“Good” Vs. “Bad” In Season Soil Tests

When diagnosing seasonal crop issues a soil test is often a key piece of information. When using a soil test in this manner it is best to collect a sample from the affected area and then another sample from just beyond the boundary of the affected area. If the issue appears to have various levels of severity, a sample from each of these areas is advisable.

Commonly when the cause of the issue is soil fertility related, the unaffected area, or “good” sample, is also being impacted to a lesser extent. Often in season crop issues related to soil fertility are not isolated and often more than one aspect of the soil test is impacting the plants. Without sampling the unaffected area, it may not be possible to isolate which aspect is ultimately leading to the issue at hand.

If the unaffected area has a low soil test value that is not affecting the crop performance that is equal to, or even lower than to the affected area, not having the “good” sample from the unaffected area could lead to a misdiagnosis. Mismanagement of a given soil test parameter is often not isolated to a small portion of a field and needs to be identified as part of the diagnosis process.

When both affected and unaffected paired samples they are often labeled as “Good” and “Bad”, upon review of the soil test data they would be better described as “Bad” and “Worse”. Understanding of how soil fertility is causing or impacting the crop issue can be missed without paired samples. For more help evaluating the impact of soil fertility from paired diagnostic soil samples, reach out to your Regional ALGL Sales Agronomist.