BUILDING PASTURE NUTRIENT NEEDS ON YOUR FARM

Whether it is crop production such as corn and beans or livestock production everyone knows if you don’t feed it a well-balanced diet it will not yield, produce, nor gain. This being said most farm pastures, which are crops, are usually being neglected. Some more than others. Not to say all producers are neglecting there forage needs but the question still remains. “Are they doing their best to maintain soil fertility while maximizing potential for outputs and/or profitability?”  After all the more grass produced the more cattle you can run on the same number of acres over a longer period of time. 

Fertilizer is not cheap!!!!  I get it…  But neither is feed.  Building your soil for future production is of greater value over the long hall than many think.  If you are soil testing, you are at least thinking about this. Even if you are only renting a neighbor’s farm, fertility will help you in the future. By the way, if you are fertilizing for plant growth don’t forget that weeds are plants too and they use the high dollar fertility as well. Do not loose valuable fertility to weeds…eliminate them...

No two farms are alike when it comes to soil type and its ability to produce, so what do you really know about your soil conditions and what do you look for in a test? 

When I look at a soil test I look at the following items.Thinking first about production and second about build-up and/ or back…  Just what is in there right now.

 
  • Soil pH -   This controls the flow of nutrients which are available in the soil to the plant. Soil fertility is soil chemistry. Don’t panic, this is not rocket science. If the valve is only half open then it is restricting the ability of flow and plants don’t feed as well as they could thus lowering production and/or probability. By meeting the needs of the plants pH range, opening the flow valve if you please, you will get the best bang for the bucks on the nutrient flow currently available in your soil. Remember it take time for the lime to get into the soil so liming at least 3-6 months before you are wanting to see results is a must..  If fertilizer finances are limited lime first.  Do not skip this as it will affect how the rest of the fertilizer’s work when you apply it as well.  Lime is the gatekeeper. Calculate your needs based on the suggested limestone rate in ENM’s.  If you are around a half a ton or less per acre it may not be cost effective but extra lime will not go to waste I promise you. You usually take soil tests every 3 to 4 years and apply lime only once in that time period so a little extra will not hurt.
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  • Phosphorus (P) Although different crops require different amounts of fertility based on plant type and yield goals I am looking for a balanced soil.  One ready to go to work as you apply and build fertility for the future.  This seems to be the mineral most often short in most of the soil test I review. It will limit production even though you pour on the nitrogen… And by the way the more nitrogen you put on the soil the lower your pH will go over time. I am looking for the P number to be around 40Lbs./A. This may seem like over kill but better to have a little extra available than not enough on those lean years when fertilizer dollars are limited. If broomsedge seems like it is increasing in your hay fields look here. If you continue to mow, rake, and bale hay as well as remove it from your fields without fertility you are depleting/mining your minerals at an alarming rate. 
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  • Potassium (K) This, like phosphorus, will limit production if a shortage occurs in the soil as well. Again different crops require different amounts of fertility based on plant type and yield goals. Here, I am looking for a K number around 200-225 Lbs/A. Remember not all plants are alike and these are guidelines for you to look for so you can get a feel for where you are at and how you would like to proceed.
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  • Magnesium (Mg) Even though magnesium is considered a secondary nutrient it is still important you meet all nutrient needs for the crop.  Keeping this in the medium range on your soil test is a bonus.  There are different ways to apply secondary and micro-nutrients but one of the most common ones used for magnesium is dolomitic limestone, it just comes with the lime from the quarry. 

 

When using the MU Extension soil testing service you will receive our recommendation for your cropping system, not only for this year, but for the next 8 years. Yes, this is an 8 year build-up program based on your requested yield goals. This level of fertility needs to be applied every year (Excluding Liming) until you retest and get a new recommendation based on your progress.  Our goal is to balance your soil for future use as well as the meet the production yield goals you have now as well as in the future.  Remember, if you refuse to feed it right do not expect it to grow at an acceptable rate that will meet your needs in the future.

Another factor soon to play a major part in soil fertility is soil quality.  Research in soil compaction, absorption, permeability, and nutrient flow are all being looked at.  These too have an overall effect as to how the nutrients flow in your soil. Remember the true definition of soil is “A living, naturally occurring dynamic system at the interface of air and rock. I

t forms in response to forces of climate and living organisms that act on parent materials in a specific landscape over a period of time.” We are the keepers of the land. We are responsible for the future generation. 

Just how are we going to leave it for them?

Source: Terry Halleran,  MU Extension Agronomy Specialist