Independent Pasture Trial - run by PastureFirst

The evaluation of EMNZ Microbial products on the yield and composition of irrigated pasture

Field Report (2021/2022)

Trial aim:

  1. To evaluate the effect that a range of EMNZ Microbial products has on irrigated Canterbury pastures and how they compare to traditional Nitrogen (urea) applications.
  2. Three aspect of pasture performance was evaluated:
    • Dry matter yield (kgDM/ha)
    • Clover content within the pasture sward
    • Root mass of the pasture


Dry matter Yield (kgDM/ha) Similar trends were seen across all harvest dates, with the high rate of Urea (80 kg/ha) consistently producing the highest yield. While the yield was not always significantly greater than the other treatments, it consistently produced the highest yield (Table 1). EM Soil & Crop + urea (40) and EM Plant Stimulant + urea (40), also produced consistently high results across all harvests compared to other treatments. EM Plant Stimulant + urea (40) and Urea Full (80) are the only two treatments that had significantly greater yield than the control at every single harvest. When looking at the combined total dry matter yield grown over the entire trial period (Table 2), all treatments except EM Soil & Crop (20) grew significantly more total yield than Control. Urea Full (80) grew the highest amount of dry matter, but this was significantly similar to that grown by EM Soil & Crop + urea (40), EM Plant Stimulant + urea (40), and EM Fert Enhance + urea (40). The addition of EM Soil & Crop, EM Plant Stimulant, and EM Fert Enhance to urea (40) significantly increased total dry matter production compared to urea (40) alone or the EM products alone. This indicates these products are enhanced when small amounts of nitrogen are added to them. 

Clover Content

There were some clear treatment effects on Clover Content within the pasture sward. As expected, the high rate of urea (80) reduced clover content at both assessment dates. This is often seen in high nitrogen use systems. The low nitrogen rate (urea 40) had no effect on clover content (Table 3). At the first assessment date, EM Soil and Crop and EM Plant Stimulant significantly increased clover content compared to untreated control and compared to both urea alone treatments. At the second assessment date a similar result was seen, although EM Plant Stimulant had similar clover content to untreated. At the first assessment date, EM Fert Enhance did increase clover content compared to untreated, but this was not statistically significant. It did however significantly increase clover content compared to the urea only treatments. A similar result was seen at the second assessment date, but the increased clover content was seen only against the high rate of urea. The addition of 40kg/ha Urea to the three EM products did reduce clover content but not statistically


All three EM products showed that they have a positive effect on pasture production. While on their own the level of dry matter production was lower than that of high rates of nitrogen, in combination with lower rates of nitrogen they provide significant benefits. The total dry matter produced by combining each of the three EM products with 40kg urea/ha, was equivalent to that grown by applying 80kg urea/ha. This means that farmers can reduce their nitrogen inputs, but can grow equivalent amounts of pasture by adding in one of the EM products. This has significant production, economic and environmental benefits. The increased level of clover being able to be produced by implementing the above system, compared to high nitrogen systems, will also be a long-term benefit for pastoral farmers.

To download the full report - click here

Foliar Pasture Trial

This replicated trial in Canterbury, New Zealand was designed to determine the effectiveness of EM treatments at improving biological foliar products in Pasture. The Foliar products were leading brands of Seaweed and Fish Hydrolysate. EM was applied at 10L per ha. Results showed that EM gave a significant yield response when added to both Seaweed and Fish compared with the treatments excluding EM. 

Visual Soil Assessment on Pasture

What is a Visual Soil Assessment?

VSA is a method of assessing the health and quality of a soil. Doing a VSA will give an effective assessment of the condition of the soil and therefore the performance of the pasture or crop. VSA is based on the visual scoring of key bio-physical indicators of soil quality. The indicators used were:

  • Soil Structure = is very important on a whole heap of levels including aeration, water holding capacity, root penetration, nutrient holding and supply and many others. It was measure on a scale of 2= Good, 1 = Moderate and 0 = poor condition
  • Soil Smell = A good indicator of the activity of soil life and therefore soil health. It was measure on a scale of 2= Good, 1 = Moderate and 0 = poor condition
  • Root Depth = the depth of soil that roots can potentially exploit before reaching a barrier to root growth. It was measure on a scale of 2= Good - >800mm depth, 1.5 = Moderately Good - 600-800mm, 1 = Moderate – 400-600mm, 0.5 = Moderately poor – 200-400mm and 0 = Poor condition - <200mm
  • Soil Colour = A darker coloured soil generally indicates a higher level of organic matter and humus. It was measure ona scale of 2= Good, 1 = Moderate and 0 = poor condition
  • Soil Porosity = Looks at the movement of air and water in the soil. It was measured on a scale of 2= Good, 1 = Moderate and 0 = poor condition.
  • Earthworm numbers = a straight count of earth worm numbers detected in a spade full
  • Brix Readings = Brix gives farmers a simple tool to measure whether the plant is properly nourished. Brix is a great measurement of pasture quality

Results of the VSA

The technique used was to take a spade square sample from three reps for the control treatments and 3 reps from the EM treatments. For the brix readings I took 3 readings per sample plot. The results of the VSA provided significant evidence that the EM treated plots were of a much better quality that the non EM plots. The soil structure was immediately noticeable as better on the EM treated plots with more friable aggregates and more soil crumbs clinging to roots. The smell was pretty good on all of the plots but was excellent on 2 of the EM treated plots. One of the biggest differences was the colour; the EM treated plots had a darker looking soil showing the benefits of the additional organic matter breakdown and microbial activity. The roots also tended to be longer on the EM treated plots. A good example of this is the below picture:

In this picture the EM plot has darker soil. You can also see more fibrous roots and a better crumb structure.

In addition there were more worms in the EM treated plots although these were still lower than what we would have like to have seen. Another very intriguing element was that the brix was significantly higher in all of the EM plots with the average reading being 2 points higher.


Overall we were really happy with the results of this VSA, this is a great indicator of soil quality and has shown EM has a positive impact on the soil ecosystem.



Pasture Renovation

EM can enhance pasture renovation through breaking down old pasture residues creating food for the soil and enhancing soil biological activity. It will also enhance germination of the new pasture and pasture persistence.


The image to the right illustrates a paddock trial we ran with a farmer showing the effectiveness of EM in pasture renovation. The farmer used a double spray technique with roundup to kill old pasture and then direct drilled new pasture. EM was combined with the Roundup spray at 10 litres/ha. The farmer did one block with EM and one without and the below photos were taken 3 months after emergence.