That's the Smell of Money

Posted: May 7, 2013

Wow! The countryside smells rather rank this spring. The air may stink to you, but for a farmer, it's the smell of money.

That money is in the form of fertilizer to feed his or her crops for the growing season. Fertilizer is very expensive, so farmers utilize natural fertilizer options produced on the home farm to feed crops. That natural fertilizer you smell is obviously manure.

Manure provides valuable nutrients for farm crops. Nitrogen, phosphorus and potassium are three nutrients most widely looked at in manures. The amount of each of these nutrients found in manure will vary based on the animal species that produced the manure, as well as how those animals were fed and whether or not any bedding is included in the manure.

Farmers can have the manure tested to determine how much of the nutrients are present in a ton or 1,000 gallons of liquid manure or they can use values determined through research. They also test their soil to find out the nutrient levels already present in the soil.  This allows the farmer to determine how many lbs. of additional nutrients a crop will require for the growing season. Farmers need to keep their soil in optimum health with optimum fertility. This translates into healthy and high quality crops, as well as good yields for the year, provided the weather cooperates.

Here’s how a farmer might determine how much manure to apply to a field. If he or she is planning to plant corn, then he or she needs to determine what yield might be expected. If 150 bushels of corn is the target for each acre planted, then the farmer will want to plan on having 1.1 lbs. of nitrogen available to feed the crop for each bushel produced. That means an acre of corn that produces 150 bushels of shelled corn will need 165 lbs. of nitrogen.

The soil test will make recommendations for how much nitrogen needs added to the soil based on what is already present in the soil and the expected yield. The farmer can then adjust how much manure is applied to the field to meet those nutrient requirements. Additional commercial fertilizer may be needed, because the manure won’t match perfectly with the crop’s nutrient requirements.

Once the manure has been applied, the farmer will account for those nutrients by deducting the amounts of those nutrients applied from the soil test recommendations for each of the nutrients. In this way, the farmer can determine if there is a need to add additional fertilizer to the crops. Accounting for those nutrients not only saves the farmer money, but also protects the environment by not adding more nutrients to the soil than what the plants need.

For more information about manure management for crop production, contact Melanie at the Penn State Extension office in Bedford County at 814.623.4800 or by email at