Four-Year Trial Confirms Plantain Cuts N Losses 33%
A four year trial has reaffirmed that mixing plantain into dairy pastures can help reduce nitrogen losses to freshwater while maintaining milk production and profitability, say researchers.
A network of 18 study sites, ranging from Lake Hawea in Central Otago to Waiakaia near Gisborne, was established through the Hill Country Futures Partnership Programme. The $8.1m programme is co-funded by Beef + Lamb New Zealand, the Ministry of Business, Innovation and Employment, PGG Wrightson Seeds and Seed Force New Zealand.
The study’s aim is about future proofing the profitability, sustainability and wellbeing of New Zealand’s hill country farmers, their farm systems, the environment and rural communities. It incorporates traditional science research, farmer knowledge, social research and citizen science and has a strong emphasis on forages and providing decision-making tools to help farmers select the best forage option for different land management units.
Researchers undertaking the work are from Lincoln University, Manaaki Whenua -Landcare Research and Massey University.
Dr Suzi Keeling, sector science strategy manager for B+LNZ, provides scientific oversight for the programme and says a key focus has been resilient forages for the future.
“The programme provided an opportunity to test different forage combinations in a number of research and commercial farms around New Zealand,” she explains. “Being able to do this in a range of different locations has ensured we have accommodated what farmers are really interested in, while also answering important science questions.”
The 18 locations include 12 forage trial sites evaluating different combinations of forages. There are six sites capturing soil temperature and moisture data (some overlap with forage trial sites) and three focused on assessing native plants as potential forage.
“Through the forage trials, we are looking at how we support farmers to have resilient forages into the future,” Keeling adds. “It is capturing real data on farms to make it tangible for farmers to see how forages perform in different locations. We are also building a large dataset to develop tools that farmers can use to help them select which forages are most ideal for their situation.”
A further outcome of the programme has been the AgYields national forage database. This is a central repository for all pasture and crop yield data collected in New Zealand to help farmers and farm consultants with decision-making around pasture planning.
The soil temperature and moisture microscale indicator projects recognise that hill country farms are diverse landscapes. These are designed to enable farmers to use farm scale mapping to assess which forage mixes are likely to do well in specific areas of their farm.
Research around native shrubs looks at the potential of natives for sheep fodder, in terms of palatability, digestibility and protein characteristics. The focus is on improving animal productivity, animal welfare, biodiversity and soil health while mitigating soil erosion and climate change.
“An important aspect of the programme is ensuring our investment is informed by good information,” Keeling says.
This allows farmers to know what forages suit what soil types and environments, when to sow forages and what they need to be thinking about in terms of sowing rates and fertiliser applications.
“It means that when they are planning to establish pasture to feed their animals, they have the best information available to do that as efficiently as possible. It removes the risk of ‘taking a stab in the dark’.”
Keeling says if farmers are producing forage of better quality and yield that integrates well into their farm system.
“It allows you to make smart decisions around pasture management and hopefully get a longer lifetime out of your forages. That means less frequent need for forage renewal of pasture, which also has good benefits for soil health.”
Findings from the trials have been made available as factsheets through the Beef + Lamb New Zealand Knowledge Hub. Plans are also underway to create a series of ‘how to’ videos providing guidance on pasture management.
Keeling says there have been many positive outcomes from the research.
“Many of these are also now in scientific literature, so they have been through a peer review process. That gives us real confidence around the level of rigour associated with the work and that the information in the B+LNZ factsheets is robust and useful for farmers.”
