Certified Crop Advisor Practice Exam

Which of the following organic materials would be expected to mineralize the most nitrogen?

1. Composted Leaves

2. Corn Stover

3. Dairy Manure

4. Green Manure

The correct answer is: Dairy Manure

Dairy manure is expected to mineralize the most nitrogen among the options provided due to its high nutrient content and the presence of readily available organic matter. When dairy manure is applied to the soil, its rich nitrogen profile aids in quick decomposition and mineralization, releasing nitrogen in a form that plants can readily absorb. The nitrogen content in dairy manure is typically greater than that found in composted leaves, corn stover, or green manure. This results from the manure's combination of organic compounds, including urea, which efficiently contributes to nitrogen cycling in the soil. Additionally, the microbial activity that occurs when dairy manure is added to the soil is robust, further facilitating the conversion of organic nitrogen into inorganic forms through mineralization. While the other options also contain nitrogen and can contribute to soil fertility, their nitrogen mineralization rates are generally lower than that of dairy manure due to factors such as lower nitrogen concentration or a slower decomposition rate.