Tissue testing is a valuable diagnostic tool for helping agronomists ‘listen to plants’. However on its own, test results can lead to misinterpretation of the numbers as they provide a snapshot of what the plant status is at that moment which can be impacted by things like drought, pests, diseases, plant injury, poor soil structure or other causes. The best method of using and interpreting tissue tests is by collecting soil and plant tissue samples from both normal and poor areas, and then comparing results and with published standards for crops of similar stage of development. In addition to consulting with the lab you plan to use for sampling guidelines, these guides may help
- Tissue testing in Corn & Soybeans: Iowa State; https://bit.ly/3eKDxEb
- Rigas Karamanos offers some cautions with interpretation in this Top Crop Manager article: https://bit.ly/3hVxUFo
- Manitoba Soil Fertility Guide includes a table of Crop nutrient sufficiency levels ; https://bit.ly/2TvIxFr
Tissue testing should be combined with a soil test, which can highlight other nutrient issues, compaction, or root issues.