ABSTRACT
The previous chapter, on machinery selection, ended with a statement that over many agricultural areas and crops, yields are reduced if planting and/or harvesting are late. We stated that machinery with higher capacity can reduce these losses but will increase the fixed cost of the equipment. Therefore, optimal selection of machinery requires a balancing of these
two types of losses, yield losses and financial loss due to higher fixed costs. The previous chapter introduced a program that makes such an optimal selection, given much detailed data about the cropping system and the available machinery sets. That program runs under DOS and also with the “Command Prompt” of the Windows XP operating system, and it was written in FORTRAN. It runs with assumptions of typical weather for central Illinois and has no other choices. The program described in this chapter, CropPlan, does a similar task, but it has choices about the type of weather data to be used. On the other hand, CropPlan does no optimization, but it does simulate the crop growth and yield as well as the weekly field operations based on weather-influenced good field days and the capacity of the equipment. The data on good field days came from reports of crop observers in Indiana on the weekly number of days when field conditions allowed machinery to be used, and these data were available for each of the four weather scenarios available in the spreadsheet files. It also has changeable economic inputs, so that results are expressed in dollars.
