The future of fertilisers and waste recycling – why composting for soil type is so critical for farmers
by Adam Willson, Soil Systems Australia
Current challenges facing dairy producers
Over the last few years there has been a steady movement towards biological dairy
farming practices like use of manures, composting and remineralisation. Producers
have begun to realise that what we have been told about only needing nitrogen is
not the complete picture. The wheels have begun to fall off the cart and of particu-
lar concern to most is the decline in soil structure and herd health.
Some of the challenges faced by dairy producers include;
- Skyrocketing costs of production – both fertilisers and brought in feed
- Soils are becoming compacted – increased runoff and less utilisation of rainfall and irrigation water
- Pastures are not very palatable to stock – leading to reduced feed utilisation
- There is a strong dependance on brought in feeds
- Irrigation efficiency is low and expensive with increased electricity prices
- Herd health is declining and vet bills keep souring
- Researchers, consultants and industry don’t fully understand that all of these issues are related to declining soil health
The following article is not about pointing the finger but getting you the dairy producer to “wake up and smell the coffee”. Composting is one of many ancient farming practices that has been used for around 3000 years. Its role in improving the profitability of your business cannot be underestimated. It is not about throwing out the new and returning to a horse and cart. It is about learning to work with nature and forget about trying to control her.
What to do with your unwanted wastes and local resources
Have you ever considered the value of that waste material around the farm? Most of us ignore these piles until either they get too big or cashflow has forced us to look at alternatives. This is what happened in 2008 following the huge hike in oil and fertiliser prices. Farmers began searching for alternatives, recycling perceived waste and using local resources. It was the beginning of large scale on-farm composting and the germination of common sense.
Some of the local resources that can be utilised for on-farm composting include;
- Stockpiled cow manure
- Brought in chicken and pig manures
- Spoilt silage or hay
- Spoilt feed
- Separated effluent solids
- Liquid effluents and washdowns
Why produce quality compost?
It’s really a “no brainer” why dairy producers should be getting into composting and recycling of what are perceived waste products. Some of the benefits of producing quality compost include;
- The valuable humic and fulvic fractions produced in quality compost increases water use efficiency by up to 50% making your pastures and crops require less water. Humus holds up to 20 times its weight in water and acts like a sponge.
- By building this soil humus, the Cation Exchange Capacity (CEC) of soils can be increased by up to 70%. The CEC of a soil is a measure of the total amount of nutrients held in the soil.
This means that with the addition of quality compost, the soil can hold more nutrients and make these available to plants. As plant stress is primarily driven by nutrient and water
availability, points 1 and 2 are essential for financial success.
- Major reduction in weeds – weed seed doesn’t live through a composting process
- Applied fertilisers and minerals are made more bio-available when applied with quality compost. This results in less leaching of nutrients and improved financial outcomes. Reductions in your fertiliser bill of up to 25-33% is not uncommon.
- The soil becomes more friable leading to reductions in fuel by up to 25%. One example was a farmer who increased the speed of rippling his paddock with a Yeomans from 4km/hr to 8km/hr. This was due to the softening of the soil.
- There is an observed even production in pasture growth. There are less variations across the paddock on the same soil type.
- Increased Metabilisable Energy (ME) of pastures and improved utilisation of home grown feed. This means less brought in feed.
- There is little to no environmental or off farm effect in stark contrast to water soluble fertilisers.
The key thing to remember with these benefits is that they don’t happen overnight but rather
build upon each application.