AFTER regularly observing yield increases in his canola crops following a pasture rotation, WA farmer Mike Cameron realised how important nitrogen is in driving canola yields.
As Cherylton Farms general manager at Ryansbrook, Mr Cameron operates a 9500 hectare enterprise, which is 50 per cent sheep and Angus cattle production, with the remaining 50pc cropping.
The cropping program comprises canola, wheat, barley and oats, with canola taking up half the rotation, meaning it’s predominantly a canola-cereal rotation.
“The district is well-suited to canola, plus we need it for an agronomic break crop, because the ryegrass population can blow out if we grow too many successive cereal crops,” Mr Cameron said.
“What was interesting though, was that we were consistently at 0.5 tonnes per hectare yield increase in our canola following a pasture rotation, irrespective of variety and seasonal conditions.
“As we started to move further away from that initial pasture rotation, so more than about the second canola crop away from that original pasture and into more continuous cropping, the crop performance started to drop off significantly, even given industry practice nitrogen application.
“The available nitrogen had been used up in the early canola crops following pasture, so we were then finding a pretty substantial drop-off in the final canola yield, even though the same agronomic practices were in place.
It was a particularly important lesson for Mr Cameron, as while canola is a popular crop in the Great Southern, it’s not cheap to grow.
“Canola is increasingly becoming expensive for us to produce because of the impact of slugs and sclerotinia, a disease that really has only become a major issue in the past four years,” Mr Cameron said.
“If our yield targets are only 1.5 tonnes a hectare to 2t/ha, the cost of inputs is really quickly making it an uneconomical crop to grow, whereas if we’re sitting at 2.5t/ha, that extra nitrogen expense is well and truly justifying itself from a gross margin point-of-view.”
Deciding exactly when and how much nitrogen to apply to a canola crop in any given year is a strategic decision for Cherylton Farms, which purposely positions itself to optimise yield potential.
To read the full article visit pioneerseeds.com.au and click on the canola tab and look for Farm Profiles, then Western Australia.
