Teagasc’s Dr. Dermot Foristal has highlighted the value which effective crop rotation can deliver on Irish tillage farms.
They include securing of yield benefits in the range of 11% to 19%. Kicking-in here is the disease break, which rotating crops can deliver.
Despite the fact that many tillage farmers did not get the opportunity of planting as many winter crops as they would have liked last back-end, Forristal is urging growers to keep their rotations as structured as possible in 2024.
He explained: “Break crops also give us different weed control advantages. The time of sowing of the different crops and their growth nature means there might be different impact on the weeds that are there.
“But growers can also use different chemistry on the weeds within the crop.”
Other benefits come in the form of machinery inputs, workload, nutrient use efficiency when legumes are included within the rotation, and the potential to access more markets.
Cost and value of crop rotation
Forristal is also advising farmers to assess the cost and value of the rotation based on the rotation itself, not on single crops within that rotation.
“We need to choose our crop mix carefully because the amount of break crops in the rotation, if you have a market for them and if your land is suitable, may have an impact on profit,” he said.
Using data from the 2024 Teagasc Crops Costs and Returns and average yields obtained over the past seven years, the Teagasc researcher has confirmed that yield benefits of 15% are seen from first wheats sown after a suitable rotation.
For this specific option, as opposed to continuous wheat, this results in a margin benefit of 82%.
When spring barley grown continuously is compared to a suitable rotation consisting of a first-crop winter wheat, winter barley, oilseed rape, winter wheat and beans, additional margin benefits are observed when the average margins over a five-year period are compared.
“The difference between continuous spring barley and the rotation in this case is €203/ha,” Forristal said.
“That’s how the rotation crops can be optimised, provided growers have suitable markets and their ground is suitable for those crops.
“In the long-term, tillage farmers need to look at the sustainability factor, particularly in terms of some of the challenges we’re seeing with grass weeds and herbicide resistance.”
Forristal said that when adopting different crop establishment systems, the use of rotations is hugely important as part of a suite of measures linked to integrated weed management.