We conducted a Biochar Trial under non irrigated pasture. With 100 and 200kg of biochar with 100 and 200kg of Single Super. The full report can be found here
Overall the biochar had a positive effect on both the plant biomass and minerals in the soil, with a statistical difference was detected in the plant minerals caused by biochar.
The biochar in general improved pasture biomass. In many cases the half fertiliser rates (100kg of urea) showed similar growth to the full fertiliser rates (200kg of Urea) indicating that the biochar may be holding nutrients in the soil allowing greater pasture growth.
Over 8 reliable pasture cuts there was more often an interaction between biochar rates than there were fertiliser rates and sometimes an interaction between both. When the seasonal factors were not limiting (ie November) it was more difficult to find a statistical difference.
There was a general pattern of mineral retention in the soil with added biochar and the mineral retention was higher in the soil with half fertiliser treatments rather than full fertiliser treatments. These results were not statistically analysed.
PLANT TISSUE TESTS
There was an increase in the amount of manganese in the plant tissue in the biochar treatments. This was the only statistical difference in minerals found in the plant tissue caused by biochar.
No significant differences due to the biochar treatment were detected with the feed test result. Higher fertiliser rate had a small effect on increasing fibre but reducing fat content.
This biochar video shows the trial being sown and discusses the trial.
Replicated soil health trial Willow Creek
Alternative soil health treatments across a replicated trial showed promise in building soil health. When compared to an unfertilised control, biologically treated plots showed improved mineral uptake, nitrogen use efficiency, pH and soil health indicators over a one-year period. The cost of the minerals added to the treatments were in most cases beneficial as they were taken up by the plants. The additional cost of biochar added to one treatment may have played a role in improving soil moisture and mineral availability and pH. Unfortunately, we did not find any statistical differences in plant biomass or feed value between treatments possibly due to the season and the method of analyses. A full copy of the report can be found here
5 Soil Health Case Studies
This project aims to provide a better regional understanding of the impact of the alternative and chemical fertilisers on soil moisture holding capacity, growing season length, soil acidity and other soil health parameters such as microbial properties (mainly bacteria and fungi), organic C and pasture production. The methods are used:
• Five paired case study sites on farmer properties measuring soil health (paired means one site has a soil health or chemical treatment and the other a control). The treatments here have been established for a minimum of five years. It is important to note that the paired site is either a different paddock on the same farm or a different farm (next door). All paddocks are adjacent to their comparison. Care was taken to choose similar pasture species and soil types, but the grazing management was not the same and soil health treatments also different.
There was a range of grazing strategies and this influenced soil health and plant available water. The soil health was generally better where there were alternative fertilisers, however the soil health was well supported where there was a high grazing pressure and low grazing days. The soil biology was not as good where there was low ground cover and less plant species diversity.
The cation exchange capacity (CEC) was always higher on the biological sites supporting the transfer of nutrients from the soil to the plant. Denitrification was higher on high chemical N input sites. The pH of the soil was better in biological side irrespective of liming treatment
The report highlights the importance of grazing management, ground cover, and mix of pasture species in conjunction with biological fertilisers to support soil health. The final report needs a few small final edits pending feedback from the case study farmers and can be found here