More than just N, P, K
By building good levels of soil organic carbon and supporting soil biology, nutrients are much more easily and effectively transferred through plants and into the food and fibre on which we depend.
Giving back through compost and green manure crops
Although these natural cycles are inherently regenerative, by harvesting our food and fibre and moving our stock we are breaking the cycle. We must consciously give back to the soil to ensure nutrients and minerals do not become depleted.
Bill and Rhonda Daly of Milgadara on the NSW South West Slopes, and Cam and Roxane McKellar of Inveraray Downs in the NSW North West Plains are responding to any loss of nutrients from harvested products, by the regular application of organic compost. This allows for recycling of off-farm nutrients by re-introducing composted materials back on to the property.
The Dalys have restored their soil structure, chemistry and biology through applying specially formulated humus compost. As a result, they have increased soil organic carbon (SOC) levels, improved cation exchange capacity (CEC), their pastures are more diverse and prolific and their crops are producing greater yields. The Dalys have also experienced an improvement in the quality of the wool their sheep are producing and lambing percentages have increased. This could potentially be linked to the improved nutrition in their pastures.
The Dalys are delighted by the outcomes they have achieved through the application of humus compost and are so enamoured with the product they have developed that they seek to share it with others through their business YLAD Living Soils.
Improved plant nutrition is also linked to higher test weights in crop production. As a result of improved soil structure, nutrient cycling and water holding capacity, it is possible to achieve the same yield with lower applied nitrogen. Improved translocation and allocation of other nutrients to the grain, as well as improved water and carbohydrate transfer occur when plants are less moisture stressed – conditions generated by healthy soils.
On Inveraray Downs on the Liverpool Plains, the McKellars are regenerating what used to be some of Australia’s best soils, which had become degraded through cultivation and use of inorganic fertilisers and biocides. The McKellars have re-designed ecological cropping practices by altering crop rotation, applying compost and introducing stock into production – all of which are contributing to restoring essential biological processes, nutrient cycling and healthy soils. As a result, they now produce better quality and more healthy and nutritious food – more sustainably and with lower input costs.
Cam and Roxane are capturing increased nutrients such as nitrogen from plant growth through incorporating green manure legume crops, and through the retention of crop stubble. Consequently, greater soil microbial population response is promoted, which in turn feeds improved cycling of the other nutrients needed for plant growth. Under the previous conventional management system, this would have been lost to burning and oxidation.
By moving from synthetic to compost-based minerals for nutrient replacement, the McKellars are now also adding trace elements, organic matter and biological by-products of the compost process that contribute to soil fertility over and above simple nutrient replacement.
Hopefully the examples over the last few weeks have demonstrated the range of activities that can be taken to improve soil health. You don’t have to do them all or all at once, but the important message for all our farmers and land managers is just to start. Any step towards improving your soil health is a step in the right direction.
Leave a comment or contact us if you need any more support in getting you started.
Wishing you healthy soils over the holiday season, in 2013 and beyond. Tune in early next year as we start to explore the importance of water management and what we can do to use it more effectively.
The Soils for Life Team