ECONOMIC COMPARISON OF METHODS OF CULTIVATING AND PLANTING CEREALS, SUGAR-BEET AND POTATOES AND THEIR INTERACTION WITH HARVESTING, TIMELINESS AND AVAILABLE LABOR BY LINEAR-PROGRAMMING

The farm gross margins resulting from different cultivation techniques with arable crop rotations of all-cereals or cereals and root crops are compared using a linear programming model. This determines the labour, machinery, crops and optimum times for harvesting, cultivating and planting which give the best farm gross margin for a given set of conditions. The gross margins achieved with other machinery are then compared with this optimum. The model shows the following (see the table below). Direct drilling gives the best gross margin whenever available labour restricts winter cultivations such as on an all-cereal heavy land farm. Irrespective of the primary cultivation system used, secondary cultivation by a linked spring tine/drill instead of a multi-pass harrow and drill produces a £15/ha greater gross margin on all-cereal heavy land. The difference is reduced by mixed cropping and on all cereal light land the difference is £6/ha. The linked system enables all winter wheat to be grown in all cases. Rotary digging and shallow ploughing are the primary cultivations which give the highest farm gross margins. Deep ploughing gives the lowest farm gross margin. Farm gross margins for some cultivation methods with four cropping systems, £/ha. {A table is presented}. © 1978.