Both these soils are deficient in lime, and No. 107 is also deficient in phosphoric acid. The rock from which No. 107 is derived has usually been called "talcose slate”, but a full analysis shows that it contains only a small percentage of magnesia. Soils like No. 107 are quite common throughout the "gold regions", which, as is well known, does not rank as the best farming country. The rock from which No. 103 is derived contains the ordinary mica, and is filled with garnets of large size, often as much as 2 inches in diameter. This soil is fairly productive in good seasons, but cannot stand much dry weather, and, being rather light, soon wears out. It is a good representative of the better class of mica slate soils, and does not exhibit the sterility characteristic of some of them, especially those derived from a mica slate of a purple color running through Cleburne, Clay, and Coosa, into Chilton county, and which are almost barren, supporting a growth consisting almost entirely of stunted long-leaf pines and black-jacks.

A comparison of the four analyses given on page 16 shows that the soils may be divided into two general classes, viz, sandy and clayey or loamy. To the first belong the two gray soils, i. e., the gneissic and the hydromica; to the second, the red soils, i. e., the hornblendic and the mica slate; and, in the most general terms, the soils of this region are usually grouped under one or the other of two heads, as sandy or gray, and as loamy or red soils. In some rare instances we have loamy or clayey soils which are deficient in red coloring matter, but as a general thing the clayey and the ferruginous matters are closely associated.

This close agreement of the soils in composition, though derived from rocks of different kinds, bears out what was said concerning the relations between the different rocks themselves; for since the great majority of the rocks of this region may be classed with the gneisses, and as these vary in the one direction, by the accession of hornblende or other iron-bearing minerals, through hornblendic gneisses to almost purely hornblendic slates, so the corresponding soils pass from light-grayish colors through the various grades of yellow to deep red; and since the increase in the amount of hornblende is usually attended with a decrease in the amount of free quartz or silica, it is easily seen that these soils are less and less distinctively sandy as they pass from light to red colors. Variations in the gneisses take place in another direction by the gradual disappearance of the feldspar and the corresponding increase in the proportion of quartz and mica, as when the gneiss passes into mica slate. In this series the light-colored feldspathic soil gradually loses its fertility, becoming more sandy and sterile till the sandy micaceous soils of the typical mica slates are reached. No analyses are yet on hand of the clay slate soils.

THE COOSA VALLEY REGION AND ITS OUTLIERS.

The wide valley, with prevailing calcareous rocks, which lies between the metamorphic area on the one hand and the southeastern edges of the Coosa and Cahaba coal-fields and Lookout mountain on the other has received the name above given from the Coosa river, which traverses its whole length. Geologically it is the continuation of the valley of eastern Tennessee; and, indeed, the valley of which this is a part, and which has been described by Professor Safford as a complex trough fluted with scores of smaller valleys and ridges, extends at least from the Susquehanna river to middle Alabama.

The main valley of the Coosa, with the limits above given, is from 15 to 20 or 30 miles wide, and is closely furrowed with parallel valleys and ridges, all trending northeast and southwest. This valley is embraced in the counties of Cherokee, Cleburne, Calhoun, Etowah, Saint Clair, Talladega, Shelby, Coosa, and Chilton, and has an area, including its ridge lands, of 2,580 square miles. Several outlying valleys, with very similar geological structure and soil varieties, may be most conveniently described in connection with it.

These outliers are: 1. The Cahaba valley, lying between the Coosa and Cahaba coal-fields, in the counties of Saint Clair, Jefferson, Shelby, and Bibb, its area being 385 square miles. 2. Roup's and Jones' valley, between the Cahaba and Warrior coal-fields, in Jefferson, Tuscaloosa, and Bibb counties; area, 285 square miles. 3. Wills' valley, between Lookout and Sand mountains, in De Kalb, Etowah, and Saint Clair counties; area, 460 square miles. 4. Murphree's valley, in Etowah and Blount counties; area, 110 square miles. 5. The Blount springs, or Brown's valley, which is a prolongation into Alabama of the Sequatchie valley of Tennessee, and runs through Jackson, Marshall, and Blount counties, having an area of about 460 square miles.

GEOLOGICAL FORMATIONS.-The strata which appear at the surface and contribute to the formation of the soils in all these valleys are the representatives of all the geological formations occurring in Alabama, from the primordial or lowest division of the Lower Silurian up to the base of the Coal Measures. In the following statement is given, in descending order, the names and geological positions of these strata, so far as their equivalence has been made out: Carboniferous..... 7. Coal Measures of the Warrior, Cahaba, and Coosa fields.

The lithological and other characters of these different formations, so far as they are of importance from an agricultural point of view, will be given in the special description of the soils.

COOSA VALLEY.

Under this name is included that belt of 30 or 40 miles width east and west lying between the metamorphic area on the one hand and the Coal Measures on the other, and extending from the eastern border of the state, in the counties of Cherokee and Calhoun, southwestward for 120 miles.

With reference to these mountainous borders it may be considered as one valley, but in reality it consists of several parallel valleys separated by ridges of greater or less height. The highest of these ridges are found in the southeastern part of the valley, where they attain true mountainous proportions.

Section from Sand mountain, on the northwest, to the metamorphic region on the southeast: showing the geological structure of the Coosa Valley region, Lookout mountain, and an outlying anticlinal valley (Wills').

EXPLANATION.-a. Mountains of the Metamorphic region. b. Sandy mountain lands-Potsdam sandstone. c. Ridgy lands of the Upper Sandstone. d. Red valley lands of the shale and the lower part of the Magnesian limestone. In the Coosa River region and central parts of Wills' valley the shale forms "flatwoods ". e. Loams and cherty gravelly ridge lands, based on the Magnesian limestone. f. Brown loams of the valleys, based on Trenton limestone. g. Red ore ridges. Silurian sandstones and ore on one side and sub-Carboniferous cherty limestones on the other. The cherty gravel covers the side next to the Coal Measures. h. Brown loams of the valleys, based on sub-Carboniferous limestones. i. Sandy lands of Lookout and Sand mountains, Coal Measures. The sandstones, etc., of Coal Measures form the borders of the anticlinal valleys.

The structure of the Coosa Valley region, as well as that of an outlying anticlinal valley, will be easily understood by an examination of the accompanying sketch, which represents a section from Saud mountain, across Wills' valley, Lookout mountain, and Coosa valley, to the mountains of the metamorphic region. The section is taken from northwest to southeast, at right angles to the general direction of the strata, and the sketch does not pretend to give the minute details of structure, but only its broad outlines, and it is therefore in great degree diagrammatic.

The structure of the Coosa valley varies with the locality. From the Georgia line down to Gadsden it consists of two parts, the western being a large anticlinal, and the eastern being formed of strata repeated by faults. The eastern side of the anticlinal is itself cut short by a fault. Below Gadsden the anticlinal turns westward from the river, and is merged into Jones' valley, while the Coosa valley proper is altogether within the area of the faulted series.

The sketch, taken together with the lithological and topographical characters given in connection with the special description of the soils, will show very clearly the part borne by each formation in the production of the topographical features of this valley. It will be noticed that the ridges are of four kinds, viz: in the anticlinal, the red ore ridges, usually steep, with chert fragments on one side and sandstone and limestone on the other; the ridges of the dolomite, rounded and covered with masses of chert. In the eastern part of the Coosa valley the ridges are the chert ridges of the dolomite, the sandstone ridges of the upper sandstone, steep and sharp-crested, but not high, and lastly the mountains of Potsdam sandstone.

The valley-making formations are the sub-Carboniferous in part, the Trenton and Chazy, the calcareous parts of the dolomite, and the shale. The first of these (sub-Carboniferous) is found only in the anticlinal part of the valley; the others are found in both parts. The immediate valley of the river as far south as Gadsden is underlaid by the shales, covered, however, in great measure, with the sands and pebbles of a later period. The dolomite,'as usual, forms the greater part of the superficial area of the ridgy valleys on each side of this central portion, and, from an agricultural point of view, is perhaps the most important formation. (a)

OUTLIERS OF THE COOSA VALLEY.

Cahaba valley.-This valley lies between the Coosa and Cahaba coal-fields. In its geological structure it resembles the eastern part of the Coosa valley, for a fault on its western edge brings the upper sandstone up to the level of the Cahaba Coal Measures, and going thence eastward we pass, in ascending order, over the following strata Upper sandstone, the shale, the dolomite, Chazy and Trenton, Clinton, black shale, sub-Carboniferous, and Coal Measures (Coosa field). As in other cases, the greater part of the area of the valley is made by the strata of the magnesian limestone or dolomite.

Roup's and Jones' valley.-These names are given to the two ends of the valley lying between the Cahaba and the lower part of the Warrior field, merging into the Cahaba and Coosa valleys above Springville.

Wills' valley, Murphree's valley, and Brown's valley.-There are troughs sunk in the Coal Measures of the northeastern or plateau division of the Warrior field. In structure these are all, with the exception of the Cahaba valley above described, anticlinal folds in the Warrior measures, furrowed out subsequently by erosion. While the

a In the sketch the dolomite does not occupy its proper proportion of the area.

floors of these valleys are much lower than the rims which bound them (for the folding involved also the strata of the Coal Measures for a short distance on each side), they are nevertheless considerably higher than the synclinal basins of the Coal Measures, between which they lie, and for that reason water rising in these valleys sooner or later breaks through the mountain rim and flows off into the streams which drain the basins.

Exceptions to this general statement are found in what has been termed the plateau region of northeastern Alabama, and an examination of the map will show that the tributaries of the Tennessee in Marshall and De Kalb counties rise on the plateau near the edge of Wills' valley, flowing down and across the plateau, while the streams rising in the valley flow along it to each end of the same and do not break across the Coal Measures on either side.

The section on page 18 represents in a general way the geological structure of all these valleys, and shows with sufficient distinctness the parts borne by each of the formations appearing in them, determining their topography, the remarks under the Coosa valley applying here also. The structure is, however, especially in the southwestern part of this region, rarely so simple as is represented in the section, for the anticlinal fold has in some cases been thrust or lapped over toward the northwest, thus causing some of the more recent formations to lie beneath the older, and in addition to this, by reason of a fault or break in the strata, the red-ore ridge, on the western side of the valley, has been duplicated. This duplication of the Red mountain is characteristic of the valley from the upper edge of Tuscaloosa county nearly through Jefferson. On the western side of the valley also the strata are usually very nearly vertical, and a very prominent ridge is made by the thick bed of a conglomerate which lies at the base of the Coal Measures. At a short distance from this ridge the strata of the Warrior measures have their usual nearly horizontal position.

The red-ore ridges are commonly of very unequal size on the two sides of the valleys, rising to the dimensions of small mountains on one side, while on the other they are so insignificant in size as to be often overlooked entirely.

SOILS OF THE COOSA AND OUTLYING VALLEYS.-Classified according to color and general physical characters, the soils occurring in these valleys are either red or brown loams derived from the pure calcareous formations, such as parts of the shale, the dolomite, Trenton, and sub-Carboniferous; or lighter colored to gray siliceous soils, usually filled with angular, flinty gravel, and resting on a yellowish clayey subsoil derived from cherty limestones of the dolomite and of the sub-Carboniferous; or the light sandy loams which result from the disintegration of sandstones such as make up the greater part of the Potsdam proper, the upper sandstone, and the Coal Measures. But since the soils of each of these classes vary according to the geological formation to which they owe their origin their discussion in connection with these formations will best bring out their peculiarities of composition and explain their distribution in the valleys.

Acadian slates and conglomerates.-These have received notice under the preceding division, since they are more or less metamorphosed and crystalline in texture, and are otherwise closely associated with the true metamorphic rocks.

Potsdam sandstone. The principal rock of this group has already been mentioned as a rather coarse-grained sandstone, and hence the resulting soil is sandy. In many places the soil is thin and vegetation scanty and stunted, but occasionally the growth is vigorous, consisting of the upland oaks, chestnut, and short-leaf pine. By reason of the mountainous character of the country made by these rocks very little of this soil is under cultivation, but there are many spots of good grazing ground. The Potsdam sandstone, in a series of outlying mountains, forming an interrupted chain, skirts the western border of the metamorphic region and extends through the counties of Cherokee, Calhoun, and Talladega.

Upper sandstone. -The soils derived from this formation are usually somewhat calcareous, though sandy, but the sharp-crested, steep ridges to which they are confined are seldom under cultivation. The entire thickness of the formation is inconsiderable, and as the strata usually lie tilted at high angles the superficial area occupied by them is quite limited. Isolated ridges of these rocks are found in the Coosa valley, in the counties of Cherokee, Calhoun, and Talladega, and in the Cahaba valley in Shelby and Saint Clair counties. Besides these occurrences, the mountains of Potsdam sandstone above described have usually a narrow border of these rocks on their eastern slopes.

The shale. This formation in its outcrops presents two well-marked phases. Its lower beds are mostly shales, which, at the surface, have been thoroughly leached of calcareous matter, and generally break up into small fragments having very much the appearance of shoe-pegs. The colors of these shales are chocolate-brown, red, greenish, and gray. The soils formed from these materials are usually thin, and, though considered productive in good seasons, are liable to injury from drought. The timber is a mixture of chestnut, red, and white oaks, dogwood, and hickory. The valleys occupied by these variegated shales are ridgy, the shale ridges being often almost bare of soil. Areas of these shales are usually associated with the outcrops of the upper sandstone, with the upper strata of which they are closely related lithologically, and characteristic occurrences are not infrequent in Bibb county, northeast of Centerville, near Pratt's Ferry, in the vicinity of Montevallo, and Helena, in Shelby, and along the southeastern flanks of the isolated ridges of the upper sandstone and the mountains of Potsdam sandstone in Talladega, Calhoun, and Cherokee counties.

On the other hand, the upper strata of the formation are frequently thin sheets of limestone, alternating with seams of clay and with thin beds of sandy and aluminous shales. These beds often occupy the central parts of the anticlinal valleys as a mass of greatly contorted, usually nearly vertical strata, of which the thin-bedded limestone forms the greater part, the shales and clay being mostly weathered out, giving rise to a stiff clayey soil, through which the edges of the limestone protrude.

Flatwoods. Where the clayey portions predominate and the drainage is defective level tracts are formed, which are known as "flatwoods", and which are usually uncultivated, though the timber indicates a soil by no means. sterile. The prevailing timber of the flatwoods is post oak and short-leaf pine. The soils are usually of a greenishyellow color, sometimes red in places, and occasionally nearly black. Where roads cross the flatwoods they are easily cut up into deep, muddy ruts, in which water stands for a long time. Occasionally a high place may be encountered with sandy soil and under cultivation, but these spots form a very small proportion of the whole area of the flatwoods.

Some of the largest bodies of flatwoods are found in the anticlinal part of the Coosa valley below Gaylesville, in Cherokee county, extending down to Gadsden (well exposed below Cornwall, at Cedar Bluff, and below Round mountain), and thence below Gadsden, in the direction of Springville, nearly to the latter place; also in Jones' valley between Elyton and Jonesboro', and in small patches farther south in Jones' and Roup's valley.

In the immediate valley of the Coosa river the shales have usually a superficial covering of sand and pebbles. belonging to a much more recent formation, but along the river bluffs they may be seen underneath the surface beds. Throughout these flatwoods the outcroppings of the limestone are frequent, and in places there is very little soil, the rocky surface being then usually occupied by cedar glades. Similar glades are also often formed by the shaly limestones of the Trenton period.

From the flatwoods between Springville and Gadsden a specimen of soil was collected which may be considered as a representative. The analysis is as follows:

No. 70. Flatwoods soil (the Lower Silurian shale) from 3 miles northeast of Asheville, Saint Clair county. Depth, 10 inches; vegetation, chiefly post oaks and short-leaf pine, with red, Spanish, and a few black-jack oaks. Color,. gray on top, changing within 3 inches to buff-yellow.

The analysis shows that this is not such an inferior soil as its total neglect by the farmers would indicate,. although the phosphates and vegetable matter are low. The natural growth, also, which is of fine, sturdy trees, tells in its favor. Many soils are successfully tilled which have no better chemical composition than this. Physically, however, it is too heavy and cold for cultivation, except where mixed with sand, as is the case near the banks of some of the streams which traverse it. Almost the only inhabitants of the flatwoods are to be found along these water-courses. During the winter and spring, by reason of mud and holes, the roads are almost impassable. In its uppermost portions this formation exhibits very similar strata to the lowest beds of the next succeeding, there being no well-defined line of demarkation between them.

The great body of deep, red-colored, clayey loams occurring in the Coosa Valley region, and especially in its eastern part, may be assigned, as to their origin, either to the lowermost of the beds of the shale or to the uppermost of the dolomite. They will be more particularly described under the next head, though in part, without doubt,. belonging here.

The magnesian limestone, or dolomite.-This in Alabama has the widest distribution of any of the calcareous formations, and for this reason, and because it underlies a large proportion of the cultivated valleys in this part of the state, its importance from an agricultural standpoint is very great. It has been stated that the lower beds of the dolomite are more calcareous, the upper, as a rule, siliceous or cherty, and the resulting soils in their extremes are of two kinds:

1. A clayey loam of light-yellowish to orange-red colors and of varying thickness, the average being perhaps one and a half feet. The subsoil is usually heavier, being a rather stiff clay or clay loam of a red or yellow color. Both soil and subsoil are often filled with lumps of limonite or brown iron ore. Beneath the subsoil, at varying depths, lies the dolomite or limestone. There is a great variety in the color of the top soil between a very light-yellow, almost gray, and a deep red and brown, but the subsoil is commonly a yellow or red clay, and it is not unusual to find these soils and subsoils, especially those of lighter colors, filled with angular fragments of chert.

The characteristic timber upon the red lands is red, Spanish, post, and black-jack oaks, hickory, short-leaf pine, and dogwood; in low grounds, sweet gum and sour gum in addition to the above.

Some of the best farming lands in the state are based upon these lower beds of the dolomite and upon the immediately underlying calcareous parts of the shale, and their widest distribution is to be seen in the eastern part of the Coosa valley, in Cherokee, Calhoun, and Talladega counties, and southward, in the same direction, in Shelby and Bibb counties. The greater part of the red and brown loams with deep red-colored subsoils occurring along the eastern border of this long series of valleys is derived from the dolomite, but red and brown loams of a somewhat similar nature are also derived both from the shale below and from the Trenton rocks above the dolomite. In the anticlinal valleys these lower beds of the dolomite do not form the surface to so great an extent, and the deep red soils are of less frequent occurrence than in the Coosa valley.

2. The upper siliceous beds of the dolomite, in disintegrating, yield as a rule gray soils, which are filled with angular chert fragments. The subsoils are mostly of a yellowish to red color and of clayey substance, though the clayey substratum may sometimes lie at considerable depths below the surface. The agricultural characters of the lands made by these upper beds vary between wide limits, from good brown loams on the one hand to gray siliceous and nearly barren soils on the other.

The cherty portions of the dolomite, from the weathering away of the calcareous part, gradually accumulate and protect the strata from further erosion, and in this way the chert ridges so characteristic of the formation originate. The chert, which is of concretionary nature (and not bedded), occurs sometimes in masses of great size, and the surface of the hills is so covered as to leave very little soil exposed, and that of a highly siliceous character. In such cases the growth is chiefly of long-leaf pine and black-jack oak. The broad chert ridges of the Coosa valley in Cherokee, Calhoun, Talladega, and Shelby counties are very commonly timbered with the long-leaf pine.

Occasionally the country formed by this part of the dolomite is rolling or slightly broken, rather than hilly, varied with lime-sinks and outcrops of the cherty dolomite. The southwestern part of Talladega county, near the Coosa river, furnishes a good example of these rolling piny woods, which in many respects remind one of the rolling piny woods of the southern counties. Such soils have little to recommend them, and we find the country almost uninhabited, except along the banks of the streams which drain it, and these are few in number. Where the chert is less prominent as a surface material the gray lands are frequently of very fair quality, and, while not so fertile as some of the red lands, are thought to be better adapted to the cotton crop, especially where commercial fertilizers are used.

The better grades of the gray, gravelly lands are timbered with oaks and short-leaf pine, hickory, dogwood, etc., while those of a sandier nature have the long-leaf pine, associated with post, Spanish, and black-jack oaks and small hickories. The gray pine lands near the Alabama furnace, in Talladega county, may be taken as types of this last-named variety.

In the outlying valleys there is always at least one of these chert ridges occupying the center of the valley, but it is more commonly separated into two by a narrow valley resting on the more calcareous lower parts of the dolomite, or by a belt of flatwoods derived from the underlying shales. These ridges are timbered usually with post, black-jack, and Spanish oaks, with some chestnut and short-leaf pine. The long-leaf pine is also found where the siliceous matter preponderates. Occasionally the cherty matter assumes the form of a sandstone or conglomerate, which forms considerable hills. This is best seen in the Salem hills, near Jonesboro', in Jones' valley, and again a few miles southwest of Springville, in Saint Clair county. The Salem hills have a characteristic growth of long-leaf pine, as yet untouched by the woodman's ax.

The chemical composition of typical soils derived from the rock varieties occurring in the dolomite are fairly exhibited in the analyses of four red-loam soils and one gray, cherty soil taken from several localities. Only the better soils, such as are under cultivation, have been examined. The barren soils of the chert hills and pine woods are not often in cultivation, and have not, therefore, been selected for analysis. In Calhoun, Talladega, Shelby, and Bibb counties the red soils appear most prominently.

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