An independent review of DairyNZ’s plantain research programme shows it is on track to achieve its objectives, while the use of plantain to reduce Nitrate leaching is being backed up by farmers and regulators. The review found that the scientific inquiry is of a high standard and leading to strong evidence that supports the adoption of plantain as a tool to reduce nitrate leaching.
DairyNZ Chief Science Advisor Bruce Thorrold says the review confirmed that the evidence strongly supports Ecotain™ plantain reducing nitrate leaching, helping to improve waterways.
“Including plantain at 20-30% of a grazed ryegrass/clover mixed pasture has resulted in average annual nitrogen leaching reductions of 26% at Massey over four years, and 23% at Lincoln over two years. Pasture and milk production has been similar from pastures with and without plantain,” he says.
“Prior and current research shows us plantain is a high impact and viable pasture-based option for reducing nitrate leaching. There are other pasture species that should be explored, but we are currently focusing on plantain. This focus gives us the opportunity to explore the ways that pasture plants can impact the nitrogen cycle,” says Dr Thorrold.
“There’s more research to be done. The review confirmed the need to understand the observed soil mechanisms and how they affect N leaching in different soils and climates, so these effects can be included in OverseerFM, and be recognised in farmers’ N budgets,” he says.
The knowledge gained will also help validate plant testing methods and models for investigating other species and cultivars in the future.
Plantain is now recognised as an N leaching mitigation option by regional councils in Canterbury, Horizons, Waikato, Southland and Bay of Plenty, where N leaching limits are in place.
Welcoming the review, Tim Davie, Science Director at Environment Canterbury, says it’s great to see the progress in the science backing the effectiveness of plantain. “ECan recognises plantain as a valuable tool for helping farmers meet nutrient limits and minimise their environmental impact,” he says.
Stephanie Fraser from Bay of Plenty Regional Council explains that Lake Rotorua is subject to strict nutrient management regulations aimed at reducing nitrogen levels to improve water quality of Lake Rotorua. “The farming community is progressively embracing plantain, with about 3/4 of dairy farmers in the catchment modelling a transition to the use of plantain by 2032,” she says.
The Council recognises the impact of plantain in OverseerFM. “Plantain is proving to be a valuable tool for nitrogen mitigation. It helps farmers comply with nutrient regulations, while maintaining productivity. As farmers continue to navigate the complexities of nutrient management, plantain seems to offer a promising solution that aligns with environmental and regulatory goals,” says Ms Fraser.
Lake Rotorua catchment farmer Richard Fowler introduced plantain to help meet nutrient management regulations. Working toward his 2032 limit of 40kg N/ha of nitrogen loss below the root zone, plantain has been a key tool in reducing nitrogen leaching on his farm.
“I have been broadcasting plantain seed over the farm with fertiliser applications over the past five years. I didn’t see much in the first summer, but it started showing up in the autumn and the following season. It seems to be cost-effective and working well in our catchment,” says Richard.
Work with partner farms across the country shows that plantain can be introduced into new and existing pastures. Maintaining target plantain levels requires on-going re-seeding by direct drilling or broadcasting the seed, e.g. with fertiliser, every 1-3 years.
Richard’s recommendation to other farmers is to consider plantain and to try adding it to their fertiliser applications. OverseerFM modelling shows a 6kg/ha (14%) reduction in nitrogen leaching from the 20% plantain pastures, which contributes significantly towards Richard’s target.
The mid-programme review provides an independent assessment of the programme (a seven-year research initiative led by DairyNZ and using PGG Wrightson Seeds Ecotain®) and provides recommendations for future direction and funding priorities. The funding partners are MPI, DairyNZ, PGG Wrightson Seeds Ltd., and Fonterra.
This story also appeared in Farmers Weekly on 29 November 2024.
Media contact
Jacob Quinn
Principal Corporate Communications Advisor
p: 027 716 4197
e: jacob.quinn@dairynz.co.nz