Russell Phillips is embarking on a journey to raise the content of plantain on his Te Rehunga farm and supporting a research project to start a catchment-wide action to plant farms in 30% of the N-reducing forage. Jackie Harrigan reports.
Russell Phillips has been dairy farming at Te Rehunga, south of Dannevirke since he was 21, on a farm that incorporates his grandparents’ original dairy block. But the 62-year-old sees the future of the whole Tararua region threatened if they can’t find a way to bring down the level of nitrogen leaching from his and others’ farms or mitigate the effects well enough to get a consent to farm from the Horizons Regional Council.
Joining in with a Dairy NZ and Horizons regional council initiative to encourage farmers in sensitive catchments (like Russell’s Upper Manawatu River catchment) to establish and maintain a 30% plantain sward is both “about survival” and “brings a benefit to the whole community”, Russell says.
Russell is one of 135 dairy farmers in the Tararua region farming without a consent. He says he had just started the process when Horizons called a halt to the process, having received a legal challenge to their implementation of their regional One Plan.
Baseline modelling of the unconsented farms show that to achieve Horizon’s Year 10 targets for N loss, the median farm must reduce N-loss by 50%, a level acknowledged by both Horizons and industry sector groups as unviable to farm businesses.
‘We need to maintain our operation and asset value and secure the value of our properties so that the community remains viable and the social impact of farming remains.’
Russell agrees, saying the impact has been measured at a loss of $70 million in annual milk sales and about 300 jobs within the community, with huge social impacts. Recently the figures were updated by independent consultants at a higher level, and the absence of that money flowing into Tararua businesses would be devastating, he says.
Meeting the N-loss levels demanded under Table 14.2 of Horizon’s One Plan would force all farmers to lower their stocking rates decreasing gross income by 30-40%, Russell says.
“We need to maintain our operation and asset value and secure the value of our properties so that the community remains viable and the social impact of farming remains.”
The Plantain Project could be a “game-changer”, Russell says, who has thrown himself into helping with the co-development of the project, hosting trials on establishment and persistence of the plantain on his property.
The premise is that catchment-wide planting of plantain at scale (around 30% Ecotain sward across all farms within the catchment) will show that, in conjunction with other mitigations, N-losses can be reduced so that farm business viability is maintained.
“A number of farmers in the Tararua region already have plantain in their farm systems, but in the big picture, how do you get 30% Ecotain sward across all the land?
“And how do you maintain the ratio year on year? There are different challenges for different farms in doing that.”
The science is locked in, he says, with the advantage of plantain as a mitigation being that it allows the farm to continue as a pasture-based system without investing heavily in infrastructure. Adoption of Ecotain by beef operations would also reduce the total N loss across the catchment, Russell says.
Research into plantain has shown it reduces N leaching by:
- Dilution of the N urine concentration
- A change in protein metabolism
- Secondary compounds act as nitrification inhibitors
- Increased uptake of N.
Along with working out the mechanics of lifting the plantain proportion to 30% of pasture, a big driver for the Phillips is to prove that the sward can be managed to increase the economic return for the farm.
“We want to prove the plantain can increase our economic return, not just help us meet compliance – making more money is a much more compelling reason for farmers to embrace the plantain project,” Russell says.
“If you go to the trouble and expense of establishing it, you want to see a return, not just stand still.”
In January 2018 the Phillips direct-drilled plantain at three different rates with 150kg/ha DAP after the cows grazed to a level of 1450kg DM/ha. Paddocks were sown at 4kg, 6kg, 8kg and 12kg/ha Ecotain, and the levels of plantain establishment are now being monitored by Agricom with pasture cages.
“We tried it in January to see how it would establish when it’s drier,” Russell says.
“Every farmer varies in their ability to do the direct drilling thenselves, and if they are relying on contractors, we need to think about the windows of time that will work to get good establishment.”
Trialling of different months for direct drilling will help establish the size of the planting window.
“The bigger window we can find to get success, the easier it is for farmers to adopt a plantain establishment and management system that suits their place.”
Direct drilling in January resulted in a 35% establishment in the 8kg Ecotain block; now the Phillips are thinking about management, to maintain it in the sward.
For the first grazing in late February, one paddock was mown before grazing to avoid pulling out the young plantain plants, and another paddock grazed without mowing, to track the effects.
On another part of the farm, autumn planting in March of a mixed ryegrass and clover permanent sward with 5kg plantain /ha has been established and will be also monitored for plantain percentage.
The Phillips grow 50ha of chicory as a summer crop, instead of turnips and rape, of which 25ha is resown into annual ryegrass and plantain and the other 25ha into plantain and permanent ryegrass sward. Plantain will be added into these mixes too.
“We will also trial oversowing the plantain by broadcasting at different rates and measure the sward percentage, if we could oversow one third of the farm each year – would that be enough to be compliant?” Russell says.
“For me, every farmer has to say what’s the annual cost to maintain that percentage of plantain to achieve that reduction of N? It will be different for each operation.”
Establishment, maintenance and weed control are all factors in the mix, which for the Phillips is complicated by farming in a giant buttercup area where they blanket spray the whole farm to keep the rampant weed at bay.
“We need to find alternatives though, because Valdo/Preside kills the weed but also kills plantain.”
Russell is working through other regimes with agronomist, Mark Evans from PGG Wrightsons and wondering if a lower rate will kill young buttercup plants but not the plantain.
“We will experiment with a suite of other chemicals, but with great consideration of the environmental effects.”
Other mitigations the Phillips have used on their Dannevirke farm range from fencing off and planting all waterways, through to using different forms of N and limiting application to 18 units at a time and spraying effluent over 100ha.
To meet future compliance in effluent management, Russell says there will be a need to invest in a new storage facility to delay application through the wet autumn and spring periods.
The family have invested in two cow shelters, to allow them flexibility to winter cows off the pastures and cut down on leaching of nutrient. Cows were previously wintered on their runoff on fodder beet and rape crop. This has been their first winter using the barns, and Russell is very pleased with how the cows seemed to enjoy being warm and dry and calving in the shelters.
Fodder beet fed in situ was swapped out for 15ha of sugar beet grown and lifted by a new imported second-hand beet lifter from Germany. The sugar beet is fed at a rate of 4kg/cow in the winter diet and at 3kg/cow in the milkers’ diet.
“We took a calculated risk investing in the shelters, but the research we have done shows a 40-50% reduction in N footprint and there are advantages around labour savings, cutting heat stress in a hot summer, and efficiencies of feeding on the feed pad rather than in the paddock.
“And there is also a risk in doing nothing.”
The aerobically composting floor of the latest shelter built could be a game changer too, Russell says.
While the 500mm of sawdust needs to be ripped twice each day, the aerobic composting means the substrate heats up to 40-45C and causes evaporation of liquid alongside composting of solids, and the top 200mm will be taken off and used as fertiliser at the end of the season.
“We are just learning about the substrate – but it’s working very well thus far.”
Route to consentable levels
While plantain is not a silver bullet, it could present one option in a system designed to help meet the conditions of consents in the future, Dairy NZ’s Rob Brazendale says.
Catchment leader Adam Duker agrees, saying the catchment-wide Plantain Project sees Dairy NZ supporting farmers onfarm to maintain a pasture-based system while reducing their footprint as much as possible.
“The plantain introduced at this level could help unconsented farmers reach a consentable level while giving consented farmers some headroom to continue refining their system.”
Horizons regional council head of regulation and strategy Nick Peet reports the council are working on a calculator which when robustly peer-reviewed would help calculate the amount of plantain required and amount of N mitigated.
The Phillips family are one of the innovative farmers helping co-develop the establishment and management protocols around maintaining 30% plantain in a sward across the catchment.
The challenges of the plantain project include the way the forage behaves like a hybrid rather than a perennial in a mixed sward and designing a farm system to achieve a diet of 30% plantain in the January-May period when N uptake from soil is slower, higher rainfall and more common drainage events mean higher rates of leaching.
Research at Massey and Lincoln Universities is focused on proof at paddock scale and farm modelling will be completed by December on the amount of plantain required in the diet and the estimated reduction in N leaching in the Tararua district.
Farm: Waka Dairies, Te Rehunga, Dannevirke
Owners: Russell and Karen Phillips,
Milking platform: 245ha
Cows: 2018/19 season 900 Kiwicross cows, generally spring calving, last season 850 cows
Production: 2017/2018 season 850 cows @535kgMS/cow. 3.5cows/ha, 1850kg MS/ha
System 5 operation,
Harvesting 13 tonnes pasture/ha
Dietary inputs: In-shed feeding grains and meal, sugar beet and whole crop barley silage on feedpad (grown on runoff), chicory cropped for summer feed
Employees: Operations manager Michael Phillips, farm manager Andrew Evans, five other staff.