What the research says
Plantain, specifically Ecotain™, has consistently shown reduced nitrate leaching through the Forages for Reduced Nitrate Leaching and Greener Pastures projects, and research now continues via the Plantain Potency and Practice Programme. Research at Massey University and through the NZ Agricultural Greenhouse Gas Research Centre has also shown potential for Ecotain™ plantain to reduce both nitrous oxide emissions and methane.
What N leaching reductions you could expect
Experiments located at Massey University in Palmerston North have shown it is possible to reduce nitrate leaching by between 20 and 60% from pastures containing 30-50% Ecotain™ plantain. The amount of leaching reduction from Ecotain™ will depend on the soil, climate, and farm system setup.
Why Ecotain™?
To date, virtually all published evidence of the effectiveness of plantain for reducing nitrate leaching has used the Ceres Tonic or Agritonic cultivars of plantain. These cultivars are marketed by Agricom as Ecotain™. There is evidence of variation in the effectiveness of different cultivars for some of the drivers of N leaching described below2,3. A new Evaluation System is available for assessing the effectiveness of cultivars for achieving reduced nitrate leaching. DairyNZ recommends that cultivars of plantain should meet the standards of this Evaluation System, before being recommended for environmental purposes.
How Ecotain™ plantain reduces nitrate leaching
Over the past decade, research has provided strong evidence that Ecotain™ plantain can reduce nitrate leaching and nitrous oxide emissions. The plant is thought to work in four ways as shown in Figure 1 below.

Figure 1: Nitrogen cycle and the four modes of action of Ecotain™ plantain.
Action #1: Dilution effect
When Ecotain™ is included in the diet, the number of urination events and total urine volume increases, and consequently the urinary nitrogen concentration decreases.
Action #2: Partitioning effect
Nitrogen consumed by ruminants is partitioned into different pools including milk, faeces, and urine. The portions of N in each output increase or decrease depending on the diet. When Ecotain™ plantain is included in a cow’s diet, the portion of nitrogen intake partitioned to urine decreases and the amount partitioned to faeces and milk increases, when compared to perennial ryegrass7,5.
Actions #3 and 4: Direct and indirect N retention effects
Research using lysimeters has shown that Ecotain™ plantain can retain nitrogen in the soil, providing plants with more time to use the excess nitrogen in a urine patch, and reducing loss via leaching and nitrous oxide gas.
Plantain in Overseer FM
The total effect of Ecotain™ plantain cannot yet be predicted in models, however, it is possible to estimate the effect of reduced N concentration in the urine patch through dilution, and reduced urinary nitrogen excretion via partitioning, using available data sets. Modifications to Overseer FM have therefore been possible to accommodate these effects11 as described below. The N retention effects will be added to Overseer when the required data is available, and this will likely increase the magnitude of the modelled N loss reduction.
Work is currently underway in the Plaintain Potency and Practice Programme to model the full effect of plantain in Overseer.
Can plantain have an effect on my GHG emissions too?
Plantain has been shown to reduce nitrous oxide (N2O) emissions from the urine patch by 53% in pastures with 30% Ecotain™1,2. This finding is from one experiment. More work is currently underway to provide a greater understanding of the potential for plantain to reduce N2O emissions.