'N DINAMIESE LINE'eRE PROGRAMMERINGSBEPLANNINGSMODEL VIR GEMENGDE VEE-WEIDING-GRAANBOERDERYE

The dinamic linear programming technique can be used as an aid in whole-farm planning. The limited capacity of microcomputers has restricted the development of user-friendly optimizing models and as a result this handy planning method was not commonly used in the South African agricultural sector. The computer revolution has now made it possible to develop a DLP model for microcomputers. The planning horizon of the Optima model on microcomputer is six years and is most suitable for the comprehensive planning of livestock-pasture-grain farms. Assumptions, activities and constraints of such an optimizing model are discussed and the results of different scenarios analysed. The results show that the realistic scenario differs more from the pessimistic scenario and less from the optimistic scenario. The conclusion is that exceptional management is needed during times of lower product prices and yields. During favourable conditions more wheat is planted. This probably indicates wheat to be one of the most profitable crops, but that it is very risky during times of climatic instability