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As your trusted adviser, we're here to answer your questions about how you can maximize yield and increase profitability on your farm. If you have a question or issue, we want to hear from you. Our expert team is standing by and ready to go the extra mile to help.
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Recently Asked Questions

Should I take soil samples based on grids or zones? If so, how often should I take my soil samples?

In general, grid soil sampling is the preferred method of sampling because grids produce a higher resolution. Whereas, zone soil sampling can miss areas of the field that are deficient or proficient in in fertilizer. This affects the amount of fertilizer and where it is placed. That is why it’s important to consult an agronomist to make sure the soil sampling method fits your specific needs.  When there is little to no soil data for your field, grid soil sampling is the best way to capture as much information as possible. Zones can be established based on at least three years of spatial yield data per crop or soil characteristics such as texture and type. These characteristics correlate to yield variability. It’s important to have enough samples in each zone to capture nutrient variability.  A hybrid sampling approach, where each zone is a grid with evenly distributed sample points, is preferred over composite zone sampling, where one composite sample is made to represent that entire zone.

The industry standard for soil sampling frequency is to take soil samples once every three years.  This standard was established based on three year crop rotations. However, today we are seeing fields that grow the same crop for multiple years.  In these cases, some farmers choose to sample every two years.  For farmers who closely monitor their fertility programs due to nutrient variability or potential nutrient losses, sampling every year has proven to be beneficial. Ultimately, every field is different, but soil sampling should occur at least once every three years. 

Can I fertilize based strictly on crop removal?

Yes, you can fertilize based just on crop removal. However, this should only be performed when soil tests show that nutrient levels are sufficient. It is always important to consider the amount of nutrients the previous crops removed from the soil.  According to the International Plant Nutrition Institute, 180 bushels of corn removes 240 lbs of nitrogen, 102 lbs of phosphorus, and 240 lbs of potassium from the soil. A simple way of assessing nutrient levels is to equate it to balancing a checking account. If you want to keep $500 in your account, you need to deposit money to offset your withdrawals.  The same concept applies to nutrient balances in the soil. Fertilizer applications need to be made to offset the nutrients that the previous crop removed. If soil tests show that there aren’t optimal levels of nutrients, additional fertilizer amounts will be needed for the next crop year to meet your expected yield.