Soil samples from the 0-10-cm and 10-20-cm depths were obtained from nine of the 11 soli associations of Arkansas. Sites sampled had a heavy forest cover and showed no evidence of cultivation. Routine soil tests showed that pH values ranged from a low of 4.38 for the Loessial Hills to 5.83 in the Ozark Highlands. Potassium ranged from 69 to 206 kg/ha. Phosphorus was very low in nearly all sites; the extremes were 9 and 83 kg/ha, but most values were less than 30 kg/ha. Calcium ranged from 122 to 1,523 kg/ha. The data indicate that when woodland areas are cleared for cultivation in these nine soil association areas, the soil fertility level will be low.
Tennille, A. W.
"Extractable Nutrients and pH Values from Nine Soil Associations of Arkansas,"
Journal of the Arkansas Academy of Science: Vol. 27
, Article 17.
Available at: http://scholarworks.uark.edu/jaas/vol27/iss1/17