One agronomist in central Indiana has already twisted two $40 hand soil probes and broke a third trying to pull soil samples in a research plot. The company this person works for hasn't pulled out the automatic probe yet, and likely won't unless it rains a significant amount.
The last time this situation existed, a couple of years ago, technicians did significant damage to the power probe trying to test hard soil, the agronomist says. Bending a $40 hand probe is one thing. Tearing up a $6,000 power-driven probe is quite another issue indeed.
So what if you or the people who hire, either consultants that you pay for the service or agronomists that work for the dealership where you buy fertilizer can't probe your fields this fall? If you're in a solid soil-testing program, most fields are set up on a rotation where they are sampled every three or four years, so you should have some fairly recent results as a guide.
One agronomist says they're ready to sit down and work with each producer field-by-field to determine a sound fertilizer recommendation for next year based on the soils test information they have from previous years. They may also factor in crop removal. That could be extremely variable in some fields because yields ranged from zero to 140 based on soil type. In those cases they might recommend variable-rate applications to get more nutrients to those spots where the crop actually used nutrients out of the soil this past year.
The other reason for not forcing soil sampling this fall in very dry, hard soils is that the readings you get back from the lab may not be accurate compared to previous sampling on the field. Potassium levels may be affected the most. Many believe you'll be better off waiting until conditions are appropriate to get back into your normal soil testing routine.