SYSTEMS WINTER CROP RELIANCE
Regen ag coach questions winter crop reliance Otago-based Siobhan Griffin suggests dairy farmers could use bale grazing which would help with paddock recovery times. Karen Trebilcock reports.
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egenerative farming coach Siobhan Griffin is questioning dairy farmers’ reliance on winter crops in the South Island. “I have not found a farmer who can show me on paper that it pays in the first place if all opportunity costs are included,” she said. “For example, a 250ha dairy farm where cows are not wintered off, with 10% in fodder beet, could be losing out on tonnes of feed, as the 14-month crop has to be planted in September. “You have no grazing available for a full year starting in September when you planted the crop plus one and a half to two extra months while you wait for the 44
renewed paddocks to be ready to graze. “Last year some paddocks in the south couldn’t be renewed until December so they weren’t grazed for the first time again until February.” She said in 14 months, 338 tonnes of dry matter of grass could have been grown on the 25ha (11.5T DM/ha). “This opportunity cost could be higher because the 14 months covers two months twice (September and October) when the paddock is not available for grazing and they happen to be the months where pasture normally starts to grow very quickly.” If 20T DM/ha of fodder beet was grown per hectare, 500T DM overall, the winter
crop has still grown more feed (162T DM), but Siobhan said the cost was high. “Assuming costs of $2300/ha, the extra 162T DM has cost Regenerative farming $57,500 or $354/T coach Siobhan Griffin DM, not far below the cost of feed grain.” If the season had not been kind, and a 15T DM crop was grown, then it would only be an extra 37T DM compared with if the paddock had been kept in grass. “However, this is assuming your pasture was grazed at the three-leaf stage.
Dairy Exporter | www.nzfarmlife.co.nz | July 2021
