Design and performance characteristics of an experimental crop conditioning system for difficult climates

Abstract

Study of established grass mowing and conditioning machines has enabled functional short-comings to be identified and objective crop treatment criteria to be formulated. Subsequent development has led to an experimental crop conditioning system which takes account of the special requirements imposed by difficult climatic conditions during the conservation season. It aims at confining physical treatment to the plant surface and applying it with varying severity along the length of plants and relative to crop yield, so that inherent differences in drying rates are reduced. To carry the objectives into effect, experimental conditioning rotors with open V-form beaters have been combined with reciprocating and drum-type rotary mowers. The beaters are forward-acting in the vertical plane and allow limited crop movement laterally and abrasive slip longitudinally. By guiding the crop cut-ends-first into the beaters, most work is done on the basal parts. The treated crop retains much of its structural strength and, therefore, can be formed into loose swaths resistant to settling. Relative to the control treatment of mowing followed by tedding or turning, the experimental mower-conditioners have given average drying rate improvements to the baling stage of up to about 60%; this was identical with crimping but lower than for flail mowing. Average dry matter recovery at baling was 10–15% above the control; this was also similar to crimping but higher than for flail mowing. Good resistance of experimentally treated crop to leaching by rain can be associated with a low level of deep tissue damage. Consideration is being given to applying the experimental beater rotor to the prevention of machine damage by foreign objects in forage harvesters.