Jeremy Talbot, from south Canterbury, recently called three local contractors to get a quote on ensiling 20ha of grass, either as balage or pit silage.
“There wasn’t much difference between the contractors, but you’d be shocked at the difference in cost between the methods,” he said.
“And it’s not just about the cost: the pit silage will keep much longer, is cheaper to feed out, and will be much better quality if it’s made properly.”
Averaging the quotes from the three firms, which were based on a 2-3km cart from paddock to stack and 28% dry-matter, fine-chop pit silage came in at just 7.5c/kg drymatter (DM) covered. Tube-wrapped squares were 20c/kg DM and rounds 29c/kg DM, while individually wrapped squares and rounds were 21c/kg DM and 30c/kg DM respectively.
“Admittedly that includes cartage for the balage but there aren’t many people who make the bales and feed them in the same paddock, so you’ve got to account for that cartage somewhere.”
Talbot said international manufacturing standards dictated bale-wrap must deteriorate under UV so it biodegraded within two years. Consequently, balage was often worthless beyond that, forcing a use-it or lose-it scenario.
In contrast, stack covers aren’t subject to the same requirement and well-made pit silage could be put away for decades if needed.
“Those farmers paying 30c/kg DM just to make balage with grass they’ve grown could be buying in maize or cereal silage for much the same money, feed and ensiling included,” he said.
“These feeds increase production when fed with grass because they balance the diet better and, because they reduce the overall nitrogen content of the diet, they reduce nitrate losses in urine so it’s better for the environment.”
Alternatively, dairy farms could grow some maize or another cereal for ensiling on the milking platform as part of a grass renewal programme.
“If they did this it would help balance feed supply over the year, and improve the farm’s water use efficiency. Ryegrass stops growing at around 26C regardless of how much water you throw at it but maize loves that heat. Because these crops are so much more efficient users of water you could cut irrigation requirement 40-50%.
“This system of conserving spring grass while feeding out wholecrop silage made the previous summer or autumn, then using the conserved grass to bridge the summer feed deficit, works in wet, dry and normal years and produces about 20% more milk. What’s more, because increased starch in the diet boosts milk protein, that milk’s worth 10-15% more and you reduce the farm’s environmental footprint because the cows aren’t excreting so much nitrogen in their urine.”
Talbot acknowledged in the current climate bank managers would need some convincing that buying in feeds such as maize now, or funding a crop next season, was the right thing to do instead of culling cows but he was adamant in the short, medium and long-term it was the most economic and environmentally sustainable thing to do.
“We’ve got to change our ways and at the moment Dairy NZ has only got it half right. Yes, you need to maximise use of pasture, but you also need to make best use of that pasture and that means being smart about when and where you use it and, if necessary, feeding something else with it.
“As renowned economist Keith Woodford recently pointed out in his blog, it’s essential to maintain production in this downturn and it’s the system 3 and 4 farms that will survive because they have the greatest ability to pay interest on their debt.”
