| Written April, 2002 |  |
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File A3-28 |
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Estimating the Number of Field Days Required
| Use this decision tool to estimate the number of field days required to complete a field operation. |
The following worksheet can be used to estimate the number of field days required for tillage, planting, and harvesting for a particular farming operation.
Column 1. List all the field operations to be done before planting. Include fall and spring tillage, application of chemicals, and sowing of small grain or forages. Do not include custom hired operations.
Column 2. List the total acres to be covered by each operation. Remember, if some acres have the same operation performed on them more than once, multiply the number of acres by the times over.
Column 3. List the sizes of the machines used for all operations.
Column 4. List the field capacity of each machine in acres per hour. Suggestions can be found in Information File Estimating Field Capacity of Farm Machines, or by using the suggested values for speed and field efficiency from Table 1 in the following formula:
field capacity (A/hr)=
speed (mph) x field efficiency (%) x width (ft) /825
It may be more convenient to skip directly to column 6 and enter the number of acres covered per day, if this is known.
Column 5. Enter the number of labor hours available per day in the field to perform each tillage and preplant operation. Do not count time spent on repairs, transportation of machinery, livestock activities, etc. For planting and harvesting, enter the number of hours per day the planter or combine can be used.
Column 6. Multiply column 4 by column 5 to estimate the number of acres covered per day for each operation. Decide if this is a reasonable figure based on experience.
Column 7. Estimate the number of field days needed for each operation by dividing column 2 by column 6. Then find the total for each group of field operations.
Use extra lines to estimate how the number of field days required can be adjusted. Adjustements can be made by changing machinery size, number of field operations, number of acres covered, proportion of acres in each crop, hours available for fieldwork, or by custom hiring some operations.
This worksheet can also be used to estimate the number of field days required for harvesting forages. This can be compared to the expected number of field days available in the appropriate period, as shown in Information File Fieldwork Days in Iowa.
Worksheets are presented in the accompanying "pdf" file that you can access by clicking here or on the icon above.