Agriculture Reference
In-Depth Information
Table 3.3 (continued)
A Modern Description of the Craig Series
LOCATION CRAIG OK + MO
The E horizon
is dark gray (10YR 4/1), dark grayish brown (10YR 4/2), brown (10YR 4/3, 5/3), gray (10YR
5/1), or grayish brown (10YR 5/2). Texture and coarse fragments are similar to those in the A horizon.
The BE horizon
is very dark grayish brown (10YR 3/2), dark brown (10YR 3/3; 7.5YR 3/2), dark yellowish
brown (10YR 3/4, 4/4), dark grayish brown (10YR 4/2), brown (10YR 4/3, 5/3; 7.5YR 4/2, 4/4, 5/2, 5/4),
grayish brown (10YR 5/2), or yellowish brown (10YR 5/4). It is loam, silt loam, clay loam, silty clay loam,
cherty loam, cherty silt loam, cherty clay loam, or cherty silty clay loam. Coarse fragments more than 3 in.
in diameter range from 0 to 5% of the volume and coarse fragments less than 3 in. diameter make up 1 to
50% of the volume.
The Bt horizon
is brown (10YR 4/3, 5/3; 7.5YR 4/4, 5/4), dark yellowish brown (10YR 4/4), yellowish brown
(10YR 5/4, 5/6), strong brown (7.5YR 5/6), reddish brown (5YR 4/3, 4/4, 5/3, 5/4), or yellowish red (5YR
4/6, 5/6). The lower Bt horizon also includes yellowish brown (10YR 5/8), pale brown (10YR 6/3); light
yellowish brown (10YR 6/4), brownish yellow (10YR 6/6, 6/8), strong brown (7.5YR 5/8), light brown (7.5YR
6/4), reddish yellow (7.5YR 6/6, 6/8), or yellowish red (5YR 4/8, 5/8). The Bt horizon is cherty silty clay
loam, cherty clay, cherty silty clay, very cherty silty clay loam, very cherty clay loam, very cherty clay, or
very cherty silty clay. The upper 20 in. clay percentage ranges from 35 to 45. Coarse fragments more than
3 in. in diameter range from 5 to 10% of the volume and coarse fragments less than 3 in. in diameter range
from 35 to 90% of the volume.
The BC horizon
is strong brown (7.5YR 5/6, 5/8), reddish yellow (7.5YR 6/6, 6/8; 5YR 6/6, 6/8), yellowish
red (5YR 4/6, 4/8, 5/6, 5/8), red (2.5YR 4/6, 4/8, 5/6, 5/8), or light red (2.5YR 6/6, 6/8). It is very cherty
clay loam or very cherty clay. Coarse fragments more than 3 in. diameter range from 5 to 10% of the volume
and coarse fragments less than 3 in. diameter range from 65 to 90% of the volume.
An R laye
r of cherty limestone occurs at depths ranging from 5 ft to 30 ft below the surface.
COMPETING SERIES:
These are the Boxville, Braxton, Eldon, Eldorado, and Riverton series. Boxville and
Braxton soils have clayey control sections. Eldon soils have mesic temperatures. Eldorado and Riverton
soils have loamy-skeletal control sections.
GEOGRAPHIC SETTING:
The Craig soils are on uplands. Slope gradients range from 0 to 5%, mainly less
than 3%. The Craig soils are formed in residuum weathered from cherty limestones. The average annual
precipitation ranges from about 37 to 47 in., the annual Thornthwaite P-E indices from 64 to about 80, and
the average annual air temperature ranges from 57° to about 62° F.
GEOGRAPHICALLY ASSOCIATED SOILS:
These are the competing Eldorado series, and the Bates,
Dennis, and Parsons series. Bates, Dennis, and Parsons soils contain little or no chert.
DRAINAGE AND PERMEABILITY:
Well drained; medium runoff; moderately slow permeability.
USE AND VEGETATION:
Some areas cultivated to small grains and sorghums. Some areas are in native
range of tall prairie grasses or in improved pasture. The native vegetation is tall grass prairie.
DISTRIBUTION AND EXTENT:
Northeastern Oklahoma and possibly in southwestern Missouri, northwestern
Arkansas, and southeastern Kansas. The series is minor in extent.
MLRA OFFICE RESPONSIBLE:
Salina, Kansas.
SERIES ESTABLISHED:
Craig County, Oklahoma; 1931.
During the same period, there were intensive activities under way in Europe to develop national
systems. A most notable contribution was that of the French pedologists who had begun to develop
their system in the early Ýfties, and published it in 1967 (CPCS, 1967). The U.S. System saw its
debut in 1960 as the 7
Approximation, which was the Ýrst operational version of Soil Taxonomy.
In the meantime, there were other groups developing concepts and terminology for speciÝc uses.
Two outstanding contributions include the Soil Map of the World Project, for which a legend was
developed by the Food and Agricultural Organization of the United Nations (FAO, 1971Ï1981).
Another group published the Soil Map of Africa (DÔhoore, 1964). Later, the Ýrst effort toward a
Soil Map of Europe was initiated (Dudal et al., 1970). Although legends were developed for these
small-scale maps, the process also helped to develop units at the higher levels of classiÝcation. The
maps then became a technique for validating the higher levels.
Similar discussions occurred in Europe. FAO organized several working meetings to develop
the legend for the world map. Field trips during such meetings were critical in testing concepts
and developing criteria. Commission V of the International Society of Soil Science (ISSS) also
played an important role in this process through conferences and symposia. Each national, regional,
or international group had an opportunity to report on its progress and obtain critical evaluation of
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