Using EM on Your Dairy Farm

Using EM on Your Dairy Farm

The applications of Effective Micro-Organisms (EM) in dairy farming are centred around increasing soil biological activity of you soil, effluent pond and in your animals systems.

That means effective organic matter recycling, to build humus - the food for your soil and plants, improvements in nitrogen fixation and greater micorrhyzal activity, leading to more effective nutrient availability.

Using EM It should not be seen as a cost but rather an investment towards the future productivity of the farm and the saleability of New Zealand products as a whole. With increased chemical restrictions on the horizon for most Dairy farmers the time is right to start using the natural ecosystem of your soil and property to offset the input of less chemicals.

Potential benefits of EM use on Dairy Farms

An integrated programme using EM on dairy farms has the potential to give significant improvements of environmental indicators. Research both from overseas and NZ comparing EM in various applications related to dairying, and some related research on some of the individual micro-organisms that are contained in EM, demonstrate significant benefits in mitigating some of the negative impacts on the environment.

The areas that we can influence positively with EM are:

  1. Reduction of fertiliser inputs whilst maintaining production levels
  2. Reduction of nitrogen leaching and volatilisation
  3. Reduction of methane and greenhouse gas emissions from the environment including animals
  4. Increase in clover production

Key applications for Dairy farming

Below are some of the key applications of EM on Dairy farms. EM can also be used in a variety of other ways with positive effect. Please contact us and we can talk through you various options and come up with a detailed plan to use this technology effectively.

  • On pastures, apply 20 litres EM Ready to Use per ha with as much water as possible, target key periods such as early spring, and mid-summer through to autumn to combat fungal toxin periods, i.e. facial excema, and dead material accumulation.
  • Combine with fertilizer applications to increase efficacy of applications (10 litres EM Ready to Use /ha).
  • Using EM Ready to Use* in the washdown water will inoculate the effluent pond, improving pond function, reducing pond maintenaince (no crusting), and will generate a microbial liquid fertilizer, that will vastly improve those pasture areas that are irrigated with this fertiliser. This technique is an excellent way to use EM on your dairy farm.
  • Spray animal enclosures with 10% solution of EM Ready to Use* with water to control odours, to improve sanitation of bedding and housing. e.g. calves, pigs, hens
  • Apply EM Silage as an innoculant when making silage or baleage
  • Applying EM Animal to Cows and Calves at a rate of 10mls per cow per day  or 2mls per Calf per feed in milk – upto 4mls daily

Expected effects


With the addition of EM to the pasture we can expect an increase in yield (Daly & Stewart). This paper published in a refereed international journal showed that EM increased the yield of crops, and by assumption an increase grass growth could be expected with application of EM.

Fertiliser addition

When EM is combined with a half rate of fertiliser, the production is similar to a full rate of fertiliser on its own. The EM contains phosphate solubilising bacteria (PSB) this will mobilise P and enhance the breakdown of rock phosphate. The Photosynthetic bacteria have a denitrifying characteristic (Rhodopsuedomonas sp.) so this is likely to lead to less Nitrogen being leached and lost in a pastoral system using EM.

Effluent Pond

The unique mix of micro-organisms in EM will have a major improvement in pond maintenance with the surface crusting broken down and lowering harmful bacterial in ponds. For dairy farms that return their effluent to the pasture, then this is an excellent opportunity to get a double benefit from the EM, by;

The effluent becomes a carrier and a food source for the microbes and the target is the pasture and soil.
The EM will reduce the number of pathogenic microbes (E.coli, etc) in the effluent and make the pasture safer for animals grazing the pasture and staff applying the effluent.

Greenhouse gases

Trials have shown that adding EM to cattle slurry, pig slurry, and pig feed will reduce the levels of greenhouse gas emissions.

Cost of EM

EM applied at 20 litres per ha costs around $20 per ha. I would anticipate that around 100litres per ha per year would be optimum (5*20) that would cost $100 per ha. There would be further applications to effluent pond, and possible silage or feed. These costs would have to be calculated after the system is assessed. However the overall cost is not likely to be high relative to the positive gains.