The land base requirement is an estimate of the number of acres needed to fully utilize the nutrients produced in manure over the crop rotation. Most manure, if applied according to crop needs for nitrogen (N), will oversupply crop needs for phosphorus (P2O5). By using the worksheet and tables below, you will be able to estimate the number of acres you need to fully utilize the phosphorus in manure when applied to alfalfa crops.
NOTE: Land base requirements are based on crop yield and can be refined by accounting for nutrient transformations such as mineralization, or for composting or offsite transport. The worksheet below is based on manure production estimates for various livestock types and mineralization rates for phosphorus with no composting or offsite transport. Use the information in the worksheet table for general planning purposes. For further information on how composting or offsite transport may influence land base requirements contact NRCS or Utah State University Extension.
You will need the following information:
Alfalfa yield (in tons / acre) of your land:
Obtain this through your records, or by contacting your local Cooperative Extension agent or NRCS office. Use the average yields obtained, not top yield.
Type and numbers of animals in your operation
Use the following worksheet to estimate the land base requirement for manure produced.
(*Note- Excel spreadsheets are programed to do calculations for you. On some computers you can do calculations directly on your computer. On others you must save Excel files to your computer or disk before using the spreadsheets. )
Directions for Land Base Estimate Worksheet:
1. In Column 1, enter your livestock types (i.e. beef cow, swine, etc).
2. In Column 2, enter the number of animals you own for each type..
3. In Column 6 enter the number obtained from the table at the top of the worksheet file for each livestock type.
4. The worksheet will automatically calculate the total number of acres needed.