Competency Area 3: Soil Testing and Plant Tissue Analysis
Summary
- Soil sampling is the basis for any fertilizer recommendation system. Soil tests give an idea of what nutrients may be available to crops. Field history (such as previous fertilizer applications and tillage) and sampling methods (such as timing, depth, and extraction used) affect the nutrient status and soil test results.
- Soil test interpretations provide guidance as to what types of nutrients to apply and in what forms. The recommendations may vary depending on factors such as environmental risk, extraction method of the test, and estimate of nutrient sufficiency level.
- Plant tissue analyses and the PSNT are tests designed to indicate the current nutrient status of a crop.
- There are critical (ideal) ranges for nutrients for crops. If nutrient levels are below this range, the crop suffers from deficiency. If nutrient levels are much higher than the critical range, the plant may suffer nutrient toxicities, and some nutrients will be taken up in excess.
