Johnson County, Missouri - Chapter 36: - Soils, 1918

Robertsville Silt Loam

General Geography. - Jolmson county is situated in the residual prairie section of tlie Great Plains region. Tlie county is roughly rectangular in outline and has a length from east to west of 3>3 miles and a width from nortii to south of 25 miles. Its area is 831 square miles, or 531,840 acres.

Johnson county comprises two physiographic ili\isions - the upland and the lowland. The upland comprises about nine-tenths of the area of the county. Topographically, it is rolling ratlier than level or undulating, althougii areas of considerable extent are comparatively le\el.

A central belt and the southeastern and soutliwestern parts of tlie county are somewhat smoother than the remainder. The central belt includes the immediate valley of Blackwater river and a lowland belt adjacent to it, especially the country lying northeast of Warrensburg. The lowland belt is developed on a bed of soft shales lying beneath a series of more resistant limestones which form the adjoining higher country to the south, the limestone outcropping along the southern l)order of the lowland at the top of a low but well-defined escarpment. The soutliwestern smooth area is likewise developed on a bed of soft shales, which is higher than that forming tlie central belt. It lies in front of an escarpment which liarely enters the western part of tiie county, and which constitutes the eastern boundary of a high plateau in Jackson and Cass counties. The smooth area in the southeastern part of the county extends over a series of limestone beds. It is a low plateau, over somewhat resistant limestone, which has not yet been dissected.

The upland soils are of residual origin and are derived from the immediately underlying rocks, which belong to the Pennsyh'ania division of the Carboniferous and consist of alternating strata of limestone, shale, and sandstone. Geologically the county is made up of the Cherokee shales and sandstones, the Henrietta limestones and shales, the Pleasanton shales, the Bethany Falls limestone, and the ^^'arrensburg sandstone.

The Cherokee shale lies in the extreme southeastern part of the county and in the Blackwater lowland belt and consists chiefly of shale and sandstone. The shale of this formation gives rise to the Oswego and Cherokee soils.

The Henrietta limestone occurs in the southeastern part of the county west of the area of Cherokee shale. It forms conspicuous ledges in that vicinity. The limestone gives rise to the Crawford soils.

The Pleasanton shale is the surface formation in the western part of the county. The formation consists of about 175 feet of shale and sandstone, with one or two thin beds of limestone. The shale gives rise to the Summit soils. The Pettis silt loam is derived partly from the interbedded limestone and shale of this formation.

The Bethany Falls limestone occurs in the northwestern part of the county, forming a distinct but ragged escarpment along the streams. It gives rise to the Crawford and Pettis soils, the former being derived exclusively from limestone, while the latter contains considerable material derived from shale.

Sixteen soil types, representing 10 series, are mapped in Johnson county. The residual or upland soils comprise about 85 per cent, of the total area of the county and include the Summit, Pettis, Crawford, Boone, Bates, Oswego, and Cherokee series. The soil material in some places has a depth of 30 feet or more, the greatest thickness occurring where the softer shales underlie the surface. The Summit, Oswego, and Cherokee soils are residual largely from shale, which is calcareous in case of much of the Summit: the Crawford and Pettis soils are residual from limestone, with some shale material in the case of the Pettis; the Boone soils are residual from sandstone and shale, and the Bates soils from shale and interbedded sandstone and limestone.

Following are brief descriptions of Summit series: These soils are residual in origin and are derived from shales and limestones. The drainage is good and the topography smooth to undulating. In Johnson county two types of this series are recognized, the silt loam and the silty clay loam.

Summit Silt Loam. - The surface soil of the Summit silt loam, where typically developed, consists of a black silt loam to a depth of 15 inches, below which it grades into a silty clay loam of a somewhat lighter color. The subsoil, beginning at a depth of 24 to 26 inches, is a heavy clay of dark-drab color. The line of demarcation between the surface and subsurface soil is rather indistinct, but the gradation into the clay subsoil is usually sharp.

Small eroded areas of the Summit silt loam occur in a few places in the northwestern part of the county. They are locally spoken of as "deer licks," and support little or no vegetation.

This is the most important and most extensively developed soil tvpe in the county, covering an area of 228.5 square miles. It occurs mainly in the vicinity of Kingsville and in the northern half of the county.

In general the Summit silt loam occupies the smoother areas of the county. It occurs on the tops of ridges and on lower level stretches surrounded by escarpments of limestone outcrop. It is generally sufficiently rolling to have good surface drainage, although the character of the subsoil does not permit a maximum absorption of water. It is locally referred to as "black limestone land," probably because of the frequent outcrops of thin limestone beds along streams.

Practically all the type is under cultivation. It was originally prairie and was very rich in organic matter when first cultivated, owing to the heavy growth of prairie grasses that had covered it.

Owing to the plastic character of the subsoil, this type is rather cold and wet in the spring, and on this account the seeding of crops is frequently delayed. While most of the type is in fair physical condition, continuous cropping without adequate provision for the maintenance of the organic matter has brought about a condition of poor tilth and a decrease in crop yields on many farms.

Summit Silty Clay Loam. - In its typical development the surface soil of the Summit silty clay loam is a dark-gray to blackish silty clay loam, black when wet. This grades at about 15 to 18 inches into a drab to grayish-brown claj^ In many places the type occurs in narrow strips at the foot of elevations, sometimes extending considerable distances up the slopes. Usually such areas are poorly drained, and the soil approaches a clay loam in texture, frequently being referred to as "gumbo" land.

Pettis Series. - The soils of the Pettis series are brown to dark brown in color. These soils are residual from shales and the topography is smooth to undulating. One type, the Pettis silt loam, is recognized in Tohnson countv.

Pettis Silt Loam. - The Pettis silt loam typically is a very dark brown to black, mellow silt loam to a depth of aljout 18 inches, Ijelow which it grades into a slightly lieavier silt loam of dark reddish l)rown color. At 25 inclies the subsoil is a l)rown silt loam to silty clay loam, which continues to a depth of 36 inches, becoming slightly heavier in the lower part of the three-foot section. It occupies the level tops of ridges, the topography being more rolling than that of the Summit silt loam. This type differs from the Summit silt loam in having a much more friable subsoil and a lighter color. The tvpe is spoken of locally as "mulatto land." It is considered one of the most productive soils in the county. Its deep, porous nature makes it especially drought resistant, and it is easily maintained in a condition of good tiitli.

Crawford Series. - The Crawford series comprises residual limestone soils of the prairie regions. They are derived from limestones, often with more or less material from shales. In this county only two members of the series are recognized, the Crawford silt loam and stony loam.

Crawford Silt Loam. - The Crawford silt loam consists of a red or reddish-brown to brown silt loam, underlain at depths of 12 to 18 inches by a reddish-brown silty clay loam. .At a depth of about 27 inches the subsoil grades into a red, crumbly clay, whicii extends to a deptli of 36 inches or more. In places along slopes l^edrock is encountered within the three-foot section.

This' soil is found in practically all parts of the county, but there are no extensive single areas. It occurs on the tops of ridges underlain by limestones.

Crawford Stony Loam. - The surface soil of the Crawford stony loam is a dark reddish brown loam, usually e.xtending to a depth of about si.x inclies. The subsoil is a reddish-brown to red clay extending to a depth of 36 inches or more or to the underlying limestone.

The Crawford stony loam occurs along steep slopes and along the outcrop of the Bethany Falls limestone in the western part of the county and that of the Henrietta limestone through the eastern part of the county.

Boone Series. - The soils of this series are of residual origin, being derived from sandstones and shales, principally of Carboniferous age.

The topography is roUing to steeply sloping. The Boone soils are closely associated with the Bates, but differ from them in containing less organic matter and in being consequently lighter in color. In this county three types of this series are mapped - the Boone silt loam, fine sandy loam, and gravelly loam.

Boone Silt Loam. - The Boone silt loam consists of a grayish-brown silt loam, underlain at a depth of 5 or 6 inches by a layer of gray silt loam. At 15 to 18 inches a yellow-gray to grayish-brown silty clay loam is encountered, and this grades at about 2S inches into a friable clay. This soil is quite variable in texture, especially where it grades into the fine sandy loam.

The Boone silt loam has a wide distribution, occurring along all the streams of the county. It is extensively developed from the vicinity of Warrensburg to Knob Noster and Henrietta. The topography is rolling to hilly along some of the streams, notably along Clear creek.

All of this type was originallv covered with a forest growth. It is estimated that about 85 per cent, of the type is in cultivation, the remainder being in forest and pasture.

While the type is of lower agricultural value than the soils of the Summit, Pettis, and Crawford series, it can easih- be inn)ro\-ed. It is naturally low in organic matter and is greatly benefited by the plowing under of stable manure or leguminous crops, such as clover, soy beans, and cowpeas, and by applications of ground limestone.

Boone Fine Sandy Loam. - Typically the Boone fine sandy loam is a yellowish-gray to yellowish-brown fine sandy loam, underlain at about 18 inches by a loam stratum, below which the soil usually is a yellowish-brown sandy clay loam, becoming slightly heavier with depth and having a reddish shade in places.

This soil has its most extensive development in a belt about three miles wide extending from Fayetteville to Post Oak. It occurs along the slopes of streams running through the Warrensburg sandstone area.

Most of this soil is in cultivation. It is deficient in organic matter, and less productive than the heavier soils. It is warm and porous, however, and with liberal applications of manure, or with crop rotations including leguminous crops, produces good yields of small fruits and fair yields of corn and wheat.

to 20 per cent, of gravel derived from shales. It is underlaid by a clay loam to clay, generally of a grayish to mottled yellow and gra\' color.

This type occurs principally in the section to the south of Montserrat, occupying steep slopes along the creeks and ravines. It supports a good growth of grass. Little of the type can be culti\ated. on account of its rough topograpliw It is of practically no agricultural importance.

Bates Series. - The soils of the Rates series are dark gray. The series is of residual origin, and is derived from sandstone and shale with interbedded limestones. The soils of this series are distinguished from those of the associated Oswego series by their pervious subsoils and from the Boone series by the darker color of the surface soils. In Johnson county the series is represented by a single type, the Bates silt loam.

Bates Silt Loam. - The Bates silt loam is typically a dark grayish brown to black silt loam, grading at about 15 inches into a brown to grayish-brown silty clay loam mottled with yellow. The subsoil below about 25 inches is a brown to yellow-brown silty clay loam or clay loam, with yellow and red spots in the lower part of the 3-foot section.

The type has its most extensive distribution in the x'icinit}- of Leeton and Chilhowee. Its topography, except along the slopes of creeks, is smooth to rolling. It is one of the most productive in the county when properly managed. The subsoil is such that the type is especially drought resistant, and the material is sufficiently porous to permit an extensive root development. Excepting the Pettis and Crawford silt loams, this type has the best physical structure of any residual soil in the county. Its organic-matter content on many farms is rather low, however, owing to the continuous production of grain crops without adequate provision for the supplying of manure to the land.

Oswego Silt Loam. - The soil of the Oswego silt loam is a darkgray to gravish-brown silt loam, which becomes somewhat lighter in color at a depth of about 10 inches. At about 15 inches a chocolatebrown to drab-colored, heavy silty clay loam is encountered, and at 18 to 27 inches the subsoil is a brownish to dral). imper\ious, heavy clay which becomes mottled yellow, gray, and brown in color. When dry the surface soil is light gray. The soil is very deficient in organic matter and of low moisture-holding capacity.

The Oswego silt loam has an extensive distribution in the extreme southeastern part of the county. The topography varies from flat to gently undulating. Subdrainage is generally deficient, owing to the impervious character of the subsoil, which in places approaches the structure of hardpan, and crops sufi'er from drought. Much of the type is locally called "hardpan land."

Cherokee Silt Loam. - The Cherokee silt loam is light brown to brown in color with gray subsurface material. The subsoil, beginning abruptly at 12 to 20 inches, is a heavy, plastic clay. Below 24 to 30 inches the material is often lighter in both color and texture and more friable in structure.

The Cherokee silt loam is inextensive, occurring in the southeastern part of the county along Muddy creek and other small streams southeast of Knob Noster. The topography is smooth. The soil is poorly drained, owing to its subsoil structure and its topographic position. ]\Iost of it is in pasture. Its agricultural value is rather low.

Osage Series. - The Osage series consist of dark-gray to almost black soils composed of alluvial wash from the sandstone and shale soils of the prairie regions. Three types, the Osage silt loam, silty clay loam, and clay, are recognized in Johnson county.

Osage Silt Loam. - The Osage silt loam is variable in color and texture. Predominantly, it is a dark-gray to brownish-black, mellow silt loam to a depth of about 16 inches, below which the color is lighter gray to grayish drab. At about 20 inches the material is a silty clay loam, which grades below into a drab clay.

Along Blackwater creek, particularly north of W'arrensburg. the soil below 12 inches is much heax'ier than usual, being a hea\'y silt loam. The subsoil of such areas usually is a drab-colored, tenacious clay to clay loam in the lower part of the three-foot section.

The material of the Osage silt loam consists of allu\'ium dcri\-ed from the residual soils of the uplands. In areas of the Crawford and Boone soils the border of the bottom is usually marked by a sharp escarpment, whereas in areas of the Summit soils the rise from the valley to the upland is usually gradual.

This soil is mucli more easil}- maintained in a proiluctive condition than the upland types because of the deposition of material rich in plant food by the occasional overflows. The porous nature of the soil and subsoil favors good drainage and the soil is ready for cultivation soon after overflows. It is a better drained soil than either the Osage silty clay loam or clay.

The agricultural value of this type, as well as that of the other first-bottom soils, has been greatly enhanced in recent vears bv the construction of an extensive system of drainage ditches.

Osage Silty Clay Loam. - The surface soil of the Osage silty clav loam is a dark-gray to almost black silty clav loam, underlain at IS to 20 inches by a drab to black clay loam, which changes into a drab, heavy, plastic clay in the lower part of the three-foot section. Brown and gray mottlings sometimes appear in the lower sulisoil.

The type occurs in close association with the Osage silt loam. It is a first-bottom soil derived from the upland soils of the Summit, Bates. Oswego, Crawford, Pettis, and Boone series. It has its most extensive distribution along Big creek in the southwestern part of the countv, although other important areas are found along Blackwater creek and other streams.

The type is generally best developed near the outer margin of the bottoms. Although its position is lower than that of the silt loam, the difYerence in elevation is not marked by terraces; the slope to the silt loam is almost imperceptible.

The type is subject to overflow from the streams along which it occurs. It is not so well drained as the silt loam, and on account of its hea\-ier texture is not so easily worked. It is greatly benefited by fall plowing and the incorporation of large quantities of organic matter.

Osage Clay. - The Osage clay consists of a black, hea\'y, ])lastic clay or clay loam, grading at about 12 inches into a bluish-black to drabcolored plastic clay, which continues throughout the three-foot section. It has been formed by deposition from overflows and backwater, the currents of which carry only the clay and finer silt particles.

This type is inextensive and occupies depressed areas in the bottoms of Big creek and Blackwater creek, which usually occur away from the channels of the streams at the foot of the upland.

Chariton Silt Loam. - Typically, the Chariton silt loam is a darkgrav to black silt loam, underlain at aliout 12 inches b\- a gra_\-ish-brown silt loam to silty day loam, which grades at a depth of about 18 inches into a dark-grayish or brownish-drab mottled with brown, compact silty clay loam or clay.

The Chariton silt loam is a terrace or second-bottom soil occurring along the various creeks of the county, and occupying former flood plains of the streams. The largest area of the type occurs along Blackwater creek, in the extreme northeastern part of the county. Many smaller areas occur in other sections. The topography is flat. The type has an elevation generally of 15 to 20 feet above the level of the first bottom, and only a small part of it is subject to overflow. In some places, however, the difference in elevation is not over 5 or 6 feet as shown at the margin of the terrace.

This soil is very productive, and more drought resistant than the upland types. AVith proper management, including the frequent working of the surface soil in order to conserve the moisture, this type is easily maintained in a high state of productiveness.

Robertsville Silt Loam. - The soil of the Robertsville silt loam is an ashy-gray silt loam, grading at a depth of aliout IS inches into a grayish-brown, compact silty clay loam. At about 25 inches a brownish, heavy, plastic clay, containing mottlings of gra}' and yellow, is encountered.

This is a terrace or second-bottom soil occurring along the creeks of the county. It usually occupies a lower level than the Chariton soils. Parts of it are subject to occasional overflow. It is derived from wash from the upland soils and, like the associated Chariton series, represents abandoned flood plains.

The topography is flat, except wdiere there are slight undulations that represent old stream or overflow channels. Most of the type is poorly drained, and the establishment of artificial drainage is difticult.

The Summit and Pettis soils, derived from shale and limestone, represent the black prairie soils. They include the best land in the county, are very productive, and are suited to all the staple crops, of which corn, wheat, and grass are the most important.

The Crawford soils comprise the red limestone land, and are characterized by their reddish color and mellow structure. They are naturally productive, and well adapted to wheat, clover, and fruit.

The Oswego and Cherokee soils, derived from shale, are characterized by light-colored surface soils and compact subsoils. They are somewhat inferior agriculturally to the black prairie soils.

The lowland or alluvial soils are composed of alluvium from the uplands. They are grouped in three series, the Osage (first-bottom) soils and the Chariton and Robertsville (second-bottom) soils. The first-bottom soils are generally subject to overflow, but comprise some of the most productive land in the county. They are used largely for corn and grass. The second-bottom soils of the Chariton series are characteristically black as distinguished from the gray second-bottom soils included in the Robertsville series. The black soils are above ordinary high water and are highly productive. The gray soils are mostly above overflow. It requires more careful methods of management to maintain them in a productive state.