28 THE CLAYS OF ARKANSAS. 
BUCKSHOT CLAYS. 
Character. — In many places in this State and at some places over 
a great many square miles, both in the Paleozoic highlands of the 
western part of the State and in the Tertiary and Quaternary low- 
lands of the east, there is a kind of clay, usually of an ashen color, 
but often mottled red, gray, and yellow, that contains great quanti- 
ties of nodules of iron (limonite) varying in size from that of a pin 
head to that of a walnut. This is one of the soils known as " buck- 
shot" land, a name doubtless given to it on account of 'the size and 
form of these nodules. 05 The nodules at some places lie along a 
broad but well-defined line at a uniform depth from the surface; in 
others their depth varies greatly; they may be on the surface or may 
lie as deep as 5 or 6 feet below. 
Origin of the "buckshot." — The process by which these nodules are 
formed seems to be as follows: The iron was originally distributed 
through the uppermost bed of the surface clay. Vegetation growing 
and decaying on the surface furnished vegetable acids to waters that 
penetrated the soil and dissolved out the iron from the upper por- 
tions of the beds. As the iron-charged waters penetrated the clays 
the iron was precipitated at points a short distance below the surface 
to form the buckshot nodules. These nodules are never very abun- 
dant on hillsides or steep slopes/ but occur for the most part on gentle 
slopes and in the soils of the " slashes" or flat lands on which the 
water stands or has stood during wet seasons. The leaching of the 
iron from the upper beds of clay leaves them usually of a pale ashen 
or cream color, while the admixture of organic matter sometimes 
gives them a leaden color. 
Carbonic acid is probably one of the most active agents in dissolv- 
ing the iron from the surface soil and redepositing it at lower depths. 
But on descending with water through the upper layers, so long as 
water stands upon the ground, carbonic acid will not give up its iron. 
If it should pass downward the iron would remain in solution, and if 
it flowed away laterally the iron would be precipitated only when 
the water came near the surface. It therefore seems probable that 
this iron remains in solution until the wet grounds become dry, when 
it is precipitated by the evaporation of the water. As might be 
expected from the conditions under which these lumps of iron are 
formed, they vary in size and in their distance from the surface, and 
the bands in which they are arranged vary in thickness. 
a In Arkansas another kind of soil is also known as buckshot land. The latter is calcareous alluvial 
soil containing considerable clay. After being plowed the clods, on weathering, break into small 
cuboidal lumps, which appear to have suggested the name buckshot by their size rather than by their 
shape. This soil is usually very fertile, while that containing the limonite nodules is rather poor. 
& At Forrest City a band of limonite nodules is exposed in a railway cut 43 feet below the surface. 
This probably represents the ancient soil cited by Chamberlin and Salisbury as underlying the loess. 
(See Call's report on The geology of Crowleys Ridge: Ann. Rept. Geol. Survey Arkansas for 1889, vol. 2, 
p. 159, and PI. I, fig. 2, p. 206.) 
