Heavy fertilizer amounts recently applied may still leave a residue or soluble salts in the soil. Adding further high rates of nitrogen or potash may exceed the amount tolerated by most crops. Certain clay soils and highly fertile garden soils high in organic matter may have high soil test values for phosphorus and potassium but contain only normal amounts of free salts. This is a highly desirable condition. Crops grown under high salt conditions tend to have a dark bluegreen color in addition to stunted growth.
Crops stunted by low fertility are often yellowish.
The salts status of the soil sample is determined from the exchangeable calcium and EC determination for each sample. The salt level classification is indicated in the soil test results. The Arkansas Cooperative Extension Service offers its programs to all eligible persons regardless of race, color, national origin, religion, gender, age, disability, marital or veteran status, or any other legally protected status, and is an Equal Opportunity Employer.