Sub clover is a key species to improve dryland hill country.
Direct drilling maize could save you hundreds of dollars a hectare with no loss of yield, long-term trial work by FAR in Waikato shows.
Conventional tillage costing $500/ha to establish a crop has averaged 12.2 tonnes/ha of grain, strip-tillage costing $360/ha has done 12.7t/ha, and direct drilling costing $150/ha at 12.3t/ha, FAR’s Alistair Holmes told conference delegates.
He also presented data showing a first maize crop after long-term pasture requires little or no nitrogen fertiliser, and urged growers to rotate crops rather than planting maize in the same paddock year after year.
Repeat crops increase weed and pest problems, and the risk of resistance to agrichemicals, he said. They also mine soil fertility, with silage crops in particular removing large amounts of organic matter.
“It’s key that you maintain soil organic matter with cover crops or reduced tillage,” he said.
A cultivar evaluation system similar to the Cereal Performance Testing (CPT) system was initiated last summer with sites in Waikato (two), Bay of Plenty and Canterbury. Manawatu and Rangitikei sites will be added this summer. Results from last season were to be published shortly.