Open AccessA MIXED CROP STOCK FARMLET ON A ROSTERED WATER SUPPLY
Author(s) -
R. Stoker,
C. G. Janson
Publication year - 1985
Publication title -
proceedings of the new zealand grassland association
Language(s) - English
Resource type - Journals
eISSN - 1179-4577
pISSN - 0369-3902
DOI - 10.33584/jnzg.1985.46.1706
Subject(s) - hectare , irrigation , pasture , sowing , agronomy , crop , environmental science , crop yield , agriculture , biology , ecology
The on-farm water supply on the Mid Canterbury irrigation schemes of 230 litre/sec for one day per week for every 80 hectares of farm area has traditionally been considered capable or irrigating only about one half or two thirds of the total farm area. Many farmers have border dyked about this proportion of their farms leaving the remainder dryland. In 1978 a farmlet with the whole area prepared for irrigation but still subject to the normal limitations of the rostered water supply was set up at Winchmore. Half of the area is in cash crop. Through a careful selection of crops and sowing dates each crop can be irrigated for maximum yield without exceeding the water allocation. On the remainder of the farmlet half the area is in grass clover pasture and half in lucerne. The water supply permits this to be irrigated at four weekly intervais or more frequently before and after the period of crop irrigation. Crop production on the farmlet has only been average. For instance wheat and barely have generally yielded between 3.5 and 5 tonnes per hectare. Soil moisture monitoring suggests that limitations have not been imposed by the irrigation regime itself but by such factors as late sowing the crop or undersowing with pasture. Over the three year stand life herbage production has averaged over 11000 kg/ha with annual yield of lucerne exceeding that of grass/clover pasture in the first season ex crop. Stocking rates between 13 and 15 ewes/ha measured over the whole farm area or 26-301ha on spring grazing area have been adopted with large variations in production. With recent changes in the relative economics of sheep and cropping it has been decided to increase the emphasis on the crop aspect of the farmlet. The cropping area has been increased to twothirds. The farmlet is still run under the limitations of the rostered water supply but water may now be transferred from the herbage to crop at critical times. At the expense of small losses in herbage production crop yields will be increased substantially by eliminating such practices as late sowing dates and undersowing. Keywords: Irrigation, roster, crop, stock.