Saving Money on Soil Fertility

 Happy New Year!

With lower crop prices, many producers are looking at cutting costs.  One place they might consider cutting is soil fertility.  Is this a good idea?  There is no way to know without a recent soil test, no more than 2 years old.  If you nutrient levels are high enough, there is no requirement that fertilizer be applied every year.  Make sure that Calcium and magnesium levels are at the proper levels so that pH is correct.  Decisions on phosphorous and potassium should be based on soil test.  Sulfur is much like nitrogen, so if your soil test indicates that you need sulfur, you should not really cut back much.  

Nitrogen on corn is a place to look at cutting back.  The first thing you can do is use nitrification and urease inhibitors as appropriate for your fertilizer material.  They will not save you under really poor conditions, but they can buy you some time.  The next thing you can look at is sidedressing nitrogen.  You can easily reduce your rate by 25% if sidedressing.  Another thing to look at is the maximum return to N (MRTN).  Researchers in the midwest have accumulated a lot of data over the years and are recommending nitrogen be applied based on economic factors (corn rice and nitrogen price) instead of yield goal and removal.  You should at least be looking at the N-rate Calculator to factor cost prices into your decision. 

Variable rate is another factor to look at to cut costs.  I am sold on VR Lime, phosphorous and potassium.  VR nitrogen is a little more tricky, but using some sort of a chlorophyll sensor might be useful.  Pre-sidedress nitrate testing can help you pinpoint how much nitrogen to use as well. 

I know a lot of what I mentioned cost money to implement, but the savings can be substantial.