lUrlonUl~ __ ~._ -~ llermun sorh\~ . .j I Milnor loam...... G ~OUl'cster scrie:-,_ fi I ('(wi! sandy clay loum_ .. Chesler sorie' t1 ' AfJpli[)~ suudy l .... "ltJl. l\Inuor sori('s~ ~ .. __ I TIygroscopi(' rolnt':f111~L_ 4_".~ •• f'ecilsoric8.•.. ___ ..... H (·lIrhon·uilro~'··. ratios __ ..... Appling scrimL . _ _ U Oc.merni disc dssioll_ .. l\[ethlld~ or exuminllLioIl. HI SUlllmury___ ._ ~ ____ .~_.~ __ *'~ __ .Analytlcal rC~llll~ .. ~. __ ~~ ___ ~_~~_._ ~~_ .. __ ~.~_ II Litcruturo c ted__ •______.. _ ___ . __ ..._____ . IIrussun sundy loam..___ _ II Uormon sllUdy loam ..______. I';
INTRODUCTION
The Illt~ C. F. I\Iarbut has present~d the broad scheme of soil classificl1tion fOt' the United States in part 3 of the Atlas of American Agriculture (25).2 Although it is 1!1rgely based on the extensive field studies of tbe Suil SutTey Diyision, other SOUTees of information have not been neglected. In tracillg the genesis of soils he aneL many others (32) have emphasized the pnrt played by pnrentmateria.ls,climate(tem pemture and raillfall), and vegetation, as well as the whole biota, in the evolution of soil chu,mcteristics. A tremcndous volume of ana lytifcal data is in harmony with his conclusions. In 1905 Cushmun (15) and ill HlO7 Cushman aud Hubbard (16) demonstrated the efJ'ectivcness of "\H1tl'l' in decomposing finely ground rock powders. This was recognized by RarntLnn (34) in 1911 as the principal reaction in soil lonnn,tiOll. Within the last 15 yen,rs it has become incrensillgly ltppl1rell t to pedologists th:tt the hycll'olysis of minemls is the dominant cher,lien,l process in the production of soil colloids. However, the filial cltamcler, ns noted by Freise (18), is influenced by various cilemicn.J, IJilysicn.l, and biological processes whose importance is lllensureJ lIy their reln.tive intensic) in specific soils. Iteeently AlexlLlldcl' u.wl Byers (2) lULYe produced mn.terial very
I Hcceived ror pulllicntiou Septemiler 2, 1!137. 2 Italic numhers in pnrenthcsl!s l'df(!1" to Llturnturo (~ited, p. tH. 33453°-38--1 2 TECHNICAL BULLE~IN 609, U. S. DEPT. OF AGRICULTURE closely resembling colloidal clay by alternately grinding and electro dialY2.ing anorthite; considerable time was reqllired and hydrolysis was not quite complete. In 1924 Robinson and Holmes (39) published a paper dealing with the chemical composition of soil colloids. The data contained therein show in a striking manner the close correlation between climate and the composition of the soil colloids. In 1928 Holmes (21) presented data showing the similarity of colloids ingiven horizons of the Leonard town silt loam. In 1930 Holmes and Edgington (22) presented data derived from the colloids of the :MiiLilli, Chester, nnd Cccil soil series, which belong to the Gray-Brown Podzolic and lateritic groups. 'rhese results indicate thn.t the colloids not only nre similar within n given soil series but tlmt thpy fire essentin.lly ditl'erent in different soil scries. In 1932 Byers n,nd Anderson (14) extended the study to certn,in of the other major' soil groups recognized by the Soil SUI'\'ey Diyision {wet defined by :Marbut (2:)). In 1933 Byers (12) digCllSSed the constitu tion of the hypot1tetien.l soil acids whieh may be present in the soil colloids nnd therefore l't'sponsible for tho chttmetol'istics of the great soil groups. In 19;);) Bl'Owll, Riel.', iLlld Byers (10) noted that ClaYPl111 soils bdonging to the Pmirie nnd ChenlOzem groups yielded colloids of remarkable uniformity both within the series nnd in closely related series. An annllttlminftLll l't1.llgiug from 13 to 32 inehps npl)en.red to pltty no dODliruwt role in the composition of these coUoids. TIl('rcfore in ] 935 Brown ltlld Byers (11) extended the study to certnin soils of the westem p!1rt of tbe Great PitLins in an efrort to dl'tcrll1iIle the efl'ect of n, eOllsidemble y!tria.tion in tpmpemture. Quite surprisingly, no cOllsisten t l'chttion bl'tweell colloid com position n.nd temperature appears to exist. Instl'nd, it appears eertniu tlmt the low moisture content of these Roils minimizes the c(reds of tL'lllpemture, so pro nounced in tile 11 umid al'PUS, and allows the parent llultprial to domi nate tho clmmd('l' of the mill('ml colloids. Indeed, it had hecllnotcd previously by HobiLson, Edgington, aIld Byers (38) that the parent rod;: of certain soils of the humid al'e!ts has a profound influence on tile composition of tbe soil and colloid. In 1\)36 Bnldwin (7), H,llSscl (40), and Robinson (37) prpsented various ebemicn.L iLnd ll1inemlogicn.l -,. ltIHtlyses of ·willll-tmnspol'tl'cl dusts which jnelicn.te tlmt the surfnce soils and eolloids mn.y be modified by n.C'cuDlulatiolls of considerable quantities of clwit hom other [treas. It is n.ppm'l'Ilt., howpvpl', m; l11l'ntionpd by :Mnl'hut (2;;, p. 16) and others, titn,t the soils me to it greut extent the pl'oduet of' those factors whiC'h illfiue!.1<'e nud in a measure coutrol the developnwllt of livillg m!ttter. In otliPl' words 1ill0Y are iI1liuenC(~d more hy the pbY1'ical environment as a whole than hy the eilametel' of their parent rock. The direct ,p!l'ef'.ts of elima.te in humid aTeas m'e marked. I t seemed. Llil1J'P[01'e, yery ·worth while to mnke a S},StC'llULtie study of soils develOped in a humid area in which the soil faetol's r.l'e reaSOIl ably eonstnut in nlll'espnets other than tempemtm'e. Sueil nu area exists aloug tho oastern slopes of the APPfLln,chiiUlS in New Engln,nd and the Piedmont. 111 this area a wide l'n.nge of soil serif'S is developed from grn.nitic mn.tel'ial ill which the ('hief illOl'grmie (,olloid-fol'ming • material i1.ppel1rs to be di- l1nd tri-siliel1Le Jeldspu.rs. The mean annual rainfall does llot hltve all exeessin\ly wide range, and it is highest where evapornLion is greatest. 'rhe vegetation !Llso, while somewhat ~ variable, is of the sILme geneml charaeter. The mean tLllllU!U tompem PROPERTms OF NEW ENGLAND AND PIEDl\IONT SOILS 3
ture has a wide ru.nge, and its efl'ects m'e aceentuated by great seasonal difl.'erences, With these conditions in milld the Soil SUl'vey Division was requested to cooperate in the collection of reprcsenttttive profiles of typical soil series best adapted to the requil'ements of tile proposed study. Special care was taken to include certain profiles of soils llot previously studied in this laboratory but similar in general chttnwter to profiles of the same great, groups on which detailed studies have been made, This permits the advantageous use of a considerable body of data previously published and enlarges the scope of the investigation, Conscquently, libel'lL1 use lin,s bN'1l made or illforma tion and data from SOlU'ces cited, The du,f;a submiUed comprise the results obtained, DESCRIPTION OF THE SOILS The soils selected for this study tlJ'e from the l'odzol, Gmy-Brown Podzolic, Red, u.nd Yellow (essentially laLeritiic) groat groll ps of soils as defu1ed by :Nhl'but (25), They rcprOSCll t ccrtttin impol'tnnt soil series which are agl'icmltunilly important in New Engb,nd and the Piedmont region. They range from New Hampshire in lIorthern New England to GeOl'gin, in the southem part of the Piedmont. The mCllll annual t'i'mperatm'e ranges from 430 to 62.20 }i'.; the mean annualrninfall is from 39.16 to 50.18 inches. The llative vcgetl1tion does not differ markedlv. For the purpose of sliowing the relation between the soil series and a particular profile, a gCllcml description of each soil series, JUJ'nishecl. by the Soil Survey Division, is Jollowed b~r a, detailed description of the representative soil profile. Various In,yers of each soil arc sufli ciently defined to permit the charn.cteristic horizoll designations suggested by Kellogg (23) to be used. with security. HowcyOl', all the horizons nre llut always prescLlt; 1101' is it to be Q),'-pected, although every soil has some of them. BecttUse of this condition the layers of the soil series Ilfl.ve becn 11 umbered. TIlCY l'epresellt tJlO dmmcteristic layers most often present in a, t)Tpieal prof-ile of the s0ries. The agreement hetween tlle soil and the scries is not al WHyS npparcnt, ~~ therefore, unless the possibility of missing members in cither is taken into account. llRASSlJA SERIES
The Brassllu SCTIC"', found on g01ltlc sloprs of high pln.teaus and mountains of nortlLCrn New Englund, indudes strollg]:v acid Podzols developed from granitic find gneissic glucial tilb. Tbt')T me similar to the soils of the Hennon sories hu t i'urtiwr developc'd. The B horizon is t1 httrdpan 01" ortstein, which varies somcwhut in thickness nnd degrce of cementation. The clruinngc is llu'gC'iy internal and good. The llnturnl vegetation consists of .lwllllock, sprUCE', white pillc, yellow birch, and popliu'. The stony nnd suudy types aroused ulmm;t {'uti.rcly for forestry, while the loam produces good yields of mowiJJg auli pasture grasses. Characteristics of members of the series arc as follows: 1. Leaf litter lind raw hll111I1S llltLt. Up to 10 inclws tllicl" 2. Gray or whitish-gmy sUJIll'wimj, plnty Of" phy.llirof"m stOIlY sandy loam which easily breaks down into !L single-gmin ::;trnctllre. AIJOllb 4 or 5 inches thick. 3. Very dark brown friable Iliony loam coutaillillg lllllch orgtwic lllatter and some small fragments of yellowish-brown iucillmted matcrittl. From 1 to 3 inches thick. 4 TECHNICAL BULLET.1N 609, U. S. DEPT. OF AGlUCULTURE
4. Yellowish-brown indurated stony loam or clay loam material. From 6 to 8 inches thick. 5. Brownish-yellow material similar to 4 bll~ liglltE'l" ill color and texture and less indurated. Up to 10 inches thicl,;:. 6. Brownish-yellow sandy till, about 8 or 10 inches thick, grading into yellowish gray, stony gritty till composed largely of granite and !,'1leiss.
BHASSUA SAN1JY I,OAlIl In Grafton County, N. H., tlle Roils of the BmsRun, series are con fined to a few aTeas. They htwe a good stand of coniferous and hard wood trees. 'rhese soils are mapped as Hermoll soils becn,use they cover areas too small to be recorded. In fact, the Brassua was mapped as Hermon before the profile distinction of the new series was recognized. Climate: Mean lUlIlual rainfall, 30.Hi inehel'; mean anllll!l.l iempemtllre, 43.0° F. Location: 1 mile east of North Groton, K. n., on northwest slope. Vegetation: Heavy stand of spruce with scattered yellow birch and maple trees. Undergrowth of moss and blueberries. Collectors: W..J. Latimer and r. C. Brown. AD, 5 to 0 inches. Black forest mold. Crumb structure. Combined with AI' AI> 0 inches. A gray discontinuous layer. WelLldy developed. Not sufficient to be sampled. A., 0 to 3 inches. White sandy layer (bleicherde). Amorpholls, sugary structure. BI> 3 to 4 inches. Rusty-brown slightly ccmellted sand. Thig is a ZULle of organic matter accumulation. B" 4 to 9 inches. Yellowish-brown :-;trollgly cemeuled Illtllcly layeI'. R3, 9 to 19 inches. Light yellowish brown ·Lo gmy slightly cemented ~lLucly layer. C, 19+ inches. Pment material uf gray glaeiai till.
HERMON SEltIES The Hermon series wus esLn,blished ill ] ll2:J t.o ineiu HEHlIION SANlJY LOAM , The Hermon soils 111'0 wides[>l'Cltd in New ITnmpHhire, llslln.1Jy oceur ring at moderate elevntions. TJJcy n l'e spn.rillgly forested 0[' occupied by undergrowth, and covered with grasses if UI.eln,nd hits been cut over, PROPERTIES OF NEW ENGLAND AND PIEDlVIONT SOILS 5 The profile is somewhat diffuse, anel the horizons merge into each other by imperceptible grada.tions. Climate: Mean anmml rainfall, 38.64 inches; mean annual temperature, 43.4° F. Location: 4 miles north of Canaan Center, Grafton County, N. B. Vegetation: Moderate growth of maple, white birch, and white pine. Collectors: W. J. Latimer and 1. C. Brown. AI> 0 to 1 inch. Fairly well digested organic matter alld Roil. A2 , 1 to 5 inches. Gray or light-gmy sand containing a few hrown slr'eaks at the top of the layer. The structure is amorphous. BI> 5 to ]5 inches. Dark-brown sandy loam becolllillg induraterl in spots on exposlll'{,. Single-gmin structure. B2, 15 to 2.1 incheB. Yellowish-brown sandy loam. Single-gmill structure. Ba, 24 to 32 inches. Pale yellowish-brown nmi;eria,l fading into yellow to gray gritty till. C, 32--\- illcllPs. (1 my, gritt.I' glaC'ial till c1el'iI'C'c1 from granite. GLOllCl~H'I'EIt Hlmms The Gloucester sprim; was established in 1904 to cover most of the upland well-tl:rninocl soils in JUlOdo Island. As a soil serics it has been mapped in many parts of New Engbnd, New ,Jpl'sey, and New York and other Litke States, usually covering soils developed from glaeinl till overlying ancient schists, gDPiss('s, and granites with little or no fmther clifferentintion. In the Slll'vey of Worcester Connty, Mass., in 1922, its chal'lI.eteristies were 1110re funy described and its range was restricted. The1'('lief is rolling and drainage good. 'rhe native vegetation consists of oak, maple, birch, and white pine. The characteristics of members of the Gloucester series, as now defined, me as follows: ]. Loosc forest litter ami raw humus mat ranging up 1,0 about 2 inches. 2. Brown to strong' darJdsh-brown material. LiJw _itl> associatcd Hoils, the Charlton and Broekfield, it coutains , l1 ueh brown to clm'kish-brown organic matter. 'rho Jayer ranges up to a thickness of ahou!; 4 inehes. M!tterial is friable but structureless. 3. YeI1owish-hrown friahle siructurclells material ranging up to about 7 inches in thicloWHs in the lig-htpr textured mombers of 1he seril's. 4. y ollowish-hro\\"11 to yellow, ranging' to T,ale-yellow or grayish-yellow material. Friable, stl'l1c1:\Il'pless but ypry slightly heavier than the material ill 3. Thickness of the lay<'1' rang('s up to aliout a foot. ii. Grayish, llI()(lerni.ely to \'(,I"Y sanely gl'l1)' glariu.l till made U]) mainly of JIlaterial from gmniieR or gmnitic p;neiss. 'The Gloucester silt lOlllll in the yicinity \\'11('1'0 the sample was collN,ted is weJl-dmilwd, nnd soiI-fol'ming pl'oe('i:1ses ('xtclld to a depth of 30 inelH's. The topogr::.ph.v is lllHlulating to rolling. The parent material is slightly uJt.ered glaein.l tillidt by the last ice sheet. Clill1a{w Mean anl1ual rninfll.ll, 3!l.1i7 in{'hcs; moan annual iC'lllpemtuJ'e, 48.3° F. Lo('ation: One-hulf Illile south of Medll'u)', Norfolk County, Mass., 100 feet east of a T road on south side of roacl. Vegetatioll: 80ft JuaplC', s(,l'uh oak, al1d ll. fcow scattered pille trees; cut-over land. Collectors: IN . .T. Latimer ancl 1. C. Brown. A" 0 to 2 inches. 8nrfnco 1:1.1'('1' of lell.\·cs alld partly decayed organic matter and, roots. Can be pullcod lip like n. mat. It includes one-fourth inch of a thin incipient, {rI'l1Y dis('ontiul1ous A2 lttyt'l' which is a part of the AI' These could not be sepll.mtely SfLll1plt'Cl. BlJ 2 to 3 illchc~. Coffee-hrowil layer of sandy loam that grades into the layer beloll'. B2, 3 to 15 illches. Finn, yelJowiHh-lH'own friable sand,\' loam tlw.t fades gradually to a pale yellowish browll. 6 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE Ba, 15 to 30 inches. Pale yellowish-brown light sandy loam. Differs very little from the layer above. Very little structure observed. Grades gradually into grayish yellow. C, 30 to 40 inches. Gray, gritty, unaltered till which is derived mainly from granitic material. Probably eA-tends to a depth of 20 feet. Fairly firm. Breaks easily. GLOUCESTER SANDY LOAlI[ (NEW JERSEY) The profile is IOC'fltpd on the termillnl moraine of the .Terseyan gla cier, the remaim; of the oldest C'ontinentnl g1nciatioll in Norilt America. The parent mat.crial of the soil hns bE'pn nltE'red to a nn.:.c1 grentcl' depth than that of the Glouccster soil in 11nssnc\msctts, [Iud th(' horizons nre not so sha.rply defined. TJlls is clUE', no doubt, to the differences in the age nnd. character of the two drifts I1S 'well as to clitferences in dimut.e. B('canse of th('se CHESTElt SERIES The Chestc·r series was C'stn,blished in 1905 to indude soils deyeloped from ]'csi 5. Brownish-yellow to reddish-yellow soft, friable, micaceous clay loam. Much looser than the material in 4. Downward this changes into loose disinte grated gneiss which varies widely in color. CHESTEH LOAM The predominating soil type of the Chester series is a loom which is no doubt inherited from granitic parent material. It is one of the most important and fertile soils of the Piedmont, and is found as far north as Pennsylvania and as far south as North Carolina. Climate and other influences, however, are purticularly favomhle for the best development of the Chester loam in the :Maryland and Virginia soils. Climate: Mean annual rainfall, 40.16 inches; mean ann11al temperature, 54.3° F. Location: Near the road 3% miles north of Rockville, Montgomery County, Md. Vegetation: Mixed hardwood and pine. Co]]ectors: W. E. Hearn, L. B. Olmstead. and W. (.'. Smith. Ah 0 to 2 inches. Dark-gray to dark-brown loam containing considerable organic matter. There is a very shallow cO\'cring of leafmold on the surface. A2, 2 to 10 inches. Light-brown to brownish-yellow loam carrying a high per centage of silt. It is mellow and friable. The AI and A2 layers constitute the eluviated horizon of the profile. B1, 10 to 32 inches. Brownish-yellow to yellowish-brown, heavy clay loam or lighii clay, containing some small sculrs of mica. This layer is uniform in color. It is friahle and crumbly, and breaks into irregular-slw.ped lumps easily crushed hetween the fingers into a fine granular mass. The color is uniform throughout these lumps of soil except in a few places where there is a light-gray coating of colloidal material. Cit 32 1\0 64 inches. Brownish-yellow to reddish-yellow soft, friable clay loam containing a sufficient amount of finely cliyiried miea seales 1,0 gh'e it a greasy feel when rubbed between the finp;ers. The material in this layer is more friahle than that in the HI' Around 48 to 50 inl'hrs it grades into soft dis integm,ted gneiss or granite, which is friable ami crumbly. The color is yariable but dominantly lighter than that of the BI horizon. MANOR SERIES The 1fanol' series was established in 1900 to include soils in eastern Penns~ylvania derived from highly micl1ceolls schists and hn,ving a normal butimperfeetly developed poclzolic profile. As compnred with that of the associated Chester soils, the profile is but slightly developed, which is due in pnrt to the slow decomposition of the micaceous rocks and in pnrt to the strong dissection of the region anel the occur rence of the soils on slopes. In the locn,lity where the soil was origi nn.lly defined, these soils are in about the same stage of development as the I~ouisa soils of the southern Piedmont. Thev are less well developed than the Maclison soils. . By the time 1iontgomery County, lvld., was surveyed in 1914, the significance of the stage of soil development wns more clearly recog nized thnn in ] 000, so that the MallOI' soils in thnt county are defined as undeveloped soils eonsisting of deeompositioll products of crystulline rocks. These also constitute the parent lllnterials of the Chester soils. Profile development is veryslight and cOIlsiderl1,blyless thanin the origi. Ilul :Mauor soils, in the definition of which the geology of the pnrent material was a more important factor than stage of dfwelopl1wnt. As 110W defined, therefore, the J\fn,nor soils do not include much of the soil identified as J\1n.nor in the original area. A now series to include partly developed soils from highly lnicftceotls material in the northern Pieclrllont should be established. Tho relief is rolling, these soils oceulTing mainly on relatively steep slopes. Draina.ge is good. Heaction is lLcid. 'J'be native vegetation 8 TECHNICAL BULLETIN 609, U. S. nBPT. OF ACRTCULTlTRFJ consists of a vigorous growth of ou.k, yellow poplu.r, linden, and locust. The characteristics of the members of the 11anor soils are as follows: 1. Forest litter and lel1fmold about an incll thick. 2. Dark-colored material, usually daTk hrown. Thc material is usually aggregated into angular paTticles and impcrfcci.ly shl1ped granules. The thickness ranges up to about 3 inches. 3. Brownish to light-brown ma,tcrial about 8 inches thick. 4. Brown material. Itis slightly dc£'p£'r in color than 3 and but slightly heavier. The material consists essentiaJ1y of rli~intcgration products of gneisses and schists. It grades down into the uncilangl'd rock. MANOR LOAM Surfa,ce drainage of the l\'fanor soils has caused most or u.ll of the surfu.ce byers to be removed by erosion. "\Yith this exception they are essentially lilm the Chester soils in Mu.ryland and Virginia. Climate: Mean annual rainfl11J, 38.19 ill('he8; IY1Can annua.l tempemture, 54.10 F. Location: One-third mile soui.hwest of a large white churrh on the west side of Highway No.7; 2.8 mil",> north of Tysons Cross Roads, Fairfax COllnty, Va. Vegetation: Wooded area forested with white, red, black, and post oaks, and a few popbr, maple, and loc1lst trees. Origiually there were many chestnut trees. Collectors: W. E. Hearn and L. T. Alexander. A" 0 to 1 inch. Leafmold wiih a small amount of mineral matter. ..12 , 1 to 8 inches. Yellowish-brown (under moist conditiom;) 10aJU to silty loam. Mellow and friable and has a slightly greasy, slick feel when rubbed between the fingers. BII 8 to ] 7 inches. Slightly durkl'r colored than the layer above. Heavy silt loam containing a few small schist particles. It is mellow, friable, slick, and greasy. This layer shows slight illuviation and is the heaviest layer in the profile. B2, 17 to 40 inches. Light-red, purplish, anel yellow, soft micaceous material with SOllle black streaks. Incorporated in it arc some light to dark or silver colored schist fragments. The suil is \'ery soft, friable, and micaceous, and has an extremely greasy feel. C, 40 to 50+ inches. Mingled yello\\' to grayish-yellow ocherous and somewhat black streaked, soft, disintegrated, and jlartly de('olllposed light-colored schist. Very friable and micaceous. CEcrr. I'lEIU ES The Cecil series wn.s 0stn.blishcd in 1900 to include soils with yellowish A horizons and B horizons "vith some ],0d, usually strongly yellowish red. TexturC's nre hcavy. Thuy fj,re dcvdopcd hom materiaJ resulting from the d0C'f\,Y of the gnC'isses and in pfI,rt the schists of the Piedmont region. The soil W:I,f; fir"t ddined in Cecil County, Md., and for several yea!'s after the estl1blisbmcnt of the series, soils were identi fied as membel's of it throughout the Piedmont rcgion. The mor phology and color of the profile were the only bases for idcntifying its members. In time, certain soils were split off as independent series, but the most fundamental chn,nge in the criteria for identifying its members was introduced as a result of the study of tIle colloids o(the soils along the Piedmont. These studies luwe shown tllfLt in Georgia and Ala bama the decomposition of the rocks 1ms gone further than in the • northern Piedmont, the thoroughly decomposed parent material in , the former region having lost so large a proportion of the silicate silica ori~inally presen t ill the rocks as to red uce the silica-alumina molecular ratIO to less thlLn 2. In the northern Piedmont that stage has not. been reached. At present, the northern boundary of the Cecil soils PROPERTIES OJ!' xmv ENGLAXD A:ND PIEDlVIONT SOILS 9 is in northern North Carolina. That limit has been based on a rich accumulation of colloidal data. It may be shifted somewhat in the future. The characteristics of the members of the Cecil series, as now defined, are as follows: 1. Forest litter and leafmold about an inch thick. 2. Dark-colored, structureless mineral soil. In the normally developed profile it is usually sandy. The thickness may range up to about 2 inches. 3. Yello,,;sh, sometimes with faint reddish shade; usually sandy in the normal profile. In large areas of the southern Piedmont this horizon has been partly to wholly removed by erosion. The farmer now plows the red clay or sandy clay of the former B horizon. The thickness lllay range up to about a foot, depending on the percentage of quartz in the underlying rock and the aUlount of erosion. 4. The B horizon consists of red to yellowish-red clay or sandy clay, which may break into angular but very soft, easily crusbed particles, from half an inch in diameter down. The color of the upper part is deeper, and this part is usually heavier also. The Jower part is slightly more yellowish and lighter in texture. The reddish eolor is usually dceper on the outside than onthe inside of the particles, but those in the upper part of the horizon may be coaf.ed with a thin layer of the yellowish material from ahove. The thickness may range up to 3 to 5 or 6 feet. 5. Loose material which may consist of a considerable proportion of reddish clay matrix in a mass of disintegrated but illcompletely decomposed minerals, mainly feldspar, quartz, and mica. This material, which varies in character, may extend downward muny feet, becoming grudually more and more like the undeeomlJosed rock. CECIL SANDY ('LAY LOAlII The ('ecil soil~ are. wideflpreud. Tl1ry arc important soils in the southern Piedmont in spi(,e of tlHl ranlgcs of rrosion. In mnny nreas the light-yellow surIarc soil i~ J"rmond, lrHying the compart heavy clay of the lower lUYl'rs exposrcl. The profile brJow is essentially complete, although the A lnyrr is ])0('. flO d('rp ns might be expected of a profile undisturbed by ('rosion. The 0 Jny('r is t1 transition layer but more like the C thnn the B. Undrrdmillng(' is Jair. Climate: Meul1 allllllttl rainfall, 49.97 in('hC'l'; mcall anllual telllpenttufl', 58.8° F. Location: Erosion C'xperillH'lIt Rtatioll lo('atc(l ] 0 miles w('~t of Statesville, N. C. Vc/!;ctation: The trC'es ill this yieinity arc lllOI't1y ]w,!'!lwoodfl. There are some pine. Where the RtI,JJlple was takC'll, ihe soil hail b(,C'n far-wed for some time. Collector: J. 'V. SlIrdC'r eullederl the first three laYers ill 1930. He collected the lowest lay.cr at tlic ;-;::Ulle locution a~ [L bier elate: A, 0 to 6 illches. J,ight-i>rowll I'fI,[J(ly loam containing yery little organic matter but marc than either horizollll HJ or B~. BJ, 6 to 32 inches. Reel ("lay loalJl. Vcry uniform and compact. B 2, 32 to 60 inches. Red clay loalll with brown lllottlin/!;. Very compact when exposed and has a 1.elldeIH·.\· to (Tuck. C, 60 to S4 inches. COlllpll't!"ly di> The characteristics of members of the series are as follows: 1. Forest litter ll,nd leafmold about an inch thick 2. Dark-colored mineral soH which may be imperfectly granular. The thickness ranges up to about 2 inches. 3. Gray to yery pale yellow, structureless material ranging up to nearly a foot in thickness. 4. Yellowish to pale-reddish material, which is usually heavier than that ill 3. In exceptional cases the color may be red, but the dominant color is pinkish or pale red. The upper part of this layer is usually paler than the lower part. It usually breaks into a mass of small particles on drying. The thickness may range up to about 2 feet. 5. Mottled light-red and yellow, hard but brittle clay about a foot thick. It is friable and mellow. 6. Disintegrated gneiss and schist rocks, mottled "ith white, gray, red, &ild yellow. Th"! relief is smooth to depressed, drainage is imperfect, and reaction acid. APPLING BANDY LOA..>J: In spite of g-oocl surface drainage the undel'dl'ainag-e of the Appling soil is not we'll established. The eluviated horizons are thoroughly leached. The light-yellow color of the UpP('1' horizolls testifies to the intcnsity of both leaching- and c]uviation of those layers. Mottling of the subsoil is unessential characteristic of an Appling profile. Climate: 1\1ean annual rainfall, 50.18 inches; lUcan annual temperature, 62.2° F· l .. ocation: 3% miles northwest of the courthouse of Elberton, Elbert County, Ga,.; one-eighth Jl1ile south of Goss, Ga.; 150 yards west of the highway in a groye of pines an([ 011].;:8. Vegetl1tion: Blackjack onk, red oak, scattering of old-field pines or second growth; hickory, wild. cherry, and hlack gum; SOlUe broolllseclge ill the open spaces. Collectors: S. O. Perkins nnd 1. C. Brown. Ab 0 to 1 inch. Leafmold consi!-;ting of partially decomposed leaves, twigs, and roots mixed "ith a small percentage of light-gray sand. A 2, 1 to 9 inehes. Yellowish-gray light sandy loam. A3, 9 to 14 inches. Faint reddish-yellow sandy loam. Hb 14 to 28 inches. Yellowish-red ]1l'lWY crumbly hrit.tln clay which hreaks u]1 inio granular fra,gmellh;. It is ea~ily crushed betwcen ihe finl!;t'rs. The lower pLlrt of this hOl'izoll is st reakec\ with yel10w alld ishea\'i('l' t hall tho lOp. e, 28 to (jO+ inches. lIetwy, coarse, grauulu.r clay ltlOiUed alld sircu.ked red yellow and light bluish gray. METHODS OF EXAMINATION The methods llsed in pl'oeessing the soil samples wcre essentially those in general use b,v tlus Di\'islon. They hu,ve been described iil detail ill previolls publications flS d t.ed below, The soils were nir-clrird ill the laborat.ory before' the lahoratory "work wus done. TIJC mechnrneni an a Jyses wero made by the pipl'tte llletilOu descl-ibeu by Olmstead, Alexander, and Middleton (33). The pipette method requires the 1'(']\\oY3.1 of orgnnic matter by hyd.rog-('n peroxide in the pretreatlllent of tile sample.. The approximate pel'centnge of organic. matter by this methocl is more rl'liable if it. is gren.t.cr tlmn 0.4. rfhe pH valucs of the soil were determined by the hydl'ogpn-eleetrode method described by Builey (6). Some of the pH determinu,tions were checked by the glnss-e\ectrode method. A suspension of the soil wu,s agitated by a, strenm of ('arbon dioxide-free ail'. The content of soluble snIts in It known weig-ht of soil Wu.s obtained from a. lO-to-l water extract after eYH.pomtion and ignition to dullretlness. The c.hellucal lllul,lysN; of both the soil nlld colloid were made a.ccording to the procedure outlined by Uobinsoll (36), 'who has ada.pted the methods for rock analysis described by Hillebrand (20) to the PIWPERTillS Ol!' NEW ENGLAND AND PIEDl\IONT SOILS 11 analysis of soils. The organic matter was determined by the com bustion method described by Alexander and Byers (1). The amount of water vapor absorbed by the colloids at 35° C. was obtained by the desiccator method described by Robinson (35) and by Middleton (29), In order to increase the probable accuracy, the determinations were made in duplicate and the results averaged. The colloids were extracted from the soils with the aid of a super centrifuge essentially as described by Brown and Byers (9). No dis persion agent was used except as noted in the tables. The colloid from an adequate amount of soil was dispersed in 3 gallons of distilled water by means of a mechanical stirrer described by Holmes and Edgington (22) or, if necessary, by hand rubbing. 'rhe suspension was then decanted into sufficient water to make 10 gallons and centrifuged at the rate of 17 seconds per liter at a speed of 17,000 revolutions per minute (diameter of bowl, 4 inches). The colloid, still in suspension, was collected on a Pasteur-Chamberland filter, and the filtrate was used again as a dispersion medium for the sediment removed from the centrifuge bowl. The process was repeated foul' to six times, or until an a,dequate l'cpresentative supply of colloid was extracted from the soil. Very few of the colloid pnrtirles exceed O.3jL in diameter. The extl'l1cted colloid sample in gross is presLUl1ecl to have the same composition throughout. The composition of the individua.l partides may vary somewlul,t (9). The data are presented in separate tables with a brief discussion of each. Certain derived data have been segregated. In these mag nesiulll, calcimll, potassium, and sodium oxicl.es only are rci'ened to as bases because of their particular significance and importance in soil development. In calculating certain derived elata, the perc-ontage of each consti tuent is divided by its formula. weight. These quotients represent the relative number of formula weights present. The number of formula weights of one constituent are cOlllpared to the mmlber of fOl'mula weights of other constituents as ratios. The dpl'ivation of other data is noted in the tables. In this bulletin the colloids nre assumed to be ehieflv one or more complex amphoteric alumino-silicic acids. A part of tl~e hydrogcn of these acids is replaced by bnses; a pttl't of the hydroxyl is doubtless replnecd by inorganic aeid m(licals. For the sake of simplicity nnd unifonuity, however, no nccOlmt is taken of manganese, titanium, sulphur, phosphorus, and other possible replacements in the ulmnino silieic acid complex. In n few colloids they lllay be signifielmt, but it is doubtful if they are more concel'l1cd with the inorganic than the organic portion of the colloid. Because of their dubiolls :function in the colloid complex they are omitted from the calculations. .... ANALYTICAL RESULTS BRASSUA SANDY I,OAM t The Brassua sanely loam is the most northerly of this group oI soils. As might be expected, it is ~L typical Podzol; the hleueJlC'd A 2 lay('l' is sharply defined, the iron nnd part of the organic nuttter al'C transIenccl to nnd weakly cement the reddish-brown B layC'J's hcltm'. It is of special interest becuuso of its association with other soils whose Podzol morphology is not so sharply defined. Intensive laboratory 12 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGlUOULTURE studies of its physical and chemical properties have furnished an e},,1Jlanation for the differences in color, texture, and other morpho logical characteristics of the various layers of the profile. The mechanical analyses, given in table 1, show the distribution of sand, silt, and clay in the profile. The stony character of the lower horizons, so characteristic of most of the glacial ill·ift soils of New England, is not indicated in the table. Like the Beckett, re ported by Anderson and Byers (4), the clay and colloid are concen trated in the BI and B2 horizons in intimfLte association with the soil organic matter which has colored these byers. Very little fine material has moved lower than this zone of concentration. "Nithin a dept,h of 19 inches a sharply defined Podzol profile has developed. TAm,}] l.-l11echanical an(11ysc,~ of Hr(/"s.~lla sandy loam 1 ~- - -~~ -:-- ~-:.-- f I . Fine \PrJ' Coarse 1"1'\ NlmlTl S IIlri fino BilL, I('jay. Colloid, Or~anic Sample No. Hori.ji Dc tIJlgr.li:~~l. s!lIJlI. saud. '02"': sand. 0.05; 0.00"- 0.002-0 matter zon ·11 2-1 1()~5 0.5-0.2ii 01 0.1- 0.000 0 mru mDl by , , mm llUll lIllll In"r.n g~~ llllll il202 ______I___L~I - ___I _ 1- __ - I i I hI. Pcl. Pel. Pel. Pel. PCI.) Pel. Pcl. Pel. CH3L.. _. __ .. A, 03 5.,1 13.a 13.0 31.:! 1:l.0 17.4 <1. 2 La 0.7 ('1439•.. __ •• ___ _ III 3·4 ~. 2 10.1\ 13.0 2/;7 7.7 11.I 8.7 5.1 15.4 ('1440...... _. __ B, 4 !J 12. :1 2:i. -; Hi. J tt I) :i. 5 I n.4 7.4 1.8 5.1 ('1441.. ...____ .. _ J31 9 ~ I!J SoT> 21."1 IS. I 21. 7 10. () la.1i 2.1 '"I 1.0 C1442.. .. ····_~··1 (' lin &.2 10. \J ].1.0 I aI. U HI. () I 1:1.5 2.3 .0.~ I 0 - --~~- 1 Analyses made uy '1'..M. Hhaw Rwl E. F. 1\i iles. Certain signifieant variations in the cll('lIU('ul analyses shown in ta.ble 2 have an important relation to the transloc:ttion of material iu the profile. Analysis of the material of the Ao l:tyer is included in this table only. This sample of partially decomposed organic matter is comparatively free from. soiL But the quantities of silicn, alumina, nnd titanium are more a1l(l the bases much Jess than usually present in decomposed pine needles. Some of these constituents mightl have been carried up from the nUll Nul soil propel' to the organic ]~lyer. TART,]il 2.-- Chc'IIIic(l1 (1T/f!I?Jse.~ of !-Jrf/..~8Uf/. sanrl1l1oatn 1 ---r-----· ~-.. ,-~--.~,~--- --1------;-~-- Sample H ori· No. I zon D"plh I Bio, 11'~'()1 IAbO, I ~ll';() ('nO I 1(,0 I;-;'11,0 i 'J'j(), i ~lnO 111;.hn pc:r('l~1 j pcrrrlllji Pcrr~ll jPcrrnt.' Ip;;;;,; ;;;;r-;;;! p~'rcl'1~t :PeTro!! IPerce lit .,0 ,~.o. O.IS u,n 0.000.1" 0.0! 0.0,) 0.0,0.001 0-3 81i.70 Lan r..(J2 .J.! .701.01 1.3·t LIS .02 3-4 62.17 1.77 n.ll! .28 I.ll .U8 I.SH .H2 .(J.! 4-0 67. Oil 3.44114. 4,; .·13 J..J7 J..JO 2.:)2 .74 ,05 II-ID 75.08 2.50 ll..,7 .57 1. OS I. oS 2.74 1.·t2 . or. 19+ 77.11 2.72 1O.M .G! 1.00 1.52 2.70 J.22 .10 _...... 71. ,10 ,J. ~ 1 II. 09 1 1.1i2 1. 'Jlj 2. a9 2. 2;' . Gl . OS I Analyses made hy G. ,r. Hou~h (except (' f..j·12A). • CO, or tbe carbonates . • Determined by comhust.ion method (CO.X0.17J). , Determined by E. n. Dailey. 3 Determined by T. n. narris. PROPERTIES OF NEW ENGLAND AND PIEDMONT SOILS 13 The analysis of the soil propel' reflects the podzolic character of the profile. The Al layer included in A2 is mpresented by a thin band, too small to sample. The A2 layer is sharply defmed and bleached to light gray; silica for the most part remains, but iron and tLlumina have moved to the B horizons. Most of the eluviated organic matter has peDetratec1 only as far as the BI layer. Loss of magnesium in the profile is great; of calcium and sodium, slight; of potassium, about as e:ll..1)ectec1. This relationship has been noted by Follett-Smith (17). It seems probable that these variations in the secondary elements of the soil are explained by the composition of the felc1spathic com ponents of the parent rocks. Trisilicn,te feldspars, largely potassium and sodium, l1Owever, are relatively slowly hydrolyzed as compared with clisilicate feldspars (2) relatively high in magnesium and calcium.. The percentage of the bases in the pebbles from the 0 horizon is typical of an average granite. As compared with soils in less hmnid areas, the soluble salts are low in all parts of the profile; but in those layers where they are relatively high, the organic matter is also high. Doubtless the organic matter retains the soluble salts in spite of the free movemen~ of water through the sandy profile. The chemical analyses of the conoid of this soil are presented in table 3. Included in this table are the percentages of colloid extracted by the supercentrifuge for comparison with the percentage of colloid sho\"11 by mechanical ann,lysis. The amount varied widely; in one sample more colloid was extracted i;hn,n is indicated by the mechanical analysis. In this sn.mple the totn.l quantities by the two methods are, however, only 0.5 n,nd 0.0 percent, respectively, of the total weight of the soi1. 1,1.1 { . .. & TAnLE 3.--Cfhc11licalanalyses 0/ FJrasSIIf!. .~and!lloa'/ll. r:olloid Hat" pi!' - K,O Nn,O 1';0. [Jorizoni-ll(,Plh-I~:oJ~~id ~io'l fo'e'(~I-'~~I'O' '-:[1-(O---c:o 'riO, 1l'Hl'tl'd ----- .. ---- __ 1__-- ___- .. ______ J'(r('(111 ('H3L ____ 11l~·ltc.~ Pact'll' Pen'ful P,'rCl'nt Percfllt PI'Tt'c·,,1 Perct'llt Perce1lt Percent A2 o a ~rl 41.45 4. ·LlI 20.1·1 ('Hm _____ Il, O. U5 O.:li l. :!l O.a5 2.G!! 01440.. ___ :1-·1 10 12.nB ,1.40 la. Hi .m .:H .:17 .17 I.:l2 Il, ~-1) !!l 11. Ii) ('1441. ____ i.ao !H.4U .0Tl • ~L .2·) .1I _49 Il~ I)-J!) 120 10. Un 7.H2 C'HI2. _ 2U.~1 .50 .40 .no _IS .55 C J(J+ 50 31. 02 O• .1\1 28.23 1.93 .n:l 2.28 • UO .55 Snllllllt' No. Orgunic UOl'izon Depth MilO SO, 11111!- 00,' N' ter 11 ------01438______._ IncheoY Pacent PI'Tcent Percent Percent Pacf/il Percent Percent Percellt 0)0\3o ______O-:J O. or, 0.49 O. I:J 2S.05 IIKI. on 22.42 0 0.89 01440______•••.. __ . a.....t . o:~ .47 • :t!! ml, fiO 011. UO 49. OS • 05 I. 48 01441. ______4-0 .01 . ar. .2X 55.20 100.4X ao. (ir. 0 J. 17 01442__ . ____ .. __ tHO .01 .71 .2[) 4a. a5 IOI.I/i 20.20 0 .76 I!i+ .12 .!I!) .ttl 2a.(;.J 1110.10 12.20 0 • .12 1 Det.ermined hy (·omhust.ionlIlct.hod ({'(J,XO.-l711. , Determined hy 'f'. H. 1Iurris. 'CO, or tho mriJonntcs determined h~' W. ]\'[. Nol"". The chemical anulYRcs of the colloids present a more complet.e picture of the results of Podzol profile deyelopment than do analyses of the soil. The colloid or t.Iw most. aeiel, bleached A2 layer apparently has not undergone complete altcl'Il.t.ioll. Tbe relatively large amounts 14 TECHNICAL nULLETIN (i09, U. S. DEPT. OF AGRTCUL7URR of potash and alwlliua may indicate the probable presence of in eompletely decomposed feldspar and mica (muscoyite). Obviously iron oxide has been transferred from the A to the B horizons. The lower percentage of alumina in the B1 horizon does not indicate that no such transfer has occlll'recl. On the anhydrous-inorganic basis the relative percentagrs are 32.6 percent in the Bl horizon and 28 per cent in the A 2• Titanium, like silica, of course rrmains relatively high in the A2 horizon. The eolloid of the Bl layC'r has much less alumina than the B2 and Ba horizons, but mn,rkedly more iron o:.\.-ide and orga,nic mattrr. The iron probably has brrll carried as a, ferrous humate and dcpositC'cl as ferric hydro:.\.-ide and humic acid. The B2 and B3 horizons and, to some C'xtC'nt, the C, haye accumulated both iron o:.\.-ide and alumina from layers aboye, but silica and many other constituents haye to some extent beC'n removed altogether b:v percolating water. These Telatiolls are still more e\'ident if the analyses are corrected [or the ignition loss, although tlwy arC' 1I0t altogether concealed by tlle presl'nce or organic 1110 UC'r nnd com bined water content of the colloids. The derived data (table 4) for the colloids present more clearly certain relationships thnn do the analyses themse]yl's, 'rhe colloid of the bleachl'd layC'r s1l0\\':'; the high silicn-sesquioxidl', silica-iroll o:.\.-ide, and silic:1-ulumir1ll, rntios chn..met('ristic of Pod7.01 form,ttion. The low ratios for the lowrr stmLa indicate the t.ransfpt, of iron oxido and of alumina, from tllC A horizon to a 10w(,I' 10v('1. The mnximum yalue for tho rl'nie oxidC'-nluminn, rntio indi('nt('s proeipitation of ferric o:dcle in the HI hOl'i7.0n. Tile. varying of their ratios is indlen.tin' of selective Temovn I or ([('position of tll('se constituents. The exceed ingly low silien-sesquioxide and silien-nlumina mtios indicat.e n,n extensive brl'nking down of till' Jllinerul eomplex, und the geneml relations illdicntc the pr('s(,lIce of frC'o iron ilydl'oxid('. This condition of the iron and t.Iu:' ullc('ltnint.v of the (kt<'l'minntion of the orgnnie mntter 111 a ke the wnt<'l' rntios of kss vnlue as a. mea ns of estimating the ellm'neter or the nlumino-siliente ('omplC'x than is t.be cuse with colloids which con Lain Ipss organic. mntt(,l' und in which the prl'sence of iron o:-.-ide is (widC'nL Npvertill'less it, is or intprest to eontrust the formula ratios of til(' A2 nnd ]32 horizons. A2, 2.99Si02 • (F('20a,Al 20 a)·1.GOH20; 3.41Si02 ·AI20 a·1.82H20 B 2, O.68Si02 • (Fe203,A1 20 3)·3.04H20; O.81Si02·AM)a·3.G2H20 TAm,!': 4.-Derived tia/a: TJrassua sandy loam colloid FOrilluln rutio Horizon Ill'ptll ~iOt Ri(l, FlltOl -V~; Im'lie.. ('Has .••••...... ,\, 0-3 2,00 201.15 a,41 n,l,11 ]4, an ('14311 .•.."" ." II, :H 1.05 2.05 l. 03 ,';52 14, Hoi CI0I40 •• ". 'JI, 4U • (is 4, HI .HI .187 19.95 (,144L.,: 113 O-H! .0:1 7,50 , U(i ~ 127 9.79 Cl·H!L._.~_ . (' 1iJ+ J.5a KfAI LoB .210 5.2.'5 - I U. ,10 .2·15 12.79 ~ 1.7a Profilo UV(lro!!i' .-I •• I "_. U21 ) I 1 Oxidl1S of IIlUg-lte5itJlIl, t'all'illlll, IJ(Ituso;itllll, awl :-;~HliullI. PRI)FKRTIES OF NEW BNGLA.l.'iD AND PrElnroN'.r ROTL3 15 TADL}J 4.-Drrivl'd rlala: Brussila sa.ncly lam//. colloid-Oontinued Formula ratiu ('-om Comhined 11 orizoll ])('pth hilled wale-rot H,ll , wuter 3 the soil AbO; flt'iu I ------l'iT('t'l,l J'lU('t'lll ('1438. ______•• _. , Illcil,'" ! .A2 O-:J 1.870 I. GO 12. flO 1.8~ 5.(;:1 8.:15 ('1430..______..... i HI :J-l .a7:\ ~,hl 7. OJ ·1.:1. U. III I ~.~ ('1·140 ....__ .._..... , HI 4-11 .224 :to-l HI. 80 a. It! H.. ;15 , 21i. OS CI4·\I...... 11; 9-19 .287 2.~U 26,40 a. :\;; 17. },-) 2:1. H·I 1'1-142 ...... W \\1+ .708 2.1G 12. ()U I 2. (i:~ II. :1;, I If>. (K) .- I _.- ,~- --~ .....,...-- I ------PrnfJll' ~!\·prar(>_. .li\l2 2 rlf) 1 l!i ~jJ :t Hi 11 tl2 1S.7i i r ____ • ___ 4 __ .. --~------~---- - :! ""tlt(·C' o[ cmuhinn.tiott Vius wab'r N,uiVnleut of ttl..• l.HLSt·~. 3 Ignition loss less the orgnnic IlJuttor~ t \\"uter of t'OIubioution plus 'Vntcr equivnlent of tilt' bUSllS, corn'('tl't.i for organa,- Ilmttt'r nod carbvwtc content. HEIlMON SANDY LOAM Like tile Bmssua, this soil is n Podzol. It is of particular iuterest because of its grogruphie!1111NLl'lIess to the Bmssun. The profile is deeper 21ml the horizons are less well defined; lH'Yl'l'thele>'s tbe gra.y layer and other Podzol cllll,T!1cteristics am easily recognized. Tbe ml'chnnical ann,lysE's are given in table 5. ,Yhile il;c cOlltl'nt of silt t and Ch1Y is sOllwwhn,t gl'eatet' in t.he IIermoll sandy Imlln, the l1ul.xim lUll day concentration, in the Hi horizon, is but 5,5 pl'rCt'nt, while in tbe HmssulL the ma~;,mulll cIny content is nlso in the Hl horizon and is R,7 pt'l'ccnt. The 1A'~lUl'nJ diIT("'l'll(,('S l)('tWl'{'ll tiwse two soils, while prohably due chiefly to difl'{'l'eIwes in the IHLrellt rock, are in pn,rt a result of tbe difl'l'l'elwl's in plc\'ution and in vegcLative l'OY('r under whit'h tlH'.v hnsc dcYdolWd. TAHl,e f).-·.11echanical (l1wlys('s (lj IJermon .~andy loam I ~~-.---;-- i: ;\[('111' Fi e Y(·ry I . I Fiut' (~(I~lrSll uln "ll~ti tiut' SiH. ,,·lc II . I Orgnnic i P(II II p '1r:.' 0.01.- \ ,ll;. 0 ~~H., matter. IIOfl~ g:rnve1. $nnil :-.und, ti snnd, 0.005 O.GO,....u hy 7.1111 I " ~ i HI.5 0.;,... '6"1 1I.1· u.m.-o I t mill min () '15 JIll'U 0.U5 mm IIUII HIIH IhO, UUIl Hun ..------!.. ------,---'-- III. Pel. Pel. Pet. J'd. 1'cl. Pel. -I· Pcl. Pel. Pct. A, U 1 .1. 5 !J 7 Il. \) 21. U 1:1..\ )0\.2 4.1 1.U 20.8 A, J.;, .1. 0 \·1.·1 ]f•. U ~S. II 15. ~ 15.1l ·1.2 ~. 0 2.3 HI IH5 3.4 1l.U II.S 24.1 15.~ !!O.·' 6,!'i :l.li 1.0 Til 1;,..2·1 5.0 JI.S la.a ~lj ..'i IG.R 22,1 2. ti ., 1.3 II, 21·32 5!1 la.O 11.2 2S.~ Js.~ 17.1> 1.li .:J .4 I (. I 3~-r ·1 4 I:\. 0 J.J. \) :11. h, Ib.•1 I lIi.·\ ~.\) ,h .1 ------'-_.--...... - ....- ....-~.--.---'--.'---'-- I AnulY$M 1I1UU" hy 'I'. AI. ~huw und E. F. }'liI~". The ehemical I1nnlyses of the Hermon sl1ndy loam ure given in tltble U. Cl'rb1in difrcrences betwl'(m these l'N>uHs and thos0 fount! [or the BI'as:::'LH1 sn.ndy lOltm (tnble 2) ttppen,r. Thpl'l~ is not so much organic m!Lttpl' in this profile, althougb it Ims penptmtca to a greatpr dppth, Ncitht'l'is the 11.cidity so gl't'at. 1Iol'(~ thorough len,rhing of the htyers of the Hermon profile which arc low i.n orgtLnic matter is evidenced. by t.he mo)'e eomplcte removal of soluble salts 1'1'0111 them. As in thl' Brasi'H1n" the siliea J'('llIll.iIlS in the A2 horiwn; there hn.s beell considemble tl'lLllsfcl' of orguui.c limiter to the Hi llorizou; fLlHl til c 16 TECHNICAL BULLETIN 609, F. S. DEPT. OF AGRICULTUm;; sesquim.:ides have accumulated in the Bl and B2 layers. Likewise, magnesia and potassium haye been removed from the upper layers, but an equivalent loss (.f sodium and calcium has llot taken. place. Percentages of calcium u,ud sodium Me higher u,nd phosphorus lower in the parent rock as compared with the soil profile. This appu,rently accounts, in part, for a slightly 10wer u,cidity in the Hermon as com pared with the Brassua. Undoubtedly, the rocks and pebbles by slow alteration. are al"'4isting the recently introduced shrubs, brambles, and weeds in mail1tnining tlw supply of bases in the soil. '()rt!t1uif· Smllplr l~nitifln ,/",1,,1 I mal' ('0," :\3 Xo. i III~:; I !I'r" i ' , 'I ! I ,"~l--- /urli(!f ))'f{'f'Il/' }),'Cllll, jJ(rrtllL /Jrrrillt j'(rct'lIl, IJUrllll, li(n'eul P .. JJ.11l"!' f.)trCl'1lt C'I4Z1 II I lUI!!: II. iii I !!:l.!!" Ion. II : ~L :11 : II i II. ·I~ I :HiO :l. \I CI4:\~ I 5 I .0:\' Tn"'.' I :\.:\~ IIIU.l',\ !U.·I i U i .ll., 15U .1. 0 C'I·t:I:! fi Ifi t • ua I • nt !I, {II-; : lIlli tIli ti. fill ( II I • 1~ !?Otl I ,1. X ('14:14 Jf,- ~I . II:! .II.!,:I. ·11 IliO IJ(I l. 'ill I II I . n·I' II~I .I,!l ('14:15 ." :!1;{!.! .11-1 .lIIi, I. II HH ,Iii H \ (J' ~()1 150 fi.5 CJ.1:15A. a:!+ .OJ .01 fili {i!/. lili . IIi I 1I i U 20 rJ.7 ('1·1:I"fl , .01 .17 t1;; Iilil. Ii ! J Aua1y~~'iS made hy (Hell EtI/.!iucloli. .f.1JYl'omhu:-;rion IlWtlli1t1 \('{'2XO.47J). 'Annlysb mnel,' h;' O. J. HUll!!}). ~ ('02 or tJlU eurllorlut"s. , Determined hy '['.ll. limrb. G l)l'l~rmiucd by g. Lt. lInilry. TIle chemical luw.lYfles of the colloid ure given in tiLbJe 7. The results are those eiHtl'll,eLt'I'istic of the Podwl pl'Ofilc in tllll.t the sillctt remains high in the A horizolls wbile there is :I. lluLl'ked illC'l'anse in one of the sesquioxiti{'s ill the 13 horizons. The ciifl'el'ClIces lwtweeu the colloids of the Hel'lnon H.J1d those of the .BrnsslllL n,re lIot llHLrked, though there nt'e many difJ'cl'enees ill detail. Perlmps the most, striking difl'erence is in tIle titu.nium content of tbe A2 horizon. buth the Hermon nnd BmssulL colloids Itlwe n, very lltn.lieriil.l titn,niuLtl coutent, particullLrly the .1'1.. horizon. The dn.tlL do not indietLte whether the titanilun consists of hydm.ted forms of the ll1inel'flls present in the parent rock or of the iinely dividpd minerals tlH~mspl ves. The St1111e rch1tions bctw(;cn silictL t the scsq uioxities, and waLPt' she Wll by Podzols in gelleral n.ppen.t· ill the IJennon colloids iI.lId tWO qUlLntitatively expressed by the dCI'ived tin,tlL given ill taule 8, PROPERTIES OF NEW ENGLAND AND PIEDMONT SOILS 17 TABLE 7.-Chemical analyses of Hermon sandy loam colloid Sample Hori- Oolloid Depth ex· SiO, Fe,O. AbO. MgO CaO K,O Na,O '1'iO, No. zon tracted ------111ches Percent Percent Percent Percent Percent Percent Percent Percent Percellt 01431 _____ A, 0-1 rill 25.08 7.15 14.69 0.49 1.34 0.42 0.12 1.26 01432______A, 1-5 15 34.05 8.57 16.39 .80 .il .32 .12 4.04 01433______TI, 5-15 56 10.24 7.82 24.97 .22 •i5 .14 Trace .5 01434______B, 15-24 180 14.04 8.90 31. 42 .n .25 .33 Trnce .37 01435______B3 24-32 140 18.65 7.12 33.86 .50 .71 .30 28 .17 CH35A____ (' 32+ 42 22.38 7.00 34.50 .98 1.05 .88 .49• 1 .31 IIori- Ignition Organic SamploNo. zon Depth MnO P,O, SO. loss Totsl mat- 0O,' N' ter II ------01431.______Inches Percent Percent Percent Percent Percent Percent Percent Percellt A, 0-1 0.02 0.95 O.:li 48.10 90.97 43.12 0 2.03 01432______.. A, 1-5 .O:l .50 .24 33.35 99.99 25.96 .08 1.50 01433______. TI, 5-15 .02 .57 .22 54.80 100.29 39.30 .Og 1.85 01434______B, 15-24 .O? .52 .28 44.65 100.89 25.34 .07 .71 C1435______.• TIa 24-32 .03 .95 . Ii 37.25 100.29 10.30 0 .98 C1435A ______.-... C :12+ I .16 .99 .11 30. sa 99. /)8 13.50 0 .73 , Determined hy comhustion method (CO,XO.4il). I Determined by T. H. Harris. , 00, of the carbonates determined by W. M. Noble. TABLE B.-Derived data: Hermon sandy loam colloid Formula ratio IHorizon I Depth Sumple No. SiO, SiO:! SiO, Fe,O. Total bases , ------1·--- Inch" 1431.__ ...._••• ____ ._... A, 0-1 2.21 9.32 2.89 0.311 1l.82 1432•• __ ..._•• _____ • __ •. A, 1-5 2.71 10.81 3.62 .335 15.51 1433•.•••____ ...... III ft-lli .58 3.48 .70 .201 8.36 1434______...... __ ... n, 1[,-24- .()\ ·1.19 .70 .181 21.85 1435 _____ •• __ ...... _._ Ih !l4-32 .82 6.89 .94 .136 0.46 1435A ______.••. ___ •__ o 32+ .07 8.48 1.10 .130 6.16 1.32 7.19 1.67 .216 11.8/1 i Formuln ratio Com Oom bined Sample No. Horizonjl)"Plh bined water or n,D' H.O' wilter' the soil AbO, acid' ._------ ll1clla Percenl Percent 1431 •.••••••••.___ .••• A, 0-1 1.304 1. ~9 7.15 2.22 4.98 1O.1l 1432...... A, 1-5 1.295 2. OIl 8.34 2.711 7.311 10.110 1433...... 13, 5-15 .11l3 :1.01 18.04 3.63 15.50 26.38 1434..____ •. __... __ ... 11, 15-24 .215 2.Ui 19.50 3.54 W.31 20.15 1435••••_____ ... __ .•__ 13, 24-32 23') 3.M 29.70 4.05 23.52 27.88 1435A •.••• ____ ..., __ _ ---C ---'--'32+ ----.31Xi ,-----:1.17 ----27.72 ----3./10 ----20.6:1 --24.35 ~691 2.75 18,·11 3.30 15.25 20.96 I Oxides of magnesiuIJl, calcium, pOLUS1·HulIl, lUlU sodiuUl. 2 \Vater ofcombinntiou }l\US wutt!f equivalent o[ the- bases. , Ignition loss less the Ilr~unic llIutter. t Wnter of combination pluswllter equivnlent of the buses, corrected lor organic matter lind curboDSte content. 18 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE The ratios of various constituents with respect to silica testify to extreme podzolization in spite of the .diffuse profile morphology of the soiL They define the horizons sharply. The coUoid of the.A horizons has lost sesquioxides by eluviation to the B horizo::lS. The silica sesquioxide and the silica-alumina ratios of the A horizons are ap proximately two to five times those of the B. The movement of iron pxide is certain but not pronounced. Undoubtedly silica has been removed from the whole profile by drainage waters. Debasing of the colloid is most complete in the B 2 1ayer (table 29). Removal of bases from the colloids is probably an effective cause of deposition of sesquioxides in the B horizon despite the low pH values. As-in other Podzols, the water-sesquioxide ratios are somewhat inaccurate. Silica, however, is low if the wu;ter content of the colloid is high. This inverse relation is shown by the silica-water ratios, which areJow in the Bl and B 2 1ayers. The combined water of the soil acid is sbout two and a half times greater in the Band C horizons than in the A. The maximum quantity is 27.88 percent in the B3 horizon. High values for the combined water of the soil acid are apparently common in colloids of the B borizon of the Podzol. Itis believed by the writers that the greater part of this water enters into the constitution of the alumino-silicate complex. Such a complex is indicated by the fonnula ratio O.70Si02.Al20 a.3.63 H 20 of the Bl horizon. Iron hydToxide loses water more readily than alumina and doubtless does not exist in soils subject to high tempemture or prolonged drying. When the iron content of a complex mineral is separated from the silica:te com plex, the hydroxide produced may be expected to lose a part or all . of its combined water. Better aeration and high temperature at a slightly lower elevation than those of the Brassua may account for the difference in color of the two profiles. Undoubtedly it is partly due to the difference in the character of the vegetation. It cannot be doubted after a review of the evidence p~'esented here and elsewhere that the Brassua, Hermon, ~md Beckett Podzols possess profiles whose chemical and physical characteristics are markedly similar. In fact, the chemical data alone would place them within this group. Tbe relationship of the three in this respect is close in ...., spite of slight differences in geogra.phic position, morphology, and climatic and vegetative variations. GLOUCESTER SANDY LOAM The Gloucester soils belong to the Gray-Brown Podzolic group and are important soils in New England and as far south as northern New Jersey. They are of special interest because of their wide distribution and the similarity of climate, vegetation, and parent material respon sible for their development. Furthermore they offer an interesting comparison with the Podzols whose data have been commented upon. Two widely separated profiles have been selected, one from near Medway, Mass., the other from near Rockaway, N. J., 150 miles farther south. Both are developed on glacial drift, although in Massachusetts the drift was deposited by the last ice sheet and in New Jersey it was deposited by the first. The morphology of the New Jersey profile is not sharply defined. The lettered horizon designations in the New Jersey Gloucester are used with some hesi j tation. , PROPERTIES OF NEW ENGLAND AND PIEDMONT SOILS 19 TABLE 9.-llfechanical analyses of Gloucester sandy loam 1 FROM MASSAOHUSETTS Very Fine Ooarse Medium Fine fine Silt, OIay, Oolloid, Organic Sample No. Hzoonri- Depth b'lg~lel. sl·a~d.5· sand. sand, sand, 0.05- O.OOS-{) 0.002-{) matter lDm ~ 0.~25 o~i:-m g:~5 ~o: 'mm mm byH,O. ---;::- Pct. --;;:- ---;:;:-1- Pct. ht. Pct. --;;:---;;: 0585______\ A, 0-2 6.0 5.4 5.3 12_5 ::!Hi. 8 29.6 7.7 5.2 16.5 C586-______1 D, 2-3 3.4 S.5 8.5 ZO. ~ l~. ~ 27.3 i.6 4.6 4.3 0587-______I D, 3-15 4.3 O. () 8.9 18.2 lb. I 31. 1 10.9 7.5 .7 0588______D, 15-30 5.6 0.5 8.71 18.61 17.8 33. 1 6.1 3.4 .3 0589______C 3(}- FROM NEW JERSEY 099L______0902______A, 0-3 5.4 11.4 8.2 14.6 13.6 23.5 12.4 9.3 g.5 0993______A, 3-9 6.5 12.9 10.4 111.8 15.6 22.6 11.2 9.2 . i 0904______D, 9-2U 6.5 13.9 11. Ii 20.7 16.3 21.2 9.4 i.l .3 C905______B, 20-30 8.1 14.3 11.8 18.8 15.5 22.9 8.5 5.3 0 :lU-r,o la.l 21. 7 17.8 6.4 C900______D, B.O 16.S lti.l 5.1 0 lIj 5O-1JO 11.0 16.7 11. II 18. 6 I 14.0 I 18.0 10.0 8.3 0 ------_. 'Analyscsmnde byT.l\L Shaw lind E. F.l'vIiles. The mechanical analyses of both soils are dIsplayed in table 9. They give DO hint of any marked transfer of material within the pro files. In New Jersey the material from the Jerseyan terminal moraine (oldest drift) is a little sandier than the youngest drift in Massach'l setts, and consequently the silt fraction is greater in the Massachu setts soil. The New Jersey profile is much deeper. No significant variations in the colloid content are observed; it is, however, low in both soils. There is e\-idence of eluviation of the colloid from the first two layers of the Gloucester soil from Massachusetts and con sequent deposition in the B2 layer. This is DOt observed in the soil from New Jersey. Mechanical transfer of material within the profiles of both soils is inconsequential, although they both possess excellent underdrainage. TABLE lO.-ChemicaZ analyses 1 of Gloucester sandy loam FROM MASSACHUSETTS Sample No. ~~~- !Dt'pth I SiO, Fe,O, AhO. MgO C"O I K,O No,O ITiOI MnO ----1-----;;;;;;;' Percmt Percent -;;;;;;.;;; Percent Percent. Percent Percmt Percent Per.em Oli&~ ______A, 1J-2 02.00 2.01 7.4:1 O.r,o 1.41 1.511.400.55 0.06 0586______B, ll-3 75.1172.708.70 .40 l.o!! 1.75 1.55 .66 .06 0587______0588______D, a-15 70.62 3.07 11.03 .50 1.62 LBO 1.80 .67 .07 B, 15-30 78.96 2.54 9.94 .33 1.94 1.92 2.04 .6g .06 0589-._.__ _ o a0-40 79. 39 2. 43 O. 75 .49 2. 10 1.94 2.22 . 114 .07 0589A____ _ Hock 73.40 3.96 12.68 .95 2.02 2.91 2.75 .60 • OIl Organ- Sample Hori Depth so. icmut- CO"j No. zon ter'3 ----1------Inch.. Percent Perctnl Percent Percent Percent Perc",t Percent P. p. m. 0585__ •___ _ A, 0-2 0.12 0.12 21. Oi OU.80 21.10 0 O. 40 39~ 3.7 OS8!!..____ • D, 2-3 .06 .05 0.85 100.11 b.13 0 .12 120 4.1 0587__ ...._ D. 3-J5 .06 .07 2.70 HKl.lO 1.27 \I .04 160 4.5 0588•• _", _. H. JS-aO .06 .05 1. fi4 100. 07 _til 0 .02 136 4. II 0580______o 30-40 .08 .02 .4390.fiO .10 0 0 60 4.0 0580A____ _ 110ck .26 0 .02 100.11 ____ • ______• ______ See footllote~ ut cud of tuble. 20 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE TABLE lO.-Chemical analyses 1 of Gloucester sandy loam-Continued FROM NEW JERSEY Srunple lIor!- 11.],0, MgO K,O No,O TlO, No. zan Depth SiO, Fe,Os 000 MnO ------"------Inches Percent Percent Percent Percent Percent Percent Percent Perce71t Pcrccnt 099L._____ A! 0-3 66.31 4.57 9.44 0.75 1.22 1.88 1.22 0.97 0.06 0992______A, 3-9 73.90 5.02 10.75 .79 1. 41 2.23 1. 45 1.13 .05 099L_____ B, 0-20 n.78 5.28 11.38 1.02 1.35 2.26 1.44 1.02 .06 0994______B, 20-30 74.49 5.50 10.94 1.04 1. 57 2.33 1.65 1.02 .05 0995.._____ 0996______B, 30-50 74.61 5.45 10.90 1.17 1. 79 2.20 1.64 1.01 .07 74.22 11.31 1. 38 2.42 0996A_____ B. 50-60 5.43 1.05 1.86 .95 .08 Rock ------65.75 ! 7.34 13.75 2. i2 3.54 2.17 2.05 .&5 .09 Organ- Sample Hori- Ignitionj Total Soluble No. zon Depth P,O. SO. Joss icmat- 0O," N' salts pH' ter" ------"------Inche8 Percent Percent Percent Percent Percrlll Perc"pl Perrent P.p.m. 099L.____ 0992______AI 0-3 0.14 0.12 13.70 100.38 12.00 0 0.32 250 4.1 A, 3-9 .08 .09 2.79 100.29 1.09 0 .04 125 4. 3 099L_____ B, 9-20 .06 .04 2.11 99.80 .40 0 • 02 105 4. 5 0994______0995______B, 20-30 .06 .03 1. 53 100.21 .30 0 .02 150 4. 6 0996______B, 3()-50 . U8 .01 1. 09 100.02 .10 0 .01 155 5. 1 B. 50-60 .08 .02 1. fiO 100.30 .11 0 .01 130 5. 2 0096A_____ Rock .18 .02 1.34 99.80 .07 0 .002 _.. ---- 1 ------~. - -" I Analyses made by Glen Edgington except 058l1A. • CO, of the carbonates. , By combustion method (OO,XO.4il). • Determined by E. H. Bailey. 'Determined by T. H. Harris. The chemical analyses of the soils, presented in table 10, are re markable for their constancy throughout the full depth of the profiles, except in respect to organic matter. Very few significant variations occur. Magnesium is low in both soils. There is, also, indication of leaching of this element from the A hOlizons of the more southern soil. The lack of evidenee that other elements, many more vulner able than magnesium, have been removed in solution would indicate that such losses are not great. It is remarkable how durable the soclium, calcium, and potassium minerals have been, in spite of easy penetration of both profiles by percoi!1ting water. The soluble salts are relatively low, and the acidity is moderately high. These two facts, in addition to those enumerated above, indicate fairly complete removal of the soluble products of rock decomposition; but rock decomposition is far from complete, as indicated by a comparison of "' the analyses of the soils and their parent rock. TABLE ll.-Chem.ical analyses of Gloucester sandy loam colloid FROM MASSAOHUSETTS • COIIOid/' i Sample Hori ])epth ex- Sin, i Fe,O, Ah(), MgO CnO K,O Na,O TiO, No. zon troeted , ----\--- inch". Perrent lp.erccnt iPcrcenl ~ Percent Percenl Percellt ;;;;;;;; Percent 0585.._____ 0-2 1822.05 5.0415.08 (1.27 0.47 1.08 0.20 0.80 0586______2-3 J5 2i.13 12.25 18.56 ].36 .22 .30 .60 2.23 0587______3-15 JO Ii. iO 1a.22 38.20 1. :15 .15 .51 .21 1. 81 0588.._____ lii-30 J7 22.8410.7134.09 1.40 .a9 .83 .·12 2.44 0589..____ _ 30-40 5 38.64 7.2:3 28. 70 ~. H 1.48 2.02 1. 04 1. 54 I~ni Orgon Hori Depth tion 'I'olul CO,, SnmpleNo. zon MnO SO, icmat loss ter 12 ------1------~ Inch c., Percent Percent Percent Percent Pcrclmt Percent Percenl Percent 0585______"___ A I ()-2 n. 05 O. 48 O. iO 54.02 101.50 ·tn.75 0.10 2.36 0580___ ••______TI, 2-3 .02 .211 .:37 37.25 100.55 22.26 0 1.25 0587______D, 27.211 100.98 9.58 0 •all 1~=~g I :R~ :~ :~~ 25. 111 100. 54 10. 02 0 .liO g:;:::::::::::::::; lb' aO-40 j ,00 .na .2a 15. fIfi 100.17 0.34 0 .:17 S~e footnotes at end of tuble. PROPERTIES OF NEW ENGLA:t--rn AND PIEmIOXT SOILS 21 TABLE l1.-Chem'ical analyses of Gloucester sandy loam colloid-Continued FROM NEW JERSEY Sample Hoonri. I Depth 'ICO~~~id SiO, Fe,O, IAbO, ~IrO ('aO \! K,O 'I Kfi,O ITiC, Xo. 1. I tracted :Illch," Percelit Pt;;.CC1~t PCTCe'llt Ip'f;.i"!'t !paCC!ll :PCTC~1It IPercent ;;.::;1 PeTcent CWl...... , Al I 0-3 S _3.00 14.15 __.,OJ 0.,0; 0.31 1.00 0.141 0.75 c992....·--1 A, I 3-9 1:1 I 24.40 15.78 33.27 1. 04 1 .21 1. 0-1 .15 .87 Cn9a...... £1 9-20 24 22.40 17. 29 35. 98\ .90 • 10 . 51 . OS I .84 CU94 ....,•. , 11, I 20-30 Hl 19.78 !4. 1:1 :,0. fiG .l'4 .00 .48 . III .7i C095...... ! £3 ' 30-50 R 33. ,11 11. g,; 3:1.·14 1.1;9, .10 I. 46 .23 .77 C996·. ' n. 50-fit) 20 I :18. fiO, 12.4fi 3t 2~' 1. 7!1 I .19 1I 1.66, .12 ,08 I J , ! t • I I I I i l~lli· , 1Or!!nll' I " Sample No. I l;~~. Depth MnO 1',0. \ SO, , tion ! Tot"l !ic milt· I), CO,, N 2 ' 1 j loss ter I , I ------:----I--I--I--:------!--I-- I I Inch!,s PeTCe1lt !p<'1ce!lllpercf,~t IIP;Tre1l1 \Perce:;~ p~;.cellt 'Percent IPercf1~ CWL ...... _..I ~\I 0-0 0.001 O.tI) 0.'\' ,16.\0 100.28 _".55 0 I 1._2 C992.··...... ··l A, I 3-0 .oa \ .58 ' .2!l ~2,9S 100,64 1l.0ti 0 .38 C993....._...... , HI I 11-20 .05, . (IS .211 2l.4:~ 100.r.5 4.30 0 1 .25 C9!1L...... H, 20-aO .08 .57 1 .21 23.55 100.18 4.0'1 () I .24 C995..,,___ ...... : B, I ao-"o .15 • GIL I .13 1 W.ID 100.12 2.20 0 .17 C996·...... ; Jl. 50-fiO .1S I .50, .03 i 12.701100.25 i ,77 \ 0 .22 1 Determined hy the cumbustioll method (CO,XO.'!71). ! Dctermiuet\ by T. R. Harris. l CO, of the CllrbonBtes determined by W. !vI. Noble . • Dispersed with amlllonia. The analyses of the colloids of both soils, as shown in. table 11, present an entirely difIcrent -picture. The. composition of the colloid is decidedly 'Variable within each profile. These 'Variations are largely obscured in tables 9 and 10 because the quantity of colloid is small. The silica, as usual, is fairly high in the A horizons, which fact becomes more apparent when. considered on the inorganic basis. The sesqui oxides ha'Ve been eluviated to the B layers in both soils but to a markedly less degree in. the New Jersey colloids. The bases of the colloid are low in tIle B layers of both soils, particularly when the high organic content is considered. The acidity (table 10), as expected of podzolic soils, is high. Itis highest at the surface, and decreases with depth. The pH vnlue of the B2 horizon of both soils is about 4.5, which is e ...ridently close to the isoelectric point of a thoroughly debased colloid of this type. Mattson (27, p. 4,83) has found that the critical acidity for the precipitation of colloidal aluminum and iron silicates is close to this value. The two factors are necessarily interdependent. Decomposition of the colloid at the higher acidities during the leaching process l1as undoubtedly favored their frnctional deposition in lower horizons of successively decreasing acidities. The colloids of low base content are flocculated and deposited in the B layers. (See the last column of table 29 and o· table 31.) The distribution of bases offers some interesting observations. As in the Podzols farther north, they are at the minimum in the B2 layer, but they have not been so thoroughly leached from the solum. On this account, magnesium and potassitun are more persistent; in fact, about half the magnesium is still retained by the colloids of the upper layers as comp!1rcd with that in the C. OIl. the other hand, a greater proportionate amOlU1t of calcium has been remoyed from the Gloucester colloids. Sodium has suffered its usual fate, but removal 22 TECHNICAL BULLETIN 609, 1]. S. DEPT. O:F AGRICULTURE is not extreme since a moderate amount still persists in the C horizon. There is no doubt that the quantity and character of the vegetation growing on the soil have been particularly effective in distributing magnesium, calcium, and sodium in the colloid of both pl'ofiles. The behavior of other colloid constituents is not so regular. In a general way, however, they tend to collect in the upper more acid layers, where organic matter is abundant. The association is not clear except for phosphorus, sulphur, and nitrogen. All, or a consid erable part, of these elements are doubtless associated (combined with) the organic matter. -I .. TABLE 12.-Derived data: Gloucester sandy loam colloid FUOM MASSACHUSETTS F'Ofmuln ratio Combined ~ SnmpleNo. Horb.on Depth 1Combined 1 wuler oC o SiO, SIO, RiO, H,O' [120' 11,0' wuter' the soil '"d 1:'10, !'e,O, I SIO, lleid' t::l }'e,O,+AhO, }'e,O, AhO, AhOl 'rotnl bnses J 11,0' Fe,Q,+AhO, Fe,O, A1,O, ~ 1--1 1--1--1--1----1--1 1--,--,----,-·- t;j 0585______lnche& Percelit Percent Ul A, C586_____•••• ______0-2 2.00 10.38 2.48 0.239 6.87 1.133 1.77 0.17 2.10 4.87 11.60 D, 2-3 1.74 5.80 2.,18 .421 8.02 .511 3.41 11. 53 ·J.85 14. OI' 20.48 C587______. _____ • ~ C588______• ______B, 3-15 .64 3.56 .70 .221 6.56 .286 2.":1 12.45 2.75 17.71 20.56 C589______.. ______D, 15-30 .93 5.66 1.12 .108 6.46 . ·118 2.22 13.55 2.68 15.20 18.31 C 30-40 1.97 14.19 2.28 .161 4.70 .094 1. 98 14.20 2.29 9.22 12.44 2: t::l Profile a."ra~e------==1______1. 40 7.94 1.83 .248 6.72 .068 2.32 12.10 2.95 12.42 10.66 :;J t .!--.~-.-~ tj !>' , Oxides oC magnesium, calcium, potllSslum, lind sodium. , Water oC combination plus water equivalent oC the hnses. o"" • Ignition loss less tbe organic matter. ~ , Water oC combination plus water equivalent 01 tbe hases, corrected Cor organio Il!att.er and carhonat.e content. 1-3 Ulo 8 Ul ~ c,.:) 24 TECHNICAL BULLETIN 609, U. S. DEPT. O~' AGRICULTURE The derived data in table 12 offer quantitative evidence of frac tionation in both soils. The silica-sesquioxide ratios of the colloids of the B2 horizons are extremely low. For the B horizons they are somewhat lower than those of the Brassua but not of the Hermon; for the.A. horizons they are very much lower than either. The process causing the eluviation of collOIdal sesquioxides from the upper layers and their subsequent deposition in the lower B layers has been about as effective as in the Brassua, Hermon, and Beckett (4,. Likewise, the silica-iron oxide and silica-alumina ratios indicate the effectiveness of. fractionation, although transfer of alumina to the B horizon, as shown by the iron oxide-alumina ratios, is not e:-.."iireme. The generally lower silica-base ratios testify to the less severe leaching of the Gloucester colloids as compared with the Podzols. This is in agreement ,,,jth the generally higher silica-water ratios and the ratios of water to sesquioxides at corresponding levels in the profiles. Because of these relations it might be expected that the combined water and the combined water of the soil acid would be greater in the Podzol than in the Gloucester colloids. Such is seldom the case for combined water but nearly always so for the combined water of the soil fidd. It must be noted that the latter is corrected for organic matter and carbonate content, if any, and is, therefore, more significant. In both cases the probable error in determining the organic matter (1) must be considered. The data for the Gloucester soils (tables 8 to 12) taken as a whole seem to warrant the following statement: While these soils are classi fied as Gray-Brown Podzolic soils, the classification is based primarily on their morphological character. The colloids are more character istic of true Podzols. It mlty well be that the porous character of the parent material has permitted the entire removal of t·he more readily dispersed colloidal material, and therefore the residual material is more highly fractionated than is usual with Podzolic soils. Despite their well-developed profiles these soils appear to be essentially .. inlIDature. CHESTER LOAM The Chester soils are of interest here because of their wide distribu- " tion, their agricultural importance, and their close association with the Gloucester soils near the border of the Jerseyan drift. The Chester soils have develop.::d. from mn,terial derived from ancient crystalline rocks of the Piedmont Plateau. They are typical mature Gray-Brown Podzolic soils. They occur as far north as New Jersey and as far south as North Carolina; but in Maryland and Vir ginia the soil-developing processes have prod uced a characteristically well-developed Chester profile. Evidence presented by Holmes and Edgington (22) indicates that the Chester soil colloids have about the same composition wherever found. However, typical parent material, designated the C horizon, is usually found at considerable depth, which may account for many peculiarities of the profiles examined by them. The mechanical nnalysis of a Chester loam from near Rockville, Md., is shown in table 13. Considerable colloid has been eluviated from the .A. to the B horizon. Tins transfer is evident despite the presence of the organic matter in the At layer. The almost complete absence of organic matter from the B t horizon is to be noted. The C horizon is snndier thnn layers above, but it contuins sufficient silt, clay, and colloid to prevent excessive underdruinage, PROPERTIES OF NEW ENGLAND AND PIEDMONT SOILS 25 TABLE 13_-Mechanical analyses of Chester loam 1 Fine Very Fine IOoarse Medium sand, fine Silt, Olay, o 11 'd lorganic o 01 ',matter Sample No. Horl- Depth gravel, sand, sand, sand, 0.05- 0.005-() zon 2-1 1-().5 0.5-().2.1 0.25- 0.1- 0.005 0.002-() by mm mm mm 0.1 0.05 mm mm mm H,O, mm mm ------Per- Per- Per- Per- Per- Inch.. cent Percent Percer,t cent cent cent cent Percent Percen 0167IA______AI (}-2 0.4 ].7 2.7 10.3 11. 7 25.5 15.8 5. J 01671______4 01672______As 2-10 1.5 2.7 11.2 10.0 41. 411 31. 6 19.7 1.1 BI 1(}-34 .5 1.7 2.8 ]2.8 12.1 33.1 36.6 24.5 04 01673_ _ ~ ~ ... __ w ~_ C 34-60 ]_ 4 3.8 5.0 20.4 ]7.4 29.0 22.8 17. ] .01 I_o\.nulyses made by '1'_ M. Shaw and E. F. Miles. The layer of this soil designated as the C horizon is neither a typical B or C layer_ It is a transitional horizon, but is less like the B than the C. The typical C horizon is aften found at much greater depth. The chemical analyses of the soil are given in table 14. The analysis of a gneissoid granite from Rock Creek Park, Washington, D. C., reported by Merrill (28), a,nd presumably the same as the rock from which the soil is derived, is also given in table 14. In this rock, potash feldspars are dominant. Considerable variation in the soil profile is indicated. Silica is about 10 percent more abundant in the A2 horizon than in the B t ; iron oxide is about twice as abundant in the Band C horizons as in the A. Alumina has also slightly increased jn the B horizon. The soil has eX"Perienced extreme losses of mU'b"llesium, cal cium, andsodium, as compared with the quantities of these constituents in the parent rock. On the other hand, potassium has been little affected. This is to have been expected, for potash feldspars are not hydrolyzed as readily as the soda-lime feldspars, nor is potassium as readily liberatedfrom the micas of primary granite or a gneiss formed from It. TABLE l4.-Chemical analyses of Chester loam I Sample Hori No. zon Depth SiO, MgO Ouo K,O NaliO TiO, MnO ----1------.----- InchC8 Percent Percent Percent Percent Percent Percent Percent Percent Percent CI671A____ AI (}-2 69.00 4.42 11.03 0.49 0.25 1.92 n.28 1.29 0.21 CI671_____ A, 2-10 74.3:1 4.52 12.42 .54 .07 1.99 .23 1.31 .23 CI672_____ BI 1(}-34 66. 7(i i. 54 ]6. 43 . 08 . 01 2. 22 . 19 1. 25 .OU 01673_ ____ 0 34-60 M~ Ln J~~ .~ .01 ~~ .~ 1.28 .10 Rock '"______6U.33 3.99 14. aa 2.44 3.21 2.67 2.70 Sample Hori Igni Organic No. zon Depth P,O, so, tion 'I'otal mnt- 00, ., loss ter 3 4 ----1------Inclies Percent Percent Percent Percent Percent Percent Percent P. p. 'In 0]071A___ • AI (}-2 0.10 O. OJ 10.54 100.20 7.80 0 0.20 125 5.5 01671 ____ • A, 2-10 .09 .01 4.44 100.]8 1.54 0 .05 95 4.8 01672___ •• BI ](}-34 .12 Tmce 4.90 100.19 .40 0 .02 60 4.8 01673_____Rock '_. ______a 34-60 _ .10 'fruce 4.115 100.24 .20 0 .Ot 55 4. 9 .10 _.______1 98.77 "------.------ I Analyses made by Olen Edgington. • Determined by W. M_ Noble. 2 Merrill (f8, p. 186). • CO, of the carbonat.es. , Oombustion method (CO,X0.471). G Determined hy E. 11. Bailey. 3345:l°-:{8---4 26 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE The remaining constituents of the soil are not much altered by soil forming agencies except those intimately associated with plant resi dues. This is apparent in spite of the high acidity a"2d low soluble salt content of the Chester, which testify to the thorough leaching of the profile. The chemical analyses of the colloids (table 15) show some interest ing profile relations. As is mual in a podzolic profile the percentage of iron o::\.-ide increases with depth. It is remarkable that the increase is so uniform and has been carried so fa.r. Alumina, however, is most abundant in the A 2 layer. Magnesium and potassium have not been so effectively removed from the colloid as the more vulnerable calcium and sodium. In the upper layers they have been replaced partially by organic residues and the accumulated manganese, phosphorus, and sulphur. TABLE l5.-Chemical analyses of Chester loa.m colloid I Colloid I I i SampleKo. BOri·1zon ., Depth extract· RiO, J'e,O, , AIoO, )lgO C"O X,O :\'a,O TiO, ed i i___ ------Inches Percent Percent Percent iPercent Iperce: I-'CTCC1lt P"cent Percent Percent 01671A.",1 A, I 0-2 (iO 37.30 11.li4 27.17, 1.06 0.37 1. 70 0.15 O. i1 G1671.''l A, 2-10 40 38.63 13. ~O 29.5·1 1. 08 .11 1. 71 .16 .7o C1672 ",,' TIl 10-34 59 39. 00 17. 56 27.40 1. 11 .04 1. 58 .13 .84 C1673 1' ""1 C' I 34-60 07 30.52 20.21 2;.59 .97 0 1.44 .11 .89 I ]Jori, I Ignition Or~anic Sample No. Depth MnO P,O, SO, rrotul rnatter CO," N' zan loss " ------i Inches Percent Percent P'reent Percent Percent Percent Pt7Cent Pacont elfi7lA,_ "_""_~- AI 0-2 0.19 0.53 0.11 lR.97 99.90 8.72 0 0.19 01671, _"""'__ "\, 2-10 .12 .26 .10 13.86 \*1.57 3.84 0 .5 '_'1 TI, 10-34 .07 .15 .02 1I.S7 mI. 77 0 .1 01672'._","""" .04 I e16i3 I" .,"""" C 34-00 .00 .20 I .02 11.\!o \19.91 .81 0 .1 I I Dispersed with ammouia. , Determined by the combustion method (CO,XO.4.11. 3 Determined by W. M. Noble . • CO, of the carhonates. If these analyses nre corrected for the ignition loss, silica, as expected, is most a.bundant in the surface horizon, and quitp surprisingly the amount decreases with depth in a fairly uniform manner. The percentages are 40.1,45.1,44.3, ancl41.5. Undoubtedly the C layer has profited to some e.x"tent by the eluviation of colloid from layer" above, and probably contains more of the more mobile iron oxide, combined or free, than is usual in a typical Chester profile (22). The characteristics, as 'well as a few of thepeculia,rities, of this profile' are still more boldly illustrated by the derived data combined in table 16. The silica-sesquioxide and silica-iron o::\.-ide mtios of this profile arc confusing if due account is'not taken of the unusual abun dance of iron o::\.-icle in the lower horizons, particularly the C layer. It was expected that iron oxide would concentrate in the B layer with the eluviated colloid. As previously noted, in this soil the iron o::\.-ide has been carried even lower than is usual, thereby causing both ratios for the C horizon to be much lower than those for the B. Evidently conditions are not fa,Yomble for the precipitation. of iron oxide in the B layer, but they are in the C. It appears as though fractionation PROPERTIES Ol!' NEW ENGLAND AND PIEDMONT SOILS 27 of the colloid in the upper layers has followed a little different course from that in the lower layers. This is expected in 'l.n average profile as defined by the soil series. . TABLE 16.-Derived data: Chester loa.m colloid ]i'orrnula ratio SumploNo. Horizon Depth SiO, SiO, SiO, Fe,O, j SiO, Fe,O,+AbO, Fe,O, AbO, XT;(7; Total bases ' Inches 01671.'1...••••...... •.. A, 0-2 1.82 8.41 2. a3 0.278 11.63 0167L...... •...... A, 2-10 1.72 7.72 2.22 .288 13.00 01672...... ••.•..•••• TI, lo-a4 1.74. 5.85 2.42 .414 13.62 01673••••••••••••••••.•• C 34-60 1.53 4.80 2.25 .469 13.92 Profile avemge •.....•.. ------1. 70 0.70 2.30 .362 13.04 Forlllula rIltio Oom· Com· bined SUlIlpleNo. Horizon Depth bined water of SiO, B,o 2 B,o , H20' water 3 the soil H,O' 1<'0,0,+.'1.120, Fe,O, .'1.1,0, acid' ------11----1------ lnc/ws Percent Percent 01671.'1. .•••__ A, 0-2 0.996 1. 83 S.44 2.34 10.25 12.31 01671...._•••• ::::::: A, 2-10 1. 061 1. 62 7.28 2.09 10.02 11.36 01672•••••••• ••••_••. B, 10-:14 .W3 1. 75 7.78 2.44 10.93 11.90 01673.••.••.•• __ . __ (' --:lHiO .922 1. 66 5.20 2.44 11.10 12.00 Profile nveragc____ -- .99a Lit 7.17 2. :13 10.57 11.89 1 Oxidps of magnesium, calcitnu, potassium, and sodium. 'Water of combination plus water l'quivalent of the bases. 3 Ignition loss less the organic matter. • Water of combination plus water eC]uiVlllent of the bllses, correctet! for organic matter and carbonate content. In the light of data assembled by Holmes and Edgington (22) a concentration of either iron oxide or alumina in the 0 layer might be expected. Of the six complete profiles presented by them, all have a greater percentage of alumina in the 0 than in the B layer; two have a greater amount of iron oxide in the 0 than in the B horizon; and in half of them the silica is less abundant in the colloid of the parent material than in the zone of accumulation, the B layer. Such a dis tribution of silica and sesquim..-ide in this profile necessarily affects the silica-sesqui()xide ratio of the various soil horizons, and the net result is that in two-thirds of the profiles the silica-sesquioxide ratio of the o horizon is not so great as that of the B. These results assure us that it is not unusual for the alumina or the iron D).ide or both to be more abundant in the 0 horizon than in the B, both with respect to themselves and to silica. The silica-alumina ratio (table 16) is fairly constant throughout the profile. It therefore naturally follows from the previous paragraph that the iron mdde-alumina ratios are greater in the Band 0 layers than in the A. Alumina, therefore, has not had the same freedom with respect to silica as has iron oxide. A few data remain to be noted. The silica-water ratios and the water-alumina ratios individually do not depart far from the average of the profile. But the water-sesquioxide and the water-iron mdde ratios are not so constant. This lack of constancy in the profile is 28 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE not altogether due to inaccuracies in computing the combined water of the colloid. The combined water and the combined water of the soil acid are remarkably constant throughout the profile, irrespective of possible errors in their computation. MANOR LOAM As noted by Marbut (25) the Manor soils are closely associated with the Chester. They are, therefore, of considerable interest. As men tioned in a previous section, the parent material of both series is the samei but on account of topographic position, erosion has destroyed the symmetry of the normal regional profile. The Manor soils occur on slopes in fairly well dissected areas; the Chester, on the other hand, are found on gentle slopes or on nearly levelland. The mechanical analyses of a Manor loam from near Tysons Cross Roads, Va., are presented in table 17. These data are comparable with those of the Chester just described. Nothing unusual in tex tural relations is apparent. The greatest amount of clay and colloid occurs in the B1layer, and the sand and silt are more abundant above and below this layer. Partial or complete removal of the A layers by erosion has doubtless repeatedly ocourred during the development of the Manor soils. Presumably the damage has been partially repaired since those events by the re-creation of the surface layers of the soil from the former subsoil. Eluviation, however, has not carried the colloid deeper than the B1 horizon; it is, therefore, the heaviest layer in the profile. The presumed events are substantiated by the heavy A layers. The textural relations of the soil nevertheless are those typical of the Chester, the normal soil of the Chesapeake Bay Pied mont area. Itis therefore apparent that evidence of profile asymmetry must be found elsewhere. TABLE 17.-l't'Iechanical analy8e.~ of lklanor loam 1 Fine Very Fine Ooarse Medium fine Silt, Olay, Ooltoid, Hori- gravel, sand, sand, sand, sand, 0.05- 0.005- Oragnic SampJeNo. zon Depth 2-1 1-G.5 0.5-G.25 0.25- 0.1- 0.005 Omm 0.002-G matter mm mm mm 0.1 0.05 mm mm byH,O mm mm ------Per- Per- Per- Per- Per- Per- Per- Per- Per- 0812______Inches cent cent cent cent cent cent cent cent cent 0813______Al 0-1 2.S 3.0 3.2 11.9 IB.O 26.4 IB.5 12.7 14. 6 OS14______A, 1-8 1.6 2.5 3.1 14.6 21. 9 27.9 27.0 lB. S I. 1 BI 8--17 2.0 3.3 3.2 15.7 23.3 22.2 29.9 23.5 2 OB15______B, t7-40 3.2 6.3 4.7 21.2 29.2 22.2 13.2 B.5 0 OS16______C 41}-56 2.0 4.0 4.3 25.0 30.0 27.5 7.3 4. () 0 I Analyses made by'!'. M. Shaw and E. F. Miles. The chemical analyses of the soil (table 18) present no evidence of a mutilated profile. The B portion of the profile contains less silica but more iron and alumina than the A or C. Although the nearness of the heavy layer to the surface is doubtless due to erosion, the chemical analyses do not disc lose any unusual features. Leaching has been thorough; calcium and sodium have experienced consider able losses, but comparison with a representative analysis of the parent rock shows that with the exception of a few cases more than one-half the various constituents still remain in the soil. The chern· ieal analysis of the soil might pass for that of a typical Chester. PROPERTIES OX' NEW ENGLA.L'iO AND PillOl\IOXT SOIL~ 29 T.ABLE IS.-Chemical analyses J of jllanor loam Sample No. ~g~i. Deptb SiO, F~O, IAhO, IMgO I GIlO ! K,O INluO ITiO, I MnO I ----1------I-- Inch .., C812 •••• _--' _~ I ()-1 P",w' p,re'"'I""'"'!"''''''P''''"' P""~'P"'W'(""""P""" A. 1-8 "-" • d "... I «" • "I ,..• I 0." '" ... M.." , ... ,,~ ••OOi ... ""'! ." •• n ... CBl4.•••___ B, B-17 58.62 9.07 20.66 .81 .051 3.62 .21 1.11 .07 CBI5e'..••••······1__. B, 17-40 59.7.S 8.79. 19.!}3. .1121 .03 I 4.12 .13 I 1. 21 .12 CBI6•.•••__ C ~0-56 71.39 6. O~ I 14.29 .58 I Tr, 2.68 .Oli 1.18 . 12 CBI6B••••• Rock! __ ,.•.._ 55.90 I 11.3. I 19.58 I 1.08: 0 . 5.20 .30! 1.30 .06 Sample Hori· organiJ Depth P,O, SO, Ignhion! Totlll milt. CO," N' Soluble pH' No. zan loss ter,3 salts --I1 lnche. Percent Percent Perceni Percent ~\~ Percent P.p.m. C8IL.•_•• Al ()-I 0.10 0.17 17.49 00. GO 13.52 0 0.35 750 3.8 C81L.•••• AI 1-8 .05 .07 5.30 99.91 1.53 0 .04 185 4.2 C8IL.•••• B, B-17 .Il .08 5.66 100.07 .48 0 .02 255 4.0 C815••.•••• B, 17-40 .07 .07 4.66 00.80 .47 0 0 380 3.9 C816._••••• C 40-56 .00 .03 3 .•,2 00.87 .Oi 0 0 210 3.7 CSI6B••••• Rock 1...__. __ 0 .05 ~.Ml 99.43 0 .Im -~-~--~- I .. ------... ----_#_- I Analyses mllde by Glen Edgington. • CO, or the carbonates. 'By combustion method (CO,XO.4il). 'Determined by E. n. Bailey. 'Determined byW. M. Noble. The chemical analysis of the colloids presented in table 19 indicates certain points of disharmony in the profile. Silica is unusually con stant in quantity when considered on the inorganic basis. The rela tive quantities are 47, 45.3, 46.2, 44.5, and 40.4 percent respectively. Eluviation undoubtedly has occurred (table 17), but no zone of fractionation is sharply indicated. There is apparently a little ac cumulation of alumina in the Az and B layers. The distribution of silica and sesquioxides is not therefore indicative of a characteristic regional profile for the whole podzolic area. TA.BLE I9.-Chemical analyses of l1Ianor loam coUoid Colloid Sample !lori· Depth ex· SiO, Fe,O, AhO, TiO, 1.0n MgO 1 CaO K,O 1 NIl,O No. tracted Inches Percent Percent Percent Percent Percent Percent Percent·Percent Percent C812.o..•••[ A, ()-l 16 3a.63 8.83 24.39 1.12 0.17 L87 O.19 0.55 C813...... A, 1-8 17 37.S9 11••18 30.82 .87 .02 1.87 .28 .55 C81L..... B, 8-17 12 40.28 12.72 30.35 •liZ .17 1. 53 .13 .70 CSI5••.." B, 17-40 4 38.72 14.•,S 30.04 1.03 .00 1.30 .15 .70 40-56 6 19.57 28.55 .7.1 .04 1.17 .IS .75 CS16·······1 C 35.35 I Hod· Organic Sample No. Depth MnO P,O, SO [Ignition! Total nUlt· CO,, N' 1.0D . l loss I tor 1 2 ------Inche8 Percent Pere ~----. I Determined by the combustion lIlethod (CO,XO.4711. 'Determined byT. H. Harris. , CO, or the carbonates deterlllined by W. M. Noble. The distribution of the other constituents in the colloids of the profile is very similar to that in the Ohester described above. Oal cium, sodium, and the carbonates are low and testify to intensive leaching. Potash is higher in the soil than in the colloid, presumably due to the mica content of the soil. 30 TECH])'''lCAL BULLETIN 609, U. S. DEPT. OF AGRICULTURl~ The derived data displayed in table 20, however, effectively dis courage any attempts to discover in the colloid evidences of frac tionation in the course of profile development. No systematic frae tionation of the eolloids of'the Manor is indicated by the ratios, and no specific zone of iron aceumulation is shm\'Il. The accumulation of bases in the At horizon is dear, though not so sharply defined as usual. The debasing of the entire profile is indicated by the sillca total base ratios and accords with the pH values shown ill table 18. 'rhe luw pH value for the A 1 horizon despite tbe rela.tively low silieu total base ratio of the eolloid is to be ascribed to the acidity of the orga,ruc matter. The ynInes sho\\-n for the combined water' of the soil acid are nearly identical \\-jth those of the Chester profile. TAllLl') '20.-Derived daLn: llfallor [OUI//. ('ollo-id 1l(·JllI. l·~·---~·· Inches ' I CSI2•• ___ ._. __ .... II-! ' L\Xl. 111.12' oj 31 j' iI.Zl1; 10.:l~ CSI3.... 18 I 1. OS , ~.1iIi 2:i1S, .2~nl 1:1. Ii! CS1L.. ___ .. "':liil 1.7SI ~.41 2.2fij .2tm 15.42 rsI5.... 17-'10 1. 67 I •. ()6 2. III . :llll . I:!.:if, ('BIG .• 4(Hil\ 1.45! 4.•:\, 2.10 .44-11 17.00 ------~-~·I-~~-,------Prom!' n\'"rng" L .U •. ~(J 2. 10 I .W!) : 13.115 --======, Form\lla rutl0 Com", I hiDt'd RnmJlI~ ~(j. Horizon D('ptll, I 'I Wllter of _ll Q2...... ~(~Z ..lJ,Q.'--"I WIl«'r"~~l:~:i the soil , F("O'+ AhO'j I''<'~(); , A" 0, . add' ! ,~--. 1---'---- _ '-'_~_ ! I Jllrlll.~ , I PeTCt'ul. Percent ('812_ A, . "1 1.lml 1.1'1 I~. f~2 !?!!:t I h.GJ ('Ria I 12.(J2 A, . IX .V:W 1.7!1 U.25 i 2.:!2 I 11. ~V I i H, I h (. i 12.05 ('814 ... l.Om 1.1l8 I 2. I:! i tn. 50 l 11.6:3 C8J5 _ 11, . I'-W .!I(iO I 1 -I) ~.~~ i I . ,- :!.2G 1 11.22 r 12. Ii> C8IfJ. (' ·1(Hifl I .~lIg 1.1\1 ft ~;)(\ t 2.:14 1l.1Il I------...... [ l1.V4 Profilt' nvern~l'_~ ___ ~ . !IS:) 1 72 i.fii 2.25 . 10.67. 12.()8 -- ---..------ 1 Oxidt.'s or Inugnl'siuUl, ('tlll~iUlIlr pot.ussium, nnd sodiulll. 2 ""'nttlr or ('otuhinuticlJI plus WIlll'r Njtzi\,nit'nt of tilt, hmws-. 3 TJ;IJitiun Joss less Lh(' or~llnic Illllt.I,·r. • \Vater or comlJioation pins wut(lr p It mny be nottld, however, thn.t the averages of the derived datu. of the Chester and the 1111.no1' arc nearly the same, item for item. Other points of similarity also oceuI". Th(~ C layers are apparently .nllke and could be exchanged wit/hout illcoDvenienee. The silica-sesqui mdde ratio of the C laver is lower than that of the lavers above; no doubt, due to tile abtindu.nee of iron in tbis horizon. ~ The ratios of water to sesquioxides 11nd aluminlL, like those of the Chester, .are nearly constant throughout. It seems npPILrent that the hydrolysis of the alumino-silicates of the colloid is the same to the full depth of the profile hut, as noted in the pamgraph nbo\rc, tIle distribution of a part of the resultant produet,s is rIOt uniform throughout the soil. Wbile erosion has interfered somewhat with the development of a normal PROPERTIES OT NBW ENGLAND AND PIEDlVIONT SOILS 31 profile, yet the same general environment has produc:ed from similar materials a colloid essentially similar to the colloid of the Chester serIes. CECIL SANDY CLAY LOAM The Cecil soils belong to the Red and Yellow group of soils as defined by Marbut (25). They are of interest since they are derived from granitic rod,-s, they are importnllt soils of the southern Piedmont, and they !Jossess the chnructeristic In.teritie- properties of a highly weuthered and leaehed soil. The Cee-il siLlldy day loam from near Statesville, N. C., wus selected as a. represelltatlYe of this group. The duta for the first tlll'ee horizons were taken from United States Department of ~\grie-ultUl'e Teelmie-al Bulletin 316, the data for the C horizon were taken from Tedmienl Bulletin 484, and other da.tu have been added. The layer desiglluted ~lS C wns sampled some time after the fh'st tIu'ee were obtained but presumably from the same location. This is a tnmsitioll In.yel' between the typicnl B and the typical C. The typical C horizon is fOUlld at mue-h greater depth. The mechanical analyses of the soil are presented in tuble 21. There is considerable variation in te:-..-tme in the profile. The A layer is neurly twice as sundy us In.yers below. The B horizons contain less silt than the A or C. The difference between tho A and B horizons, however, is supplied by u twofold increase in the day and a tlueefold increuse in the colloids of the B horizons. Both clay and colloid have been eluviated from the A horizon to the lower horizons. The textUl'al relations, therefore, illdieate normal profile development. 8alllp!(.No. 6U7i12M~_ 61178 " .••. 119711 ' ••. \l·1l8 '.' 1 From t·. ll. nt·pt. A~r. '!'<·ell. HUll. aw (!JII •. , Solution los,; !lot iO(·ludl'd. J .Frolu U. S. Dept. Agr. 'I'l·t'll. Bull. "b·1 (/.1,. The eompletCI1l'ss of profile development n.nd the degree of wen,ther ing of the Cecil soil are shown by the ehemieal ullulyses given in table 22. The huger quantities or siliClL nnd potash, us eOll1pnred with those of the colloid, are due to tho pl'e:'lonee of lIndecomposecl quartz and mica. The iron oxide aneL uiLuuina of the A horizon have been dimlliished by cluvin.tioll, 01' otherwise, to about huH the quantities shown by the B horizons. No analysis of parent roek is givon in tn,ble 22 since the schistose layers of pm'e!lt rock are of extremely variable composition and extend to great depths. Nevertheless it seems certain. tbu.t extensive remoyal of magnesium, Ntieium, sodium, and potash Ims oeclUTed dm-iJlg the weatherin~ proeess. Leaching has been thorough. The pH valuG;; are not so 10\\' as in the Podzol soils, but they a·1'e very low for a soil of tho colloid composition shown in table 23. It is probable that the high pH vulue of the A layer is 32 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRJUULTURE due to the replaceable bases of the soil. The pH value is presumably influenced by the character as well as the quantity of organic matter in the soil. All the data indicate extensive eluviation of the insoluble produ.cts of weathering to the lower parts of the profile. In fact, the sesquioxides probably have penetrated to greater depth than indi cated by the analyses. TARLE 22.-Chcmical analyscs oj Cecil sandy clay loam Sl1mpl~ No. ~g~i- DOIlth SiO, IFe,O, I11.1,0, ! M~O CnO I K,Q Nn,O TIO, MnO Jnrli~'.'f Pr[CI'1,li '-;;;;;;;;;; -;;;;;:;;;1" I'CrCr1!t PeTer;,t Ptrc~'nt Perclnl. Perc~1lt Percent 6977 1 __ _ A O-!'q ~.,.(J~: 4.~1I 11U.~q o.~~, 0.:12 O.~I O.O~ 1.24 0.21 6978'-_ TI, 11-.1. bl 1_ n.1I1 HI.•Jf> •••1 .28 ..,0 .0.1 1.33 .06 6979 1 H: :12-00 57. a2 11.20 22. J(I .28 .26 .4:1 0 ! 1..~1 i .06 9418'.... C IHJ-H·I 5-1.50.11.27 2:1.05 i 'I'mue .07 .:14 .1l1: 1.69 I .10 pH !J.6 4.9 4. {I 4.0 1 FrOID U. S. Dept. A~r. 'J'och.llull. aHi WI). , FrOID U. S. Dopt. A~r. 'J'O<:lI. null. 484 (IS). 3 D~torminod hy combustion mothod (CO,XOA71l. , CO, of the carbouutoH. The analyses of the eolloids of the profile are recorded ill table 23. They show but slight varia.tions ill eomposition ill the viLrious horizons. Such vnriutiollS as appear are not greuter, in geneml, than those shown in different profiles by the uIHLlyses of the Cecil eolloids reported by Holmes and Edgington (22). The minor eomponents of the colloid are slightly hi~heJ' ill the A horizon, and this appears to be due largely to concentratIOn through residual plant ash. The eolloid consists essentiu.l1y of silica., alumina, ferrIC oxide, n.nd volatile material (ignition loss). This fact is indicntive of the thoroughness of the decomposition of the parent roel.:. On the inorganic busis, silica., iron oxide, and alumina constitute 93.4 percent of the colloid. TABLE 23.-Clwmical analy.~c.~ oj Cecil sandy clay loam colloid 1 ------~------Suntplo '. ('ollclid HOT!- lJepth tl.,trncL' SiO, MgO CuO ! K,O NII,O I 'riO, No. '011 cd i ------"};;;;;;; J~(rcelll -;;;;;;;;, ~ Percellt j:.JcTcelli -';;:;:;;;;11~ ~II Perccnt 61177' __ ,\ (HI fill :l2.HI 12.57 :J:UiII O.HI O.UO 11.57 0.24 l.lifl 11078'... II, 1i-:J2 00 33. an 12.20 :J0.4·1 . ua .47 .47 • Ii 1.41l 01l71l'". II, !l2-tiU 70 I :Jr.. 7.~ I 111.17 :12.22 I .:14 .·Ii .:15 .10 1.40 3 9418 I (' fill-S·I I a!). L:l I 17. !i.I: aO.52 j .22 . I) t .04 . OJ 1. 65 ! : : 'I'. 'I Or- I SIIlIIplo No. lJurl Dept.h M nO I 1',0, ; 'rowl )!IlIliu ('0.' N ZOtl I ,,° 3 ,1~l~!l.OIl 1 ~ t. 5 muLtor 4 I 61177 ,______"' -;;;;h;;I-P;;rc{!'uifl~I' Pt'TCe7;~ ~ J:>ercellt Pt:Tctnl ;;;;;;;;;;'--;;;;;;;;; 6117g , ______.. A (Hi II. ·1:1 0.:12 U.Oq IIi. 115 UX1.118 2. ao U.05 0.15 II, u-:l21 .14 .2(1 .U') 14.25 Inl.lll .27 .04 .0. tlII79'. '_" __ '" 112 a2-(l0 .10 .:11 .Il') 12.11-1 100.28 • Oil .U6 .06 11-118', .... _ (' tK)-84 ! 12.~.'i .4fJ 0 .• _..... J DisperHed with IImmCluhl. 'From U. S. Dopt. Agr. 'l'oeh. lIul1. :110 (31). 3 From U. S. Dept. A~'l'. 'l'eeh. Hul!. 48·1 (1m • • Determined by tho combustiou method «,O,XO.4il). ~ CO, of tho cllrbouutos. PROPERTIES OJ!' NEW ENGLAND AND PIEDMONT SOILS 33 The derived data presented in table 24 an' concrete evidence of the relations just mentioned. The silica-sesquioxide and silica-alumina ratios HIe smaller in the A and B1layers thanin the B2 and C. Moder ate variation in these ratios for the Cecil colloids has been shown by Holmes and Edgington (22) and others. Iron oxide, hov,'ever, has migrated to the lower layers as indicated by the somewhat lower values of the silica-iron oxide ratios of the two lower horizons. In fact, the iron oxide-alumina ratio indicates a greater transfer of iron in this direction than of nlumina. Slight fructionation is evident. The silica-base ratios of the fiJ'st two horizons are about the same as those of the colloids of the New Jersey and New England soils, or slightly higher. They aTe about the same as those of the Chester in Maryland and the dosely asso('ilLt~d MaIloI'; but in. the lower layers they are from 2 to more thaH 10 tunes b'Teater than 111 the more northerly soils. Leaching of the Cecil subsoil has been extreme. The basesnot removed by percohLting ,vater, however, appear to have been transported by vegetation from the lower to the upper horizons. TABLE 24.-Derivcrl data: Cecil sandy clay loam colloid 1 Formultl ratio SlImpleNo. I llori7.0n 1 ]Jepth SiO, SiO, l SiO, I FelO, I SiO, ______I __~_I--- i_I"_c'_O_,+_A_b_O_,, _F_c_,o_'_l AI,O, :\1,0, I Total bsses , 1 : Tnc/Ie.. I I 6un ' ...... : A (HI I 1.3:\ 6.!l4[ 1.65 0.2:18 13.36 6978 ...... : HI (;-:12 1. 281 7.26 1.55 .214 1•. 92 6979 6...... __ •• __ . H, I :J2-flO • l,.j:\ 5.8. l.&~ .320 25.01 IHIS ' ...... , (' ! 00-84 1___1_"_1:1_;___5,_:1_1 1.95 .3US 58.80 Prolliellvomge.. "i--:-:-:=:---: l.a'l (1,35 i~--;asl 28. i1 Form,,11I mtio Corn· Sample No. IHorizon i Ill'plll L______.. .--.....---- ~!i~~~ \\~~~~;dof i SiD,' H,O' !I,O J H,03 wllter' the soil _____~____I ._!.__ lI,O 3 .Fe,O,+AI,<.J, l'e,O, ._A_h_O_'______II_Ci_d_'_ I ; 11lcht'.'l Perct1lt Percent .61177 ...._...... , A I (I-I) o.r.1O 2.08 10.84 2. [>8 14.60 15.73 tl07S ...... _ ...... __ [ 1~1 I fi-:\~ .e.sl! 1.86 10.S8 2.26 14.02 14.64 12.80 13.2G 6979· ...· ...... 1 Il, I 32-tlO .8(1~ 1.77 7.26 2.:t~ 9418 1...... i (' 110-84 .8:\(1 1. 72 6.40 2.35 12.30 12.63 .~------PrOfile uVl'rng(1 r--· ...... -~.~-----. iil~ 1.85 ; 8.77 2. :IS 13.45 14.00 i • i I Dispersed with ammonill. I Oxides of 1l1ugnosiuII1, calcium, potussiUIIl, and sodium. 3 'Vllter of comhinlltion plus wllter equimlent 01 the buses. 4 Ignition loss less the organic Illlltter. , Wllter oC combination plus wuter equi\'alent oC the bllSes, corrected Cor orgllnic mutter lind carbonate content. o From U. S. Dept. Agr. Tech. Bull. 310 (30). I From U. S. Dept. Agr. Tech. Dull. 48-1 (18). Hydrolysis of the colloid fLpparently is faiTly eomplete. The con stancy of the water-aluminn. rat-ios in(licates that the combined water is more closely assoeinted with alumillfL thnll other constituents. That aluminn remains fairly faithful to the proportion of eombined water in the colloid is fmtller evidenced by the greater percentage of combined water and of the combined water of the soil acid ill all upper horizons. 34 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE The strong affiliation of water and alumina seems sure; for the other constituents this is not so. The water-sesquioxide ratios necessarily are fairly constant because of the inclusion of alumina in that ratio, but the silica-water and water-iron oxide ratios diverge considerably from the average. The first are lower in the upper layers than below; the second are higher in the upper layers. It is therefore extremely doubtful whether much iron oxide has remained hydrated in the surface soil eA-posed to a mean annual temperature of nearly 58.8° F. APPLING SANDY LOAM The Appling soils vary somewhat according to their topographic location, but the underdrainage is never as good as inits close associate, the Cecil. The Appling sandy loam from Georgia was selected as representative of a typical profile. It is of special interest because it offers a grn.dational comparison with the Ceeil soil just discussed. Itis located farther to the south, but the climatic: conditions !!J'e only a little more extreme than those of the Cecil sandy loam from North Carolina. TABLE 25.-11fcchanical a.nalyscs of Appling sandy loam I Sample No. ------lllChc8 Pel. Prl. Pcl. Prl. Pcl. Pel. Pcl. Pcl. Pet. 0822..___ •.._•.. _ 0823______AI 0-1 13.9 19.0 10.1 12. .'i 5.2 la.s 10.9 7.8 13.8 0824______A, 1-0 13.5 10. U 14.0 KO li.O 14.2 9,5 1.3 0825______D, 0-14 10.8 15.4 11.519.0 12. \l 7. i 18.2 25~3 10.0 .5 D, 14-28 ~ 3.6 :U 0820______H.:J 7.0 I 4.71 0.1 US. 0 tlO.O .1 C 28-00 5.7 I 0.0 I 5.7 S.9 8. I I 15.0 46.8 40.0 0 I AnalySes Illude by '1'. 1\-\. Sbaw nnd E. F. Miles. The mechanical analyses are shown in table 25. The sandy tex ture of the soil is evident. The first three layers are sandier than the two below.. Considerable clay and colloid have been eluvinted to the B2, the heaviest layer in the profile. This layer, as well as the layer below, is sticky and hen,vy, and therefore does not allow the perfect underdrainage so charn.cteristic of Cecil soils. The poor underdrain age is evident in the mottling of the lower part of the profile. The composition of the soil is presented by tbe chemical analyses in table 26. The profile shows wide variations in the different horizons. As the result of eluviation of sesquioxides to the B, particularly the B 2, the proportion of silica in the A horizons is greater than the aver age for the profile. In this respect the profile is normal. The excep tionally low silica content of the B 2 layer is due to the high clay con +ent (table 25). The bases have been thoroughly leached from the soil, no doubt due in part to the uniformly high acidity throughout. Consequently the soluble salts are low, although some are retained by the organic matter. Magnesium and calcium in small amounts per sist, but only traces of sodium remain. Potassium remains with the more resistant micas about in the proportion these micas occur in the parent granite. Phosphorus, sulphur, and nitrogen, in the surface soil, are doubtless associated with the organic matter. The high sul phur content of the C layer is unexplained except by the presence of insoluble sulphates. PROPERTIES OF NEW ENGLAND AND PIEDl\WNT SOILS 35 TABLE 26.-Chemical analyses of Appling sandy loam 1 Sample No. Horizon Depth SID, Fe,O, Al,O, MgO CaD K,O Na,O TiO, IMnO Inch.. Pct. Pct. Pct. Pct. Pct. Pct. Pct. Pct. C822.•______AI_____•.••••_ 0-1 74.43 1.28 4.83 0.05 0.14 0.75 Trace 0.55 0.04 0823..••..__ . A,••__....__ ••• 1-9 87.25 1.73 5.65 .06 .04 .79 Trace Pd. i4 I .03 C8U••••.•__ . D,_.______••• 9-14 81. 02 3.11 ]0.34 .06 .05 1.13 Truce .76 .03 C825._.•••••• D,_•.___ .••.._ 14-28 54.01 8.35 25.47 .19 .09 1.20 Trace .76 .03 C826._.••_••• C __ ••• ___ ...._ 28·60 fil.48 6.52 22.56 .20 .oa 1.25 Trace 1. 22 I .03 C827...... _. Frp.sh grunite__ ,' •.••.• 71.40 2.53 15.16 .44 1.38 5.34 2. n9 .4:1 i .04 I 11 gm·. galliCOr.. S o· I Sample No. ; Horizon Depth P,O, SO, tion Totlll mat. CO,, N' uhle pH' I loss ter , , salts ------1______1______------II Inches Pc/. Pet. Pct. Pet. Pct. Pcl. Pet. P.p.ro. C822....__ ... A,....______• 0-1 0.01l 0.1:1 17.65 90.04 14.30 0 0.20 545 4.1 C823••••____., A,...... __ ••_.. 1-9 .05 .05 3.42 99.81 2.07 0 .04 150 4.3 C824.____ •·•• IDI...... ___ •.••. 11--1.11·04 .06 3.58 .100.18 .~O 0 .02 120 4.3 C825...__ .._. B,____ • ____ ._. H-28 .09 .07 9.80 100.06 ..8 0 .02 05 4.3 C826...____ • C... __ ...... 2H-60 .0:1 .12 O.!I!I 100.13 .15 0 0 ! 65 4.2 C827 __ ... ___ • Fresbgrulllte__ .17 .01 .31 100.20 ••__. __ ,..... __ •. __ • ____..______• r._..... 1 1 Analyses mnde by Glen Edgin~ton (except (827). • CO, of the carbonates. 'Determined by comhustioll method (CQ,Xll.471). 'Determined by E. H. Bailey. , Determined by T. n.lIurris. The chemical analyses of the eolloids, given in table 27, are of con siderable interest. In particular, attention is called to the analysis 0 the colloid of the B2 horizon, extracted with and without the assistance of a dispersion agent. The compositions are remarkably alike. Base exchange has occurred, but the loss of the constituents subject to base exchange is greater than the increase in nitrogen in the colloid. A part of the loss is doubtless due to solution; on the whole, however, it is insignificant. Evidently the greater yield of colloid obtained with the dispersion agent would argue against laboriously extracting a col loid from a lateritic soil inherently low in exchangeable bases without the use of a dispersion agent. TABLE 27.-Chemical analyses of Appling sandy loam colloid . Oolloid Sllmple Hon· Depth extract· SIO, }'e,O, AhO, MgO ello R,O Nu,O 'I'iO, No. zon ed Inch.. Percent PercC1lt Perce"t, Pcrcent Perce,,! Percent Perc",t PtTctlli Pucent C822___._. AI Cl-l 1(1 33.70 8.34 26.89 0.42 0.40 I. :14 0.1i O. 62 C823 ••• ___ . A, 1-9 21 3.1.40 9. 84 :1:1.21 .43 .2:1 1. 46 .07 .65 C824 .... TI, IH4 28 35.72 11.84 :15.03 .38 .10 1.29 .09 60 C825...... D, 14-28 18 35.10 13.28 35.13 .:11 .02 .79 .07 73 C825 ' .... _. D, 14-28 62 35.30 13. :15 35.03 ..21 0 .76 0 .71 C826 1._.... C 28-tIO 70 37.38 12.74 :14.118 .25 0 .78 .35 sa I 19l1i· Organ· __S_U_"_11_'le_N_U_._II 1~::~1. I ;lepth MilO p,O, ~ \::~~ 'rotlll Ite~~l; ~ Inch.. Percent Percwt Percent Percent Percent Percent Percent Percent C822...... A, 0-1 O.OY 0.45 0.23 27.00 100.31 17.52 0 0.89 C82:1••_...... __ A, HI .011 .25 • I I 18.45 100.19 6.21 0 .35 C824...... ___ • __ .• B, 9-14 .05 .18 .07 14.98 IOO.:I:! 1.81 0 .10 0825.._...... _.. B, 14-28 .03 .20 .05 14.49 100.26 .85 0 08 0825 1 •.•••-- ... B, 14·28 .02 .21 . III! 14.35 100.00 .OS 0 .13 C820 , ...... _....' C 28-60 .04 .15 .05 12.98 100.23 .34 0 .11 I Dispersed with auuDonlll. I Determined hy the combu~tloll method (CO,XO.471) • • Determined by T. H . lillrrls. • CO, of the curbonates detormined by 'V. M. Noble. The principal profile variations in the composition of the colloids, as shown in table 27, are cu.used by the transfer of iron oxide and 36 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE alumina to the B2 horizon. Eluviation ·of alumina is not so mark"ld, however. The variation in silica is slight. In fact, very little frac tionation of the colloid constituents has occurred. The bases have behaved as might be expected of a colloid of granitic parentage. Sodium and calcium tend not to remain in the colloid or soiL Perhaps itis because of the abundance of the readily decomposed soda-lime feldspaTs in the pl1Tent gmnite. On the otheT hand potassium still remains with the micas, primary OT secondaTY, in the finest fraction of the Appling soiL lvlagnesium has appaTently done like wise; it is about as plentiful in the colloid as in the paTent rock. The usual greater amount of these bases, as well as most of the remaining elements, in the upper layers is supplied in 11 laTge measure by the vegetation. Some of these, particularly nitrogen, are undoubtedly held by the organic matter. Like most of the soils dis('us5ed, the col loid eluviated from the A layers is filtered out in the B, largely because of the lack of bases in that horizon. The deriyed data in table 28 substantiate in a concrete way the suggested relationships. A modera te decrease of the silica-sesqui'o:\:ide ratio through the profile to the 0 horizon testifies to a moderate fractionation of the colloids. This is further evideneed by a moderate increase in iron and aluminn, as compaTed with silica, -in the lower layers. However, a comparison of the silica-iron oxide, silica-alumina, and the iron oxide-ahmlina rntios demonstrates that iron has enjoyed a greater independent change thnn has alumina. Although the Ap pling is most remote fTom the typical Podzols of the north, podzoliza tion is distinctly evident. It is surprising, howeyer, that the fraction ation of the colloids would he more marked in this soil than in the Chester, 11anor, or Cecil soils. TA1ILE 2fl,.-Deril!/'rl data: Appling sand1l1oam colloid Forrnulll rntio Slllllpl~No. ,11(Jrizon Depth "iO, SiO, AGo; '1'otlll bllses I Illches C822••••••••••••••... Al 0-1 1. iR Ill. is 2.13 0.198 15.80 C823 ••• A, 1-1) 1. 62 9.5i 1.81 .189 19.35 C824....::::::::::::.. DI 9-14 1.42 8.01 1. is .216 22.50 C821, ____ ••••••••_.... D, 14-28 1.40 7.02 I.UO .241 33.3S C82.1' __ ...... n, 14-28 1.a7 7.02 .1.71 .244 44.20 C820' ,.~~ .. ~~ ...... ~.~~ .. -. (' 28-1)0 1.48 7. SO 1.8:1 .235 30.95 Profile nverngr .. 1. ·19 8.:17 1.82 .220 ; 27.70 Formuln mtio Com· rOlll. bined SllmpleNo. Ilorizon Depth RiO, bined water or 11,0' I U,O' 11,0' wnter 3 tbr soil 1I,o-' Fe,O,+AbO,· Fe,O, AGO; ndd' ------I7Iches Perce7lt Percent C822...... _...... AI 0-1 O.OH 1.S9 11.45 2.26 10.08 13.00 C823...... A~ 1-9 .830 1. B:I 11.54 2.18 12.24 13.63 ·CB24 ...... HI 0-14 .78:1 1.81 10.24 2.21 13.17 1:1.91 ·CB2.,)...... D, H-28 •iDa 1.8U O. :12 2.25 13. (14 14.0U C825 , ...... n, H-28 .759 L 78 0.25 2.26 13.67 14.00 CB26 ...... __ •.••• __ . (' 28-UO .snl 1.72 0.06 2.13 12. U4 13.07 Profilc Il\"crngc ... "'1==1-- .821 1.81 10.14 2.21 .12.57 ---13.62 1 Oxide..i.i of mllJ:tnesiuIIl. calcium, putnssiunl, nnd sodium. '''-ator of combinnLion Jllus wlIter equlVlllont of the boses. 3 Ignition loss less the orgnnic mntter. • Water of combination nlus wllter CllulYlllent of tbe bnses, corrot'leil for orgnnlt· mlltLer nnd carbonn!e .content . • Dispersed witb ammonln. PROPERTIES OF NEW ENGLA1I.TJl AND PIEDMONT SOILS 37 As in the Cecil, it is evident that hydrolysis of the colloid is fairly complet~. This is indicated by the high sUica-base ratios. The silica water and the silica-sesquioxide ratios indicate that some water is lost by the colloid complex of the Appling after extreme hydrolysis of the parent minerals. The mean annual temperature is 62.2° F. The combined water and the combined water of the soil acid of the colloids in the A layers are lower than in the Cecil, but in the Band C layers they are higher than those in the Cecil. The silica-alumina ratio is fairly constant, but it decreases slightly \'lith depth. Taken together, however, the ratios suggest poor drainage in the Appling profile. HYGROSCOPIC RELATIONS In previous papers the writers (2, 9, 10, 11) have presented con siderable data concerning the hygroscopic relations at various humidi ties of a large number of colloids extracted from soils representing a number of the grea.t groups of solls defined by Marbut (25). Most of these data were obtained in complete profile studies of the physical and chemical propertirs of both the soils and their colloids. Middleton, Sla·ter, and Byers (31) point out the influence of colloid composition on the hygroscopicity and other properties. It has been repeatedly emphasized in these papers that the hygroscopic relations of the colloids are not independent of the chemical composition. The dependence, however, is not close, nor is it to be expected, for many factors besides composition influence the physical behavior of the col1oids. A definite ratio of hygroscopic values at high humidities seems to be characteristic of the great soil group to which the soil belongs. Ithas been noted by Brown and Byers (11) that the parent material has often had considerable influence on the absorptive capacities of the colloids. For the most part, however, the col1oids of the Pedocals absorb the reql1ired amount of moisture at 99- and 75-percent humidi ties to give It quotient of about 2.00. But like studies (9) of the soil colloids which haTe experienced great.er alteration in more humid areas indicate that this ratio may be muny times greater. The hygro scopic relations of t.he colloids of the soils derived from granitic material in New Englund and the Piedmont are, therefore, of considerable interest. As in a pr('\-,jous study (11) the colloids were air-dried, and the various amounts of water absorbed over 3.3-percent sulphuric acid (99-percent humidity)) SO-percent sulphuric acid (75-percent humid ity), and 42.5-percent sulphuric acid (50-percent humidity) at 35° C. were determined. The ra.tios of the peJ'centllge of water absorbed at these humidities b:'y each colloid were cri.lculated. Any special treatment which might alter the properties of the col loids was avoided, if possible. Anderson (8) has shown the change in properties of the ('oJJoids if other cntions are substituted. During extrnction, however, it was necessary, as noted, to disperse a few of the more refractory colloids with ammonia. The data are given in table 29. TABLE 29.-H'aler-vapor absorpUon, absorpl!'on ralios, and base con lent of colloids ~ 00 J3RASSUA SANDY LOAM (Ng\\' l1AMl'SJJlRI ) ------;-----;------;----- wnt~;\~~;r-:;:~~~=;~-----j------A-b-s-or-p-t-io-n-r-n-u-n------;----- ~o Sample No. Horizon Depth ~ 3.3pet. n,so, 13.3pct. H,SO, I aopet. n,so, ICb~~~~\e ~ illche& Percent Percent I'er(eTlt Gram3 C 1438..••••••••• _•••••••.•.••. .\, o·a 21. 80 10.40 S.61 2.10 2.5:J l. 21 0.47l t:t C 1439... _••••. _.__•• _•••••... Il, :H 34. i5 21.8-1 19.35 1.59 1.80 1.13 .144 CI4-IO.. _•••••• _...... __ .•. JI, ~-9 41.90 20.92 23.91 1.56 I. 7.1 1.12 .098 CI4-I1.._•••••••••••••• """" II, 11-19 45. i5 26.49 2.1. iO I.n 1.9:1 1. 12 .288 ~ CI442························· C' 1-----119+ 20.10 13.90 12.58 1. 88 2.07 1.11 .983 ~ 1 ~ Profile u\·erage••.•••.. " .•••• 3-1.01i 19.91 Ii. 64 I 1. i7 2.02 1.11 .397 ~ 0> HEHMON SANDY ],()AM (NE\\- JJXl\IPSHIRg) o C1431...... A, (}-I 20.i8 11.9i 9.20 1.7.,' 2.20 1.30 0.425 CI432.. _..••. _•..... _...... A, 1-5 21.02 11.68 9.95 I.BS 2.20 1.17 .375 ~ 01433.. _•• _••.•.•••• _...... HI li-15 33.60 27.47 24.90 1.22 1.35 1.10 .204 01434...... ____ H, 15-2·1 41. 42 32.35 29.67 1. 28 1. 40 1. 09 .107 rn 01435...... 00. H, 24-32 38.17 30.10 27.6·1 1.27 1. 38 1. 09 .328 C!435A•••• oo ...... __ C 32+ 29.07 21. 04 19.94 1. 31 1.46 1.09. oot ~ Profile a\,ernge._. _..... ___.. 30.83 22.53 20.22 l.45· 1. 67 1. J4 .340 ~ OLOUC'ES'I'gR SANDY LOAM (MASSAC'IH'SE'I"rS) o >'1j C585...... Al (}-2 22.47 11.07 8.03 2.03 2.80 l.a8 0.53·\ > 0586._ ...... __ ...... __ •__ •. A, 2-3 23.20 12.48 10.31 1.86 2.25 1. 21 .506 C587...... H, 3-15 28. OS 10.47 7.92 2. tIS a.51 1.32 .440 § C588...... ' H, 15-30 26.71 10.18 13.47 1. 65 1. 98 1. 20 .588 0589 .. _...... _.. 00' ._._ ... C 3(}-40 18.82 11.79 10.33 1. 00 1. 82 J.l4 1. 349 o Profile average...... 23.80 12.40 10.01 1.96 2.48 1,25 •OSO e (lLOl'CES'l'ER SANDY LOAM (NEW JERSEY' ~ C09I._._ _ 53 13 68 85 8 0.389 ...... AI 0·3 20. 1 2.37 C092...... A, 3-9 I 25.07 11.9.12 1 8.0.75 1 2.751. 1 3.71 I 1.21.35 1 .430 C093...... B, 9-20 35.31 0.32 6.21 3.79 5.69 1. 50 .3OS .~". co94••.•.••.•...•_....•_••..•• II, 26-30 35. i2 8.93 a.O? 4.00 5.88 1.47 .294 C995••••••...•••••••.••••• _•.• B. 36-50 23.10 0.79 5.10 3.41 4.5.1 1.33 .669 C996' •• _..••••..•.•.•••.....•. B. 56-00 26.2a 6.89 5.30 3.81 4. \15 1. 06 .673 Profile average ...... ''"_'_ 27.67 8.70 0.35 3.27 4.52 1.4a .400 CllES'l'ER LOAM (MARYLAND) o~ ~ CI07L\...... ,', .. . A, 6-2 18. 21 ;. it 5. 22 2. 30 3.49 1. 48 0.534 ClIi;L •••_.•.. _.•.. _., .... . A, 2-10 23.17 8.15 5.30 2. g·1 4,37 1. M .495 01072' .•••• _....•. , __...... D, 16-34 31. 75 9.96 5.97 3.19 5.:12 1. 07 .471 § C1673 •• _. ______•..•• "."" C a·l-fIO 29.95 12.25 5.02 2. H 5.33 2. 18 .437 t:J Vl Profile 8yerage._ ... _...... ' ...... _.' ,'_ 25.77 9.52 5.53 2.71 4.63 1.72 .484 o hi MANOR LOAM (VIRUINIA) ~ C812._....• , ...... ,. 1 A, )' (H 17.3.1 7.62 5.69 2.28 3.15 1.34 0.539 ~ C813•• _.•• ,...... I AI 1-8 19.32 6.59 4.64 2.~a 4.10 1.42 .463 C8H...... ,... , I £, 8-17 18.85 7.05 4.48 2.07 4.21 1.57 .441 t:J 0815•. _...... ''" BI I 17-40 10.75 6.02 3.90 2.79 4.30 1.5.1 .418 ~ C816••.•• __.••.. , __..• ", l C' ,46-56 Ii. 54 4.92 3.19 3.57 5.50 1.5-1 .346 Profilen"erage······ .. ···_ .... 1 1__' ...... -. 17.96/ 0.44 4.38 2.85 4.2U 1.48 .442 ~ ~ CECIL SANDY LOAM (NOHTH CAHOLlNA) tj 6977'...... _ A 0-01 28.90 4.38 2.85 6.00 10.15 1.54 0.400 0978 ' ...... D, I 6-32 33.77 4.42 2.66 7.66 12.70 1. 66 .310 ~ r,979 ' .... _...... Dl 32-60 35.49 4.24 2.48 8.37 14.30 1.71.238 9418'.... ___...... _.•.. (' 60-84 30.80 4.46 2.84 6.91 10.85 1. 57 . 193 I-d -----;;::~I---"""7":::::_I·---_::'_:::'-1 Profile a"erage ...... -- 32.2·1 4.38 2.71 7.88 12.00 1. 02 .287 tj~ APPLING SANDY LOAM (GEORGIA) 8 ~ l-3 A, 0-1 17.60 6.04 4.56 2.84 3.77 1. 33 0.355 1-9 20.65 4.73 3.41 4.37 6.06 1.39 .305 Vl gi~=====:::~.~=::::::::::::::i Al D, 9-14 24.05 4.01 2.67 5.94 9.01 1.fi() .2M o DI 14-28 27.32 4.32 2.86 6.32 9.56 I. 51 .175 8 ill 14-28 30.29 4.09 2.67 7.40 11.35 I. 53 .133 Vl 8!~:======:::=::=::::::: C 28-60 34.39 4.39 2.75 7.83 12.50 I. 00 .201 Protlle average .. __...... C.. 25.72 4.00 3.15 5.78 8.71 1. 48 .238 ~ , Sum o[ the [ormula weights o[ magnesium, calcium. potassium, and sodium oxides per kilogram of colloid. 2 Dispersed with ammonia. ~ 40 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE A comparison of the data of the B2 horizon of the Appling indicates that the hygroscopic properties of the colloids extracted with ammonia have been affected by its use. Ammonia increases the absorptive capacity 11 percent at 99-percent humidity, but in 75- and 50-percent saturated atmospheres the affinity for moisture is decreased about 5 and 7 percent. The absorption ratios are changed still more. The differences are doubtless caused by the exchange of ammonia for other bases in the colloid, which certainly occurs, although other alterations not indicated by the analyses may be partly responsible. Since the hygroscopic properties of other colloids in this group are without doubt likewise changed by a dispersion agent, they should be compared with caution if the pretreatment is not the same. The hygroscopicities of the colloids of the eight soils show consider able varIation within the profiles, but there is also a certain regularity in their variation. Except in the immature Manor profile, the colloids of the A layers absorb much less water vapor at 99-percent humidity than those of the B and often less than those of the C. The colloids of the A horizons are about one-half as hygroscopic at 75-percent humidity and one-third as hygroscopic at 50-percent humidity as the average colloids of the B horizons. These wide differences are found only in the Podzol profiles. In fact, the variation of colloid hygro scopicity of all but the Podzols is relatively slight at 75- and 50-percent humidity. The ammonia treatment has perhaps somewhat increased the absorptive capacity of the colloids of the lowest layers of the Gloucester, Chester, and Cecil. The Manor profile is immature, and the colloids do not behave like those of the more mature soils. In general, the avidity of colloids for moisture at the two lower humidities decreases from north to south. The Brassua and Hermon may be reversed, since they occur close together. The order of the average hygroscopicity of the profiles of the Hermon, Brassua, Gloucester from Massachusetts, Gloucester from New Jersey, Chester, Manor, Cecil, and Appling at 75-percent l1Umidity is 22, 20, 12, 9, 9, 6, 4, and 5 pert/~nt. At 50-percent humidity the order is 20, 18, 10, 5,6,4,3, and 3 percent. The percentages so arranged clearly indicate the profound influence of temperature on the hygroscopiCIty of the colloids at 50- and at 75-percent humidity. The higher temperature in the South may have dehydrated the colloids irreversibly and thus reduced their avidity for moisture. This would seem to be most effective on the surface colloids. The warmer climate in the South has caused a more thorough destruction of the clay minerals, resulting in a soil acid of a lower order (13), and this may have caused consequent decrease ill the water-vapor absorption at low humidiLy. Or the presence of more free iron oAide in the colloids may have been a cause. Since hygroscopicity of colloids is, in part at least, a function of the surface exposed, the relative surfaces of these colloids may playa role in the relations noted. It seems probable that DO one of the possible causes is alone responsible. The influence of climate on the hygroscopicity of the colloids at 99-percent hUIll1dity is not demonstrated. Dehydration of the col loids of different composition doubtless produces varied avidities for moisture in a nearly saturated atmosphere, but clear proof is wanting. The surface colloids absorb less moisture than those of the B horizons, but the presence of varied amounts of organic matter which apparently bears no definable relation to the hygroscopicity shadows the influence. PROPERTIES OF NEW ENGLAND AND PIEDMONT SOILS 41 of temperature. Variation of the composition of the colloidS within the profile does likewise. However, the hygroscopicities of the colloids of the surface layers of the soils developed on glacial drift are about 20 percent; those from the more ancient parent material are about 18 percent ifnot treated with ammonia. Itis apparent that the climate, parent material, and other soil-forming factors have combined to produce a colloid having a certain avidity for moisture, but its hygro scopicity at 99-percent humidity assures no clearly distinguishable single cause. There is, however, a relationship between the amount of moisture absorbed at any' two humidities which sharply distinguishes one group of colloids from another, that is, the absorption ratios (table 29). Brown and Byers (11) have observed that these l'n,tios, irrespective of all other consideratiuns, are apparently chamcteristic of ceriia.in groups of soils. It is particularly true of the 99- to 7 5-percent humidity ratios which, for 17 profiles of dry-land soils, had a mean value of 2.13. This ratio for lateritic soil colloids may be, and often is, three times as great. They (11) also noted that the ratios of water vapor absorbed at lower humidities were more constant. Likewise in table 29 the ratio of water absorbed at 99- and 75-per cent humidity by the glacial soil colloids, except those of the lower layers of the Gloucester from New Jersey, seldom exceeds 2.00, and in many instances it is less; the average is 1.72. The Gloucester soil from New Jersey, located on the terminal moraine of the Jerse;yan glacier, has doubtless incorpora.ted in it a hU'ge quantity of the ma terial of the older formation similar to the parent material of the Chester and Manor soils. Consequently the absorption ratios of their colloids are e}.lJectecl to be much aJil.;:e. They are in fact. The average ratio of water absorbed at 99- and 75-pel'cent humiclities is for the Gloucester from Ncw Jersey 3.27, the Chester 2.71, and Manor 2.85. The fl,verage of the tlU'(~e is 2.99, nea.rly twice the average of the first group. Still farther south, and for another group of solI colloids, the a.,verage ratio for the Cecil is 7.38; and for the Appling 5.80. The averuge for the two profiles is 6.42, more than t""ice that of the second group of soil colloids find nearly four times that of the first. But the grouping does not closely correspond with that of the great soil groups, nor was it expected to be coincident. It should be noted that as the soils are more thoroughly weathered, as they have been subjected to increased temperatures, as they have been more thoroughly decomposed audleached, the fl,vidity of their colloids for llloistme becomes relatively less at 75- and 50-percent hmnidity and the absorption ratios (table 29) increase. CARBON.NITROGEN RATIOS The clima..to (temperatmc and rainfall) as well fiS the biological actIvity incident to and dmiug soil development profoundly alters the composition of the organic matter. The carhon and nitrogencontent consequently vary widely in many soils. The rll,tio of the two as tt useful factor in determining one if the other is known, however, is doubtfuL The variation of this rn,t,io with climate, with depth in the profile, and 'with the great soil groups hus beellnoted and commented on by Hilgard (19), by Leighty and Shorey (24), by Anderson and Byers (5), and by Smolik (41). Attention in this study is directed to 42 TECHNICAL BULL:E:TIN 609, U. S. D:E:PT. OF AGRICULTURE the variation of the carbon-nitrogen ratio of the Podzols, Grn.y Brown Podzolic, and the Red and Yellow (lateritic) soils and their colloids, as presented in table 30. The ratios obtained from low values of carbon or nitrogen are questioned. If ammonia was used to disperse the colloids it is indicated, but such ratios necessarily are of doubtful value. TABLE 30.-Carbon-nitrogen ratios 1 of the soils and their colloids BRASSUA SANDY LOAM CHES'l'ER LOAM C/N ruLio 0(-' CjN ratio or- Hari· DepLh _____ .. Smnple No. Snrnple No. Hori· Del,lh ZOn ZOn Soil Colloid Hoil Colloid -----1------11------..---- Inches Inches 01437______._.. A, 5-0 48.7 (2) CHiilA...... A, 0-2 2~.n 21l.6 01438. __ .______A, 0-3 18.1 H. Ii ClU7L ...... A, 2-10 li.8 ~.1 01439...__ ...... D, 3--! 38.0 19.:i ('1fjj'2_, ___ w___ HI IU-:H 11.6 3 :1.4 01440__ ...... D, 4-9 45. :{ 19.6 ('IIi,a...... C ;j·1·00 11.4 ~ 3. 2 01441. ....__ .... DJ 9-19 40. (I 13.0 C1442...... C 19+ 25.0 la.7 HEItMON SANDY LOAM MANOR LOAi\[ ------.---11----· 01431. __ ...... A, 0-1 25.8 12. a C812...... AI 0-1 22.4 12..5 CI432...... A, 1-;' 24.4 10.0 ('813...... A, l·d 22.2 11.5 O14:!3...... il, 5-15 :12.:1 12. :1 CRI,!...... H, IH7 13.9 10.S 01434 ...... 11, 15-24 25. fi 20.7 (~815 ...... II, 17-10 (2) 9.5 C1435...... TI, 2·1-32 25.5 11.4. ('811i.... .-.---- (' 40-.11; (2) 10.5 014:15A...... c 32+ (') 10.7 (lLOlTCES'l'EIt SANDY LOAM. (!lIASSA· 011 [Jswl"rs) CECIL SANDY CLAY LOA],! C585...... _ A, 0-2 3'0,6 12.2 0-0 20.7 A 'S.9 C581i. .._...... H, 2-a 2·1.8 10. a ~!~=IOll7S • ...... H, (j·:J2 fi. .') ! 0' I) C587...... ll, :J-tro IS.4 14.2 flUiit ______~. H2 :12-00 4. II :;:8 C588...... D, 15-ao i7.7 11.0 u.JIs...... _...... C UO-04 ('J (') C589____ ...... C 30-40 (2) 9. U 1 ------'---'-----'---..!..---I!.__...__. ___ -'-I__-'-__'--_-'-___ ULOCC'ES'J'ER SANDY j,OAM (NEW .fI':RSEY) APPL[N(I SAKDY LOAM C09L ...... AI 0-:1 21."7 I') I} C9U2...... A, 3-11 15. B la.·! {"822______. AI 0-1 :l1.9 11.4 C093...... _ H, !J·20 ll.O 11. 7 c82a~~_~~ .. ~~. ___ A, 1·0 ao.o 10.3 099·1 ...... 11, 2()-:!O S.7 U.S ('824...... H, 0-1·1 20.3 10.5 C995_ ...... 11, aO-50 (L4 7.5 ('82.1...... 1\, 1-I-2S 22. H U.2 0996.._..... ___ . B, .50-1j0 ·1.0 , 2.0 ('820...... C 2S-liO (2) , 1. 9 , (Organic lllutter X 0.58) + nitrogen. 2 No nitrogen or or~nnic mutler recordcll. 3 Dispersed with amllloniu. 'With thc cxception of tempcmtll1'e the environmental fn.etors of the New England find Piedmont soils do not Vll,l'y widdy. 1'hc pm'ent material is granitc or del'ived from gl'ltnite. The fOJ'Psts ltJ'O eOlljfpJ'ollS or largely so. The meall annual minfall is 40 to 50 inches, and the mean alliUln.l tempemtm'cs mnge from 43° to H2° F. The carbon-nitrogen mtios of the soils and their colloids prcsent some extreme contmsts. In the soil propel' the ltighest values, 40 to 45, are found in the B layers of the Brasslla; in the B In.yt'J's of the Cecil soil the values are 6.5 nnd 4.9. In most of the profiles the cn.rbon nitrogen ratios of the colloids are much less thn.n those of the soils from the same sample. In gelleral, in the soils and colloids of the Podzols PROPERTIES OF :NEW ENGLAND AND PIEDl\IONT SOILS 43 the ratios are greatest in the B layers; they are lcnst in the most thor-' oughly bleached layers. The carbon-nitrogen mtios of the Gmy Bl'own Podzolic and lateritic soils find colloids in gellern.l decrease with depth. The cn,rbon-nitrogelll'u,tios of the colloids of the Gloucester from J\1assachusetts are similar to those of the Hermon profile. The tempern.ture, the soil-forming process (podzolization or In,terization), and the thoroughness of len,ching are doubtless responsible for the variation of the cn,rbon-nitrogt'll rn tioR. The low temperatm'es and high acidity hfl.Ye efl'(\rti\'ely retarded bacterial decn,y of the orgn.llic nudtrl' of the PoclzolR. Cellulose and other hydrocnrbons (pm'tin.lly decompoRrd) hayr remained in the highly arid layers of the Brussua and Hrl'lllon. There also tIlt' bases lLre depleted, nlld the lignin and protein disperse and pass to lower levels or fl.re entirely rcmoved from the pl'ofil('. At highf'l' tempem tures the Gray-Brown Podzolic Gloucester, (,hestel', n,nd J\fn.llor soils have de,'eloped. The buse content of these soils, particuln,rly of their colloids, is grel1ter, n.nd the ncidity is lesR. As n, n'sult the cellulose is less nbundant, lLnd the lignin nnd protein are r('latiwly' gronter thl1n in the Podzols. At still higher temperatures and with nclequn.te moisture, the lateritic Cecil and Appling soils haye suf\'el'ed tL still grl'lLter loss of cellulose,ln.rgelyfrom bu.cteriu.l acti\'ity, and, propOJ'tioun,tl'ly,stillmore nitrogen compounds J'PlJ1ll.in in the profile in spite of tJlPir low base content. Tempern ture undoubtecUy influences till' cn.rbon-nitrogen ratios of the soil and of the colloid. The results of tlwse enyil'OllmPlltal difl'el'ellCPS and the alteration of the organic soil compounds mn.)' be courrl'tely summn,rized as a.n~rtlgrs f' of the cn.rbon-rutrogPlll'n.tios of the t11l'('o gn'n.t soil groups. The aYer nge yalues for the cu,rhon-nitrogrll mtios of the soils of the Podzol, Gmy-Bl'O\\""ll Poclzolic, l).1lC1 RNI f),nel Ydlo\\' (htt('ritic) gl'Ol.lpS nre 3l.7, IO.fi, mlCll 9.0; mld the C'ul'hon-nitrogC'n rn,tios of their ('olLoids n.yemge 14.3, 10.7, find (i.5. Tlwse l).\'eragps n.m not nltogl'thel' qun,ntitative. Thev inC'lude the 1'u.tios from the surface horizons in some instn,nces find not. in others. Ah.;o S0111e of tho colloids 11n,yo bren. tl'eated with a111 moniiL Howevel', th('y do indiC':lte that the difl'el'l'llC'es of dimn.te find , nll j ts ILttC'ndn.llt phellomenn.llT'P Iltl'f,!:l'ly responsible here for the changes in the cnrbon-nitmgen rtl.tio of these great soil groups. r In other groups of soils otlH'l' fndor's probl1bly modify the carbon nitrogen ratios in the ol'gn.lli(' urat U'l'. Tho ct1rbon-nitrogell n1tios ( reported by Brown :111(1 BYNS (11) fot' dry-Ianel soils :1ad those of four II of the greut soil gl'OUpS reportcd by Andel'son and Byers (5) n.PPl1relltly ~ il.re modificd as n l'esult of ell\'i,'onllH'nt. The presellce of enJeimn in the Prnirir, Chernozelll, Gmy-Browu Podzolic, and Desert soils binders OJ' prevents the solution of the lipuns and proteins of the orgllruc matter. For these gl'C!1t groups thl' rainfall is progrcssiyeiy' le-ss, the profiles lLre less thoroughly lettehed, imd Cltl'hon-ni trogell nttios mnge from 12 for the Pmil'ie to about half tbis qun n Lity for the Desert soils. 1'he ratios, however, do de('['eHS(\ with depth, The en.rbon-nitrogeu ratios of the colloids are n.bout 20 PPl'cetlt h'ss than those of the soils. Rainfall, not tempel'l1ture, is the controlling fador in these great groups of soils. Certn.ln chn,nges in the rIH'mienl C'ompositioll () f the soil organic 111n.tter (humus) I1pplirn.ble hel'C IU'(\ summn.rizt'd by "'11ksman (43): (1) The ('cllulosc Illld hemicellulose disnpPPltl' if condi tions 111'e fayorable to rapid decomposition; (2) the nitrogen compounds ILl'e synthesized 44 TECHNICAL BULLETIN 609, r. S. DEPT. OF AGRICULTURE ~ as the carbohydrates are used by the micro-organisms; (3) flS a result of these two phenomena, the ciLrbon-llitrogell ratios deerease. I t is to be noted that in the humid soils t('mperature chiefly controls the rate of decomposition of the soil organic matter; in the ariel soils the rnte is largely controlled by moistme. GENERAL DISCUSSION For some time there has been a gro\\'ing tenclenc~- for many im-esti gators to COll.<;iclPl" the propertirs of the soil colloi.d ns psselltitlll~ characterizing the soil, its gPIlPsis nncl mot'phol()g~'. In 10:30 HoilllE's and Edgingtoll (22) .l'ppoltp TABLE 3L-·Rt~vil'Wof data; colloids 1IIt.\f;:WA SA;-;IlY LOA"l ---,- ~,-~- ."-.,, -~------"---'~-I-- I \\"nt{'r COItl- nlfJ1}r I I ~ I f;jO, :;io, ::iO~ Ftl.;01 "n ![,o , COIll' biut'd IlIb~.orll'Ahson\' C'onl a ! ,':io,~~.,.lho' ,lll,,!~ j' wntC'l' lion f-j 111lril1Hl ) llt'pth -~-'-·-I hlued lioll hin~tl f"';;i)l+~Cl;);![.'(~i13~i:r;:; ,,\!,J)-; 'J'tH'll b:l:-{-,S I; F("O,+AI,O]: 1'[') I) • ,\T,o; 10 11,0' wHtl'r 3 or 1.1 IIt!1!) per. buses t) M , mUo • i SOli l'l'lit Itll' Heid -I Juhlitr ~ t;j --,-1 if' /J.>"hlif Pat', rtf ' Pr H', nf }ltrrtnt Orum.'i a A, Il ;\ !! II!l 21. 1,"1 (I 111 1..;0 12. ')2 1 S~! 5. 1i;1 I S. :~;i ~lJ '1 H 11. ao I. "7tl 21. 2.10 O.47l "'J Hz, 1 u .f;'" 1, al I ,'-It I .h"i: IU, tI.-) : ,:!:H :I, III W:!;; a,1;21 I;', fi51 20, 0:; .\1. Ull l. 51) •ODS C 1~1~ ~l) I 1.1.\ " ;IU . 1 . ~HI I li.2:; , .ifh 2.11j U.1l1l 2. na I I 35 I.; (Ill 20, tU l.XR .Ilsa !;i t (, t .~r; Cllmph· 11r ,m· n"'ra\!t' III ~t.m L ;:\ 12.7U l .I)U:.! 2. :,1) I:; ,u 3.111. II.U2j 1'.71 31.(1) 1.77 .397 M ____ • --L. -'-_~ ------'------~, __ __ -' II I·;1C\l 0:-; f;,\:-:lJY I.'l.\:\l M""" ~ .\z 1 :, .. '- 11 0.-125 I~~",'-,I -;-';I7.:~;I· Q Hz ).- ~l 271· til ,\. lU I 7ti. .1'-1t 2L~:~Hi :;1 .'.!!;/20,.1l '1 'l') I't·\\} ;1, :,.\ 19,:11 211.15lU.ll11 2l.92141.42 l.SR I :13"1 II I -;1 1 " a, \' I l.2H I .107 t" t' :J1-'- ,," .., Is '1,""'11 III " I'll' Ii, Iii :\tlli .,- -I a. til) !?o.s;J 2·" 35 20. OJ L3,1 .li04 ... C'Hn,l "1'1 fl·n!t' ·\\Pf· ... '· : ! ~I 1 I;, .211; ~.~;i~, "11 ;1. I~:l I'I.:!I; ,··,n ao Vi. 25 21'. un 3U.X:! 1.·'5 .3,0 o~ ,iLUITE:;'I'I':R :;AXJJ\" LO.\:\I (~I.\I':;A('III·I'I-:TTI'I ... b>( A~ 17 tl H, "2;j l.i . (111'I· ~1-2"~~ 1'\~23\'-1--1\-''l:' Il~;:1Jl. 7. D. I· 2.10 11. Hili 2.2,,1'1 I ---;-. · "I ;\, ;'11 . ,II .221 ,l.;;Ii. 271 1- 2 aI I lL .J,' :ua 117,71!1.."71' 21.:J~ 2H. OS --;:-;;I'Q.5:i:i2.ti~ .449 t' ;111,jO t J ~r; U H1 2 2~ .1111 4. if) . "'7:i :! 2'i lH.20 2. HI U.22 1:i. IH IS. ~2 I. no 1. 349 f-d CdlUI'ldt·pr f ,lU·"i\"l·r;It'(' Uti '\lI_.~3."..:.:: ___ ~_= __ .::.:_..~~_ :ll:J 1l.h2 17.~123,~1i 1.911 .1l85 t;J o OLOITE:,'!'EIt f;AXIlY LOA;\I (XI'''' JEH~I';Y\ !>',.., a i.O'-: ! o.:~~9 ~ J1:1 :.~),f.31 A, 211 10, 5i' lifo. J21 Ilz ;JU I 3. ,~ • H5 .22\1 It. 20 • :\211 12 2,/)12 W. 51 211.~,~ as. 72 .1.OU .294 H 12:11·nu III II. 41 'I I llt" "~ ~~_.... _ .__ ntl I~t) I 1 Iii S. 22 2.09 .2M U.51 .Sin \Jl 2. :19 11.91) la.31 2ti. ?,\ .Oia '~TI"'" """ u.~sI ula.Sl I I rr. ~4 'il !), nl} 1.12 5.21 1. . 236 554 II.; 2.64 14.67 10.86 2;.07 3.27 .460 ('llll)l)I"\CJ,rl~~~"~~~:~_1:.--... 10.08. a --.---. ~-- ..~ -.~-~-~------. ~ -~ I Oxitit\5 of lllag'nrsiurIl, l'alrlUIH, {llltnssium, and soliilull. t4 1 C-OTllhizwd w:\ll'r IJlus water Plluivai("Ilt of till' bases. U1 t Ignition Joss minus tlteorgllniUIllHUl'r. fi Comhim'u wnlt'r plus wnt(lr l'IIUi\-nlflnt of th{llmsl's, corrrett'd for nrgnuic lI1uLtt\r nnd carhonntc (·!lutenL. I WItter nhsorlwd owr 3.3 \l,'rc~ut1I,SO. di\'itled by the wnt,'r nbsorbed O","'r aD perL'Cnt II,SO •. e Sum of the formula weights of magnesium, calciulll, llotussiulll, Illld sodlulll oxides pl'r kilogrtllll of colloid. J+:>. 1 Dispersed with ammonia. ~ 46 TBCH~lC'lL j,"LLETI:~ G09, u. S. DEPT. OF AGRICULTVUE !;CO'"'t' ..... 'l"r ... I_,n C'!: ...... ,.,_ C':-:r -!''='l~C C'lt.:: u:x <:.:"o;:::::>r. :r.-:r:x:r.: e-i:>?cie-i cl c-.i:'-:ci til~::I";' e-iCt":'Q --';"':~~I ''':'''::-~ ...; :-~ l- :;;. 1_ ~fM=-• gl.:j:;'i .:,:r.:~~.l"i :r'~ct"i ).. """':0: :-J~~ ~~0!':: c:: C'l~:-r;;",,; :':;;~~7 ;;~~~ ;:: ':'~ ...; ':"1 ,.....; ...... ;:;:!~2! ~ --- ~;1:;;S:;: -~!:', y-,. -rt ':.~ ... =o:.:::~l:: ~~2::= ::.. ;:~::!;:! .'":/'--:=':";; -~I-~ ~~;:;i -:-i:"I:'I'Z'1 ~I';'I~I-:-t ~r=t _.r_",:: -1_':'1_ ~ -"I.:~ "::l :J :::.:':" ~.:~: -I -" .r ,. c..; t_ ~':-::"I ;:: r -"1_/ C I ~'" ::§ ,...... -':'1-'. =~.;;; <.. ::: '" ,...;d ':.... .-~--- ~ -':'1":'1-: 1.-= ~ .~.: r -, = ~ ~ --: .:. = :': ..... = ,::;. ~ : ~2-~5=:: E- ~ J. ~ -~ ~ ::::; r -::.:", 1 • .-• ..::-. --::~~-"":: ::: "" r ~;~ ~ ; !3~:;") ~ ~I"I-:.i;. i ::-i ...... ,...;: '"-: r :r-:-I::::I ... , ... = ,.~ .; .-..... ~ SI ... r';.". ~:~~ -~~ ; =~f~ =::.fi e<. ..,i i;- f;. § ;; ,; * ,~ ~ .=:"" -" ;, ';:': I .~ [ .& .,.'""I/: ! '~ ;::; ~ .~ Q UJ'"' ~ ;6 .;.:;::;:..~ ~£L:: I ! ~~.~~ PROPERTIES OJ!' N],W ENGLAND AND PIEDl\I(\NT SOILS 47 The morphology of the soils is indicated in the field by certain observable relations and profile characteristics. A field investigation is not e.Jo..-pected to disclose all the properties of the whole soil, and the distribution of the vfLrious components, such as colloids or organic matter, except as they are indicated by color, texture, n,nd the general condition of the profile. As classified in the field, however, the Brnssua and Hermon are Podzols; both Gloucester soils, the Cheskr, and ~fanor are Gmy-Brown Podzolic soils; n,nd the Cecil and Appling belong to the group of soils defined by Marbut (25) as the Red and Yellow group. The colloid is one of the most importn.nt textural ('omponf'nts of a soil. It oft(,ll is fL eonsidemble portion of the whok, and it is nlwtI,ys present in amounts greater than a ft'w pereent if the material is properly considert'd It soil. If, then, the properties of the colloid alone be considered It proper bnsis for classifica,tion, ulloth('l" arrangement immediately appt'fLrs, 'Without detailing c\·idt'llt differences and similurities in the composition of their colloids untillu,ter, the Bmssua, the H('rmoll, fLlld the two Gloucester soils ma:y he placed for eon n,'niC'nce in one group, the Chester, the ~fanor, the Appling, and the Cecil in another. The difl't'rem'es hetv,-een the two groups nre particulurly noticeable in the degree of debasement of the colloids and the distribution of buses remaining in the various horizons of the profiles. The combined , wt'ight of the fOllr bases (o}.-ides of mugnt'sium, calcium, potassium, und sodium) ])('1' kilogram of colloid is shown ill detail in the last r column. of tn,ble 29 und for the srl('cted layers in the lust ('olumn of tahle 31. In gellernl, in. the first group the colloids of the Bz horizon contain the smallest am01,lllt of hases, and the n.mount in the A horizon is about oJl0-lmlf us grt'u.t as tbnt in the C horizon. In the second group the colloids of the A horizons ('ontnin the most bast'S, and the C layer of nIl but the Appling contn.ins the leust, The deert'ase of base content from tlH' A to the (' horizons is fairly uniform in all this group, but the dp('I·t'tlse is most ll1nrk('d in the In,teritic colloids of the more southern profilt's. The cause is evident. In all the profill's, the base ('ont.ent of the lIppt'r horizoIls is lllaintaillt'd by the vegetlttion nt nbOll t the snnw yn1lle in spite of thorough leuehing' of the whole profile. But in the first. g'I'OUp the pn,I'Pllt mn.terinl is rehLt.iYrly frt'sh, slightly wen.thrrt'd glacilll drift" rich in buses; nnd the pm'Pllt mutprial of the sreond grollp is the thoroughly wen.tht'I'l'cl, thoroughly lenched, and ('ompnru,ti vt'ly :mcjt'llt formu.tions, poor in bast'S, 'nw profile vn.rintion of silicn., iron oxiclp, fmd nluminu, in the colloids of the first group of soils is striking. :Fra.etiolllltion of the colloid n,s it has bpPI1 moved by percola.ting' WILt.PI' to 10wpr }n.yrrs ill the profile is evidenced by the extrt'Illely low sili('.n-sesqu.io~-ide, ::;iliea-iron oxide, and silieu,-alumina rntios of the B horizon us cOlllplu'pd \\-ith the A uncl C. Although the st'squioxides are more n,\nmdu.nt Hum silicl1 in the B 2 Iayt'r, no Yery reg'uln.1' fructionution is iudien.tt'd by the .iron o}.-ide alumina, ratios. '1'he irrl:'g'ularity is d1l(, for the most pn.rt to the tend('ncy of iron oxick t,o spgregai(\ into soft, ('olH'rt'tiolls at various lev('1s in the soil profill', n.nd th('y Me only partially (lispersed as colloid in the lai>oru,tory S('PILI'II.tiOIl of t 11(\ ('olloid from the soil. Alumiult, howr,,{'(', is J'('1n.tivply lIIort' n.\HlIldullt in the B2 layer than in. the bleached layer (A2) ('xc('pt ill. the (\xtrt'Il101y well developed t Podzol, the BrnSSUt1. It ulso muy be noted t1ULt the blen.ched layer 48 TECHNICAL BFLLETIN 609, U. S. DEPT. OF AGRICULTURE characteristic of the typical Podzol fades out or diffuses into other layers in the more southerly Gloucester soils. The latter are, therefore, placed in the group of Gray-Brown Podzolic soils by Marbut (25) in spite of the extreme fractionation of the colloids. .Although it may not be evidence in point, it is interesting to note further that the colloids showing extreme fractionation in the profile are from soils developed on glacial drift; the difference with respect to the age of the two drifts, however, is not so evident. In the colloids of the southern group, the ratios of silielt to sesqui oxides and to alumina, as ,\ ell a,s the ratio of iron to alumina, seldom \"a1"1 more tban 10 percent from the mean of the profIle. Greater eluviation of iron oxide has oecurred, however, in the Chester and Manor than in. the Appling aDd Cecil profiles. It has not (as might he e)..-pected) lodged in the B byers of th\.J Chester and Manor and .. Cecil as it has in the Appling but has passed to the C. r~aterization is evidenb in all four profiles, but more so ill the Cecil find Appling thaD in the Chester andl\lmwr. These relatioHs undoubtedly have a mttrked effect on the comhined water. " The combined wn.ter of the southern group of soils does not V{l,ry greatly within en,ch profile. The eombined WItter of the soil aeid, both in aIDolmt an(l in proportion to silica, the sesquioxides, and alumina, does not depart from each profile average, in any layer, by more than 15 percent, a,nd usually the difl'erenee is much less. As e:\.-pected, the water-iron oxicle mtio Yal'ies eOllsiclerablYi nt the lowest levels of the Chester fi,nd :Mu,nor it is about one-hnH the value of the A layers; but the difrerellee is much lrss in the Cecil nnd Appling. The com bined water of the soil lll'id is slightly less in the illuyjated layer of the M~anor find the Chester soils than in the A OJ' C, but in the Cecil it is greater in this b)rpr thttn in the C, 111l(1 ill the Appling it is greater there than in the A 01' C. .., Extensive changes ill the ('olltellt of ('omilillf'c\ wfl.tt'r, and necessarily of the husps, have taken plnce in tlw coUoid ('olllplex durillg the fmc .. t.ionatioll of the ('olloids of the {om podzolized 110rtJwfll soils. In the Podzols, the formula mtio of siliea t.o hases is uhout 20 in the B 2 1ayer, 15 in the A2, [lnd 5 to Gin the C. The varintion in the two Gloucester soils is not so marked. The e0111bil1('d bases in the last column of -1 table 31 indica.te 1(,8S extellsiyc len.ching of the Gloucester colloids. On the other hund tho extremely low hase content of tIle colloid of 4.1 the B2 layers of the Podzols assures eX'i,reme leilching of the material J eluvintf'd to tli('se Iny('r8. Tl](-\ comhined w!tter, fiS well as the eom hilH~d water of the soil a.cid, 111ay be t\\TO or three times greater in the B 2 layer than in the A or C. This is eaused by the extreme hydra tiou of the colloids which ewmtually find thf'ir WRy to the B2 In,yer. ~ The wn,ter-sesquioxi(/e, the water-alumina, and the water-iron oxide ratios reflect additions of comhined WIlt-f'I' in the eolloid of aU the soils. With few exceptions these l'lltios are, of course, great('r in the B 2 1n.ycr than n.bove or helow it. The variation of frpo iron hydro.xide (always ~ present in the Podzols) eontrihutps to the variation of the water ratios. It is evident that hydration of the. colloidal portion of the profile of the Podzols has beon extreme. High soH acidity, an abundnnce of organic matter, thorough leaching, n.ncl the permeability of the soil have contributed to extreme hydration of t11e clllY minemls n.ud the segregation of different fmctions Ilt vuriOlls levels. Visual evidence 1 of the alteration of the profile is shttrply defined ill the J)odzols only, PROPERTIES OF NEW ENGLAND AND PIEDl\fOXT SOILS 49 but the composition of the colloids indicates a remarkable similarity of .all four profiles, irrespective of tbeir morphology. The causes of the remarkable profile similarity of the colloids of the Brassua, Hermon, the Gloucester from Ivfassachusetts, and the Glollcester from New Jersey are doubtless the similnrity of the climate, vegetation, and parent material. The forest is coniferous. The parent materiul is glacial drift. The mean annual temperatme of the Brassua and Hermon is 43° F. and that of the two Gloucester soils is 48°. The mean annual rainfall of the Bmssua, Hermon, and Glouces ter from 1fassu.chusetts is 39 inches, that of the Gloucester of New Jersey is 10 inches greater. The variation of climatic condiliions with out doubt causes minor differences in the composition of the colloids, but the parent material is c('rtaiuly chiefly responsible for the remark able similarity of the colloids of equivulent hOlizons of this group. The chemicu'! composition of the colloids within the profile clumges immecliu.tely after passing southward beyond the bordNs of the glacial drift. Although differences in morphology pla,ce the Chester and Manor series in the group of Gmy-Brown Podzolic soils with the Gloucester, the composition of their colloids indicat('s that they are more closely related to the Oecil and Appling seri('s belonging to the Red and Yellow In,telitic group of soils still farther south. The com position of the colloid does ]lot show m!Lrked chang-es within the profile fractionation of the colloids is slight, and debasement is not extreme. The wlLter-alumina ratio of the colloid deserves special attent.ion, as it is the leust vnriable relationship considered. 11:utual dependence of alumina nnd wfI.ter in the colloid composition appears ('('rtain. The averuge values of this ratio for the profiles of t.he Clwster, 1\1anor, Cecil, and Appling colloids are 2.33,2.39, 2.38, and 2.31. They are, in fact, lleaTly constant. Within ench profile they nre 1110re variable, however, but the variation from the mean in eHch is slig-ht. These ratios present a sharp contmst with those of the Brl1sslUt, Hermon, t.he Gloucester from 11assachusetts, and the Glou('('st('l' from New ,Tersey, whose profile averages are 3.16, 3.30, 3.13, and 2.G4, l'f'spec tively. The gmnd avern~e of tIl(' southern group is .2.:33; thnt of the " northern is 3.04. The efl.UsC of the similarity of the colloids of tIle four southern soils r is evident. They are all l()cu.ted beyond the hOI'(I('l"s 01' the glacial drift. The plLrent miltelial is ess('ntiully the SILnH'. The l11('an u.nnunl ( temperatme of the C'hest('\' and 1fnJlOl' is 54° F. tLnd or tIle Appling and Orcil about (jOo. 'rlw mean nnnual millInU of the fil'st two is about 40 inches; tlllLt of the lust two is 50 inch('s. ,rith gPlleml con ditions so much lllike similarity of t.he colloids 1'eslllts. The minor individual differences are In.l'g('I)~ due to local ellyironment.. A statistienl rxaminntioTl of th<1l"plntionships of the silica, f11I1mina, and water of the colloids is of intt'l'C'st. ThC' cOlTC'llltion coefficients were calculated by the m('thod def;Cl"ibed hy Tollev and 1\Jendum (42). Although nil the possibl(:\ l'plntionshiJls firc l\(lt accounted for, and the mutual dependence of the pJin('ipal cOll<;tituPIlts mn.)' be more implied th!1Jll"eul, the eOrt'elntion ('o('flieients am suggcsti,Te of possible conditions. If one ('onst,itu(,llt Yluies c1il"C'ctly and p('rf('ctly with another, the cOlTelatioll e(){'flicieut is +1.0; if it is 0.0, th(,l"e is llO cor relation, no mutual dependence; nIld if the Yarintioll is inverse find t perfect, it is -1.0. 50 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTLTm~ The correlation coefficients, calculated from the datu, from 41 hori zons of the 8 profiles presented, are suggestive of the profound pfTect of water on soil formation in a humid climate. The correlation co efficient of water to alumina is +0.71; water to silica, -0.55; and alumina to silica, +0.04, indicating that the rplationship of water to alumina is close; of water to silica, inverse but less perfect; and of alumina to silica, not significant. Therefore as the primary alumino silicates of the soil nre decomposed, Jlydmtcd secon determining the fmal composition of the various soil colloids. The proper evaluation of their effectiveness is doubtless impossible, but certain relationships may be pointed out. The colloids of the four soils derived from glacial drift have experienced considerable f'rac tionation; those derived from older parent material south of the drift have not. The vegetation is largely coniferous, the parent rocks are largely gmnitic, and the rainfall is about the S{lme for all. The tem perature, however, is variu,ble. Presumably the abundance of organic mn,tter has helped to JraetiOl1o,te tlle llydl'olytic products deri\'ed from the relatively young hut filWly c0ll1111illutrll gln.ein.l drift, and it also has fLceentuu,ted ll:nlrolysis. But farther south the pn.rent matel·itt) is older, rock dl:'eompositiol1 is morc compll:'te, and the orgouic matter is less abundant. Very little frnetiolliltioll of the colloid, therefore, has oecuned. Yl:'gl:'t.n.tiOll hns not }){,I:'ll able to produce violent changl:'s in the colloid:; of the bal:'l' group of soils, both because of its insuHiciency and the resistarlee ofl'el'ed by an exceedingly stable an<"ient colloid. Theoretical considerations for the formn.tion of soil colloids Lave been outlined by llYNS (12). It is a,:;slll11e<.l that the pl'incipal colloid forming process is tlle hydrolysis or the (Tyst:dline ],ocks, or their secondn,!,)T prod uds, and thn,t the proCI:'SS is governed by environmental conditions which ]'eguittk.its intelw,ity and extent. I t is t),ssumed that the fundlLI11l.'ntn.l pn,rt of the colloid cornpl('x consists of dcfinite fLffi phote1'jc nlumillo-sil.icie "adds." The soil colloids thl:'l11scl\'es nrc n.ssumed to be the salts resulting from titr. l1cutrnlizu.tion of the odd nnd basic cOllstitul:'lIts of thpsp Ilcids. Iron is asslI!lwd to belJlwc essentially u.s aluminum except that its ('Ornl)(]lllJ(ls n,1'e more readily decomposed and it exists in lli~.ddy hydl'olyzl:'d prod uds as the hy droxide or oxid('. Tbe possible ('Xi"t,(,llce of till:' following compounds is assuml:'d (10,11,12,13): 3}-I20·Ab03·fjSi02 (montmoril1onitic acid), 3H10·.Al~OsASi02 (py]'ophyllie acid ),:iH~O·Al~03·2Si02 (lmlloysitic acid), 3H20·.AJ:?03·1SiO;l (nllopbn.nir Heid), tlTld :3Jr~O .•\1203 (nluminum llydroxitll:'). Although a giYl:'l1 rolloid m:\.y h0 dominH,t.('d by one of thes(', it is not l'('u,sonnbl('. to e:\j)(>ct tbat un inorganic: ('olloid would consiht whollv of H-llV one of tlll'se ucids. ~rn,l'sbnll (2(;) nssulll(,S the ('Xistt'll('('. of u, more· extcllsive group of r du.y min(,l'f11s thn,n the few just IIIPntiollPd. Awong th('f;p, beidellite has nil fl,ecpptC'd fOl'lllUh ratio of 1l]JiL\1~03.3Si02' in which vurlous repln,ccl1wnts of nlumillUI11, silicon, nutgrwsi1111l, nncl iron ma.y take r pllLee. He emphnsizl:'s the irnpol'!nncc of the httier. stl'lleture of the dny minera.!s. Bmy (8) n.lso nSSlIlIll:'S the presence of beidellite in the colloids of <.'Ntn,in Illinois soils. The rom;tmJ{'Y of ('ompm;ition of tIl(' colloids of tho soils south of the dl·in suggests the possihility tlHtt th<,y a 1'0 eomposecl, for t,lle most purt, of Ollt' or a 111L'(tUI'e of the f-\uggl\skd nlullIino-silicie "adds" or Uwir sults, nlong with 1'l:'rrir oxidp. 1n tho Podzols, how('\,er, t.he ('ol1oid eOlllposition suggests a pl'Obnhll:' mixturo of lllumino-siHelltes of highor Biliea-tllllUUnn, 1':1tio logl'th('I' with 1'01'1'ie hydroxide ill t.he B horizons. The sim110l'i ty of the ('olloid eOIl1J)osi 1ion suggests that t during tl'nnslocn tiOll (,BS('1l tinlly lilw ('olloi(1s htl YO b('(\11 S(\g'I'('gnted in ('.ertllin lUYNR. 1t might be nssulll('(l, tl!l'l'dol'(', thnt, 11, fl:'\\' compounds likew-isc cOllstitute t\;(\ priJl('ipal pt\.l't 01' Ow eo]Joiu ('.olllplex of like horizons of the Pouzols. 52 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE The three principal constituents of the conoid, constitutional water, alumina, und silien., represent about three-qua.rters of the colloid by weight. In order to bring into bold relief the various contrasts and theoretical considerations tha.t the relationslllps of these three com ponents offer, the formula-weight ratios are presented in table 32, along with other pertinent datn.. In these rutios alumina is taken as unity. Data from ('('rtain important horizons, identica.l with those in table 29, W('I"(\ sp1eeted fot· comparison. Tho formula. weight ratios suggest a dirpct eOlllpal"isOIl wilh the various soil acids previously mentioned. T.~BLE 32.~RelaUotlS bel-wf'en /e1l1 ])('ralll.r, minfall, and 1JToporiions of Al,03. SiO" and flJi in r()lI()i".~ from "('r/nin hOr7:;;on.~ I of t'U1"iOIlS I'oils Formula ratios or the :a;l['~~~l ~'kln ---- Soll series l Cil'neral loentitm ! tplU- ,:.u.lJ~tJul r \ ltori/ou B lwrizon (" horizon : pl'ra- [ f:Il!J- ~ ,_~ ___.~~ I ~ tunl ' f:lll I ; lJ,tl ..\1;0 :';0, . .1 reO . AJ,O,: SiO, : 11,0 . AbO,' 8iO, ; : _,__,__:__1_ Brassu!L._.... Xew Hump· I . 3.·11 : :1. r.2 1 0.81 j 2. (;31 1 1. 80 I sbire. ! ! Hermon...... ~ . lIo .. _~ ... ' ~. ':: ·3~.· "t':! 1 ~ . 7r. . 3 r~J ! 21., Gloucester 1l\.[n""at'bllseLL~~ ~ , _ " " I!.7a . 2."1 . !2~ Do. _~.' ~, "ew Jersey~ •. ~., , I. 7~ 2 ',I 1.,:; i 2. a~ I 2.09 Chester-. , ll\.rnr)·l~nu... I, , ~. :j;l 2. ·H 1 i 2. -t2 ; 2. -I-t 1 2.25 Mnnor,_ .... \lr~lUla,,~ ~ : i :! :: 1 i 2 :!..... 1 : ~. :!fi :!.4G 1 ,: 2.10 CeciL _ ~ !'\orth Carhlina t J {,:,) , ~ :!;; 1 I 1. ",5 I ~. 1;-, 1 1. 95 APIJli!Jt! nl'orzin~_ : 2 1;1 . 2 ~5 ' J. 1 liij .' 2. 13 'I I 1. S3 J __~__-'--_.'--_ I Surne a~ in tuhle ~J. In the fOl'lllula-wright ratios ill tuhlr 3:2 watN is much more eonstant than silica. ill fill tbe ]>l'ofilt's. ('OllstUllCY of combined ,\'nt('r ill the .A horizon is not C'xpcet('d. Errors illtrodue('d by the qualified values for a high orgunic Jl1att(,l" COlltPllt (1) amI the tcndency of the surface colloids to drbydrate during pNio the surface layer of the New Jersey Gloucester, in the Band C layers of the Appling, all hm1.zons of the Cecil, and the C layers of the Brassua and Hermon, since the silica-alumina ratios are less than 2. Values for silica of less than 1 for the formula. ratio of the B colloids of the extremely podzolized glacial soils suggest a mixture of allophanic acid and aluminum hydro}':ide. Excess water above the value of 3 also indicates that a part of the alurruna is free and uncombined with silica. Dehydration of the colloids is probable, however, in the more southerly situated group of soils. Taken as a whole the data on the eight soils studied seem to warrant the following general cOllclusion: The properties of these soils and their colloids depend on. all the environmentnl factors which have operated to produee them. Yet it is not possible to assign a primary role to anyone of them. It has become mther usual for soil scientists to regard parent material as of secondary importance in soil forma tion in hurrrid climates. The datu, presented show the effectiveness of parent matm1.nl Dl resistDlg the forces operating upon it. In emphasiz ing this point the writers nre not ignoIing the parts played by rainfall, temperature, and temperature changes, the kinds and quantity of vegetation, age, and topography. In reaching conclusions concerning soil production all enviromnental factors must be considered. SUMMARY Eight profiles of Roils derived from gmnitic materials from New • England and the Piedmont hnye been studied. The areas in which the soils developed have a mean anIlual temperature range of 43.0° to 62° F. and a mean anJ1ualrainfall range of 38 to 50 Dlches. The description of each profile Dlcludes information concerning parent material, vegetation, and climate, and is preceded by a ~eneral deseIiption of the soil series. The laboratory determinations mclude pH values, soluble salts, mechanical and cherrricn.! analyses of the soil, cherrrical analyses of the extracted colloids, and the water vapor absorbed by them at 99-, 75-, and 50-percent humidities. ~ The analytical results and del'iYcd datn" arranged in tables, are discussed in c0Ill1ection with the chemical und other characteristics of r each profile as affected by climate, vegetation, drainage, etc. This is followed by a genernl discussion of the relationships of the whole group, a,ccompillued by tables of summnrizing duta beming on the r composition and constitution of the colloids. I It has been shO\nl, that the colloids of' soils derived from glacial drift have been fractionated extrcmely during pl'oijle development; those derived from older parent material have not. The Brassua, Hermon, and two Gloucester soils are highly podzolizecl; the Chester, Manor, Cecil, and Appling nre In teritic. The dominant soil-forming process of each group is hydrolysis; it is influenced by the parent material and intensiHed by {Ul incl'ense in tIle mean mmual temperature. Extreme variation of the colloid composition in the profiles is not alwavs indicated by the morphology of the soil. It has been show11 thnt the curbon-nitrogen ratios of the Gray Brown Podzolics und lftteritic soils and their colloids usually decrease with depth. The .rutio is us high as 45 in the Podzols, and lower than 10 in the colloids of some of the jntcl'itie soils; the ratio for the colloids is usunlly much less thll,U that of the soils. Its use as u. factor is obviously doubtful. 54 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE The colloids of the B layers in geneml absorb more water vapor than those of the A or 0, but the hygroscopicities approach the same values at the lower humidities in all but the Podzols. At 75- and 50 percent humidities the water vapor absorbed by the colloids of the more southerly soils is less than that absorbed by the collLlids farther north. The ratio of water absorbed at 99- and 75-percent humidi ties is indicative of the great soil groups. From north to south for each profile the average is: Podzols, 1.77 and 1.45; Gmy-Brown Podzolics, 1.96, 3.27, 2.71, and 2.85; the lateritics, 7.38 and 5.80. At low humidities the ratios approach uniformity. The average is l.39. Itis inferred from the data that the following soil acids identify the colloids: theA horizon of the Podzols,pyrophyllic acid; the surface layer of the Gloucester from Iv[assachusetts and all layers of the Chester, Manor, and Appling, hnlloysitic acid; the surface layer of the Glouces ter from New Jersey, the B l1Jlel C layers of the Appling, ull horizons of the Cecil, and the C layers of the Podzols, ullophanic aciel. The presence of free alumina, is indicated in the B layers of the podzolized glacial soil colloids. In the soils of the New England and the Piedmont, envirollmental conditions tend to produce colloids of a wide range of composition. Parent material, temperat.m·p, rainfall, and vegetat.ion are the prjmary factors aiTecting the composition of the colloids. LITERATURE CITED (1) ALEXANDER, L. T., and BYERS, H. G. 193-2. A CRI'rICAL J.AllORATORY HEVIE\\, OF lIIETllODS 01' DE'l'ElRMINING ORGANIC MATTER AND C.I ItBONATES I~ SOIL. F. S. Dept. Agr. Tech. Bull. 3] 7, 2G pp., illus. (2) --- and BYERS, H. G. 193G. HYDItOLYSIS OF CALC'lUM ]tELDSPAIt. Amer. Soil Sun'cy Assoc. (Rept. Ann. Meeting Hj) Bull. 17: 21-23, illus. (3) ANDERSON, M. S. 1929. THB INFLUENf'E OF S~TllS'fT'rTITED CATlONS ON THE PROl'ERTIBS OF SOIL COLLOIDS. Jour. Agr. Hesearch 38: 565-584. (4) --- and BYERS, H. G 1931. CHARACTER OF THE COLLOIDAl, MATERIAl,S IN 'flU] PROFILE OF CERTAIN MAJOR SOIL GROL'PS. t', S. Dept. Agr. Tech. Bull. 228, 24 pp. (5) --- and Bnms, H. G. .(. 1934. 'I'Hli) CARBON-NITROGElN RATIO IN UBLA1'lON TO SOIL CLASSIFIC.~TION. Suil Sci. 38: 121-138. (0) BAU,EY, E. H. J \ 1932. THE EFFECT OF AlIt DUY!NG O~ THE HYDROGli)N-ION ('ONCENTRATION OF SOILS 01" TrrEl UNI.TE]) STATES AND CANADA. C. R. Dept. Agr. Tech. Btl1:. 291, 44 pp., mus. (7) BALDWIN, H. I. 1936. FAI,r, OF BROWN SNOW IN NEW HA1.1PSHIRE. ScieIlce (n. s.) 83: 371. (8) BRAY, R. H. 1937. CHEMICAL AND PHYSICAL CIIANGElS IN SOIL COLLOIDS wrIll ADVANCING DEVEI,OPlIfENT IN ILLINOIS SOILS. Soil Sci. 43 (1): 1-14, illus. (9) BROWN, I. C., and BYEItS, H. G. 1932. THE FItACTIONA1'ION, COMPOSITION, AND IIYPOTHETICAI, CONSTITU TION OF C'BrtTAIN COLLOIDS DEHIVED FItOM 'fHE GREAT SOIL GROUPS. U. S. Dept. Agr. Tech. Bull. 319, 44 pp. (10) --- RICE, T. D., and BYBRS, H. G. 1933. A STUDY m' CLAYPAN SOILS. U. S. Dept. Agr. Tech. Bull. 399, 43 pp. (11) --- and BYERS, H. G. 1935. THE CHEMICAL AND PHYSICAL PROPERTIES O~' DRY-I.AND SOILS AND OF THEIR COLLOIDS. U. S. Dept. Agr. Tech. I~ull. 502, 56 pp. ; PROPERTIES OF NEW ENGLAND AND PIEDl\IONT SOILS . 55 (12) BYERS, H. G. 1933. THE CONSTITUTION OF 'I'HE INORGANIC SOIL COLLOIDS. Amer. Roil Survey Assoc. Bull. 14: 47-52. (13) --- ALEXANDER, L .. 'I., and HOLMES, R. S. 1935. THE COMpOSl'rION AND r:ONSTITUTION OF THE COLLOlPS OF CERTAIN OF THE GREAT GROUPS OF SOILS. U. S. Dept. Agr. Tech. Bull. 484,39 pp. (14) --- and ANDERSON, M. S. 1932. 'J'UE COMPOSITION OF SOIL COLLOIDS IN REJ~A'l'ION TO SOIL CLASSIFI CATION. Jour. Phys. Chem. 3G: [348]-36G. (15) CUSHMAN, A. S. 1905. '£IIE E~'FECT OF WA.TER ON ROCK POWDERS. D. S. Bur. Chem. Bull. 92, 24 pp., illus. (16) --- and HUIlIlARD, P. 1907. THE DECOMPOSITION OF THE FELDSPARS. U. S. Off. Pub. Roads Bull. 28, 29 pp., illus. (17) FOLLETT-SlIUTlI, R. R. 1935. REPORT OF THE CHEMICAl, DIVISION Fon THE YJo}AR 193·!. Brit. Guiana Dept. Agr. Divisional Repts. 1934: 81-101. (Chern. Abs. 30: 3559.) (18) FREISE, F. W. 1936. ASSOCIATION OF 'l'HE FORMATION OF KAOLIN AND ALUlIIINA FROM GRANITE AND GNEISS. Chem. der Erde 10 (3): 311-342. (19) HILGAUD, E. W. 190G. SOILS, TUEIRFORlI!ATION, PROPEltTIES, COMPOSITION, AND RELATIONS TO CLIMATE AND PLANT GROWTH IN THE HUMID AND ARID HEGIONS. 593 pp., illus. New York. (Reprinted 1918.) (20) HILLEBRAND, W. F. 1919. TIlE ANALYSIS OF SILICATE AND CARBONATE ROCKS. U. S. Geol. Hurvey Bull. 700, 2S5 pp., mus. (21) HOLMES, R. S. 1928. VAlUATIONS OF ,)"Hl~ COLLOIDAL lI[ATElUAL IN TYPICAL AREAS OF THE LEONAIW'I'OWN Slur LOAM SOIL. Jour. Agr. Research 36: 459 470. (22) --- and EDGINGTON, G. 1930. VAlUATIONS OF 'I'HE cor,I,OWAL lIIA'I'EIUAf, EX'1'RACTED FROM THE SOILS 01' 'I'HE MIAMI, CllES'I'EU, AND CEClT~ SERIES. U. S. Dept. Agr. Tech. Bull. 229, 24 pp., ilIus. (23) KELLOGG, c. E. 1930. DEVEI,OPlIIENT AND SIGNIFICANCE OF THE GREAT son, GROUPS OF THE UNI'rED STATl!]S. r. H. Dept. Agr. Misc. Pub. 229, 40 pp., mus. (24) LEIOHTY, W. R., and SnOREY, E. C. 1930. SOME CAHnON-Nl'l'UOGEN RELNl'IONS IN SOILS. Soil Sci. 30: 257-26G. (25) MARnuT, C. F. 1935. SOILS OF THE UNl'rED STATES. In A'1'LAS OF AMERICAN AGHlCULTURE pt. 3, AclvlLl1CC Sheets no. 8, 98 pp., illus. (26) MAUSHALL, c. K 1935. THE nll'OHTANCE OF THE LA'rTlCE STUUCTUUE OF THE CLAYS FOR THE S'l'UDY 01<' SOILS. Jour. Soc. Chem. Indus. 54: 393-8T, illus. (27) MATTSON, S. 1930. 'rUE I,ll. ws OF ('or,l,OIDAL lJEUAVIon: Ill. ISOELECTlUC PUEOIPITATES. Soil Sci. 30: '159-495, illus. (28) !lbimILL, n. P. 190G. HOCKS, nOCK WEA'1'HEIUNG AND SOILS. Ed. 2, 400 pp., iIlus. New York. (29) MIDDLETON, H. E. 1928. 'rIlliJ ADSORPTION OF WATER VAPOU IlY SOILS AND SOIL COLLOIDS. First lllternatl. Congo Soil SeL, \OVashington, 1927, COIIlIl. 1, Proc. and Papers]: 446-'155, illus. (30) --- SLATEU, C. fl., and Bn:Hs, H. G. 1932. PHYSI(,AI~ ANI} (,HEMWAI, C'IIARACTErtISTICS OF SOILS FROM THE rJltOSION I,XPliJl([lIlEWI' R'I'ATfONS. F. S. Dept. Agr. Tech. Bull. 3W, 51 pp. (31) --- Sru\'l'BU, C. S., and Bnms, H. G. 1934. THE 1'IIYSICAI, AND ('IIIJMICAL CIIAHA(,T~)mS'I'ICS OF 'rifE SOILS FltOM 'I'Hffi EROSiON ffiXI'~11t1l\!ENT f:l'rA'rlONS-SECOND UEPOHT. U. S. t Dept. Agr. Tech. Bull. 430, 63 pp., illus. 56 TECHNICAL BULLETIN 609, U. S. DEPT. OF AGRICULTURE (32) NEUSTRlWV, S. S. 1927. GENESIS 01' SOrL,~. Acad. Sci., U. S. S. R. Russian Pedol. Invest. 3, 98 pp. Leningrad. (33) OLMSTEAD, L. B., ALEXANDER, L. T., and MIDDLETON, H, E. 1930. A PIPETTE METHOD OF MECHANICAL ANALYSIS OF SOILS BASED ON III1PROVED DISPERSION PROCEDURE. U. S. Dept. Agr. Tech. Bull. pp., illus. 170, 23 1 (34) RAlIIANN, E. 1911. 1l0DENKUNDE. Eel. 3, 619 pp., illus. Berlin. (35) ROBINSON, tV. O. 1922. THE ARSORPTION OF WATIm BY SOIL COLLOIDS, .Jour. Phys. Chern. 26: [(j'17J053. (36) 1930. ~IETUOD "\ND 1'ItQCEDURE OF SOIL ANALYSIS USED IN 'l'H8 III VISION OF SUlL CHEMISTHY AND l'fIYSlCS. l', S. Dept. Agr. Cir. 139, 20 pp. (37) 1930. COMPOSITION AND ORIGIN Ol' DUST IN THE FALL O~' BROWN SNOW. N. H. IWci Vt. Monthly WeD,ther He\'. tH: 86. (38) --- EDGINGTON, G., and BYERS, ll. G. 1935. CHEMICAL S'rUDIES OF INFERTrLE SOILS D};H1VED ~'ROl\! ROCKS HIGH IN l\l,\GN8S1UlI! AND GENERALLY llWH IN CIIHOIl1IUM AND NICKEL. r. S. Dept. Agr. Tech. Bull. 471, 29 pp. (39) --- ami HOLMES, R. S. 1924. ~'1U~ CHEmCAL COMPOSITION OF' son, COLLOIDS. U. S. Dept. Agr. Bull. 13U, 42 pp. .~ (40) R UBSEL, R. D. 1936. THE MINERAL CO,\II'OSITION OF ATlIlOSl'HEHIC Dus'r COLLECTED AT BATON HOUGE, LA. Amer. .Jour. f)ci. (ij) 31: 50-66. (41) SMOLIK, L. 1930. llUlIllFlCATION IN C["LlC,\TO(;]'JNJ(' SOIL '1'1' 1'~:S. Shornik CeskoHlov. Almd. ZelJledelske 2: 93--1OJ. (42) TOLLEY, H. R., alld MENDt:TlIl, S. W. 1924. A lItE'l'lIOD OF TESTINO FARM-MANACa':MEX'l' AND ('OBT-O~'-PRODUCTION DATA l'on YAI"IDITY 01,' ('ONCLl'SIONS. l;. S. Dept. Agr. Dept. Cir. 307, 13 pp., illus. (43) IVAKSII1A:-<, S. A. 1936. IIUlI! 1!S. 49·1 pp., illus. HuJtimore. r v .1 t I 1 ,"