Cropping Inputs, Diary Number 2
[Transcript of Cropping Inputs, Diary Number 2]
Hi, welcome to this month’s Cropping Inputs Diary. Last month we discussed Independent Comprehensive Soil Tests, as a first step towards deciding cropping inputs. We talked about the importance of balanced soils that encourage our diverse and active life in the soil.
With these key points in mind, I want to focus now on deciding the inputs of the cropping program. When considering any soil and cropping input, thoughts should always be given to what impact the product will have on soil life and balance. Not all chemicals are detrimental, but some are. Particularly insecticides and fungicides and a few herbicides. Balanced soils will negate the need for these chemicals. Also, some fertilisers or excess inputs of some fertilisers are detrimental to soils. Ignoring this is the prime reason why for the very poor fertiliser use efficiency in Agriculture today and obviously leading to increased costs. Well most soils are inherently unbalanced chemically, lack of consideration of cropping inputs is adding to the problem. By addressing the balance of nutrients as shown by this leaking barrel illustration will optimize fertiliser use efficiency.
Research by Sardi has shown only 3% to 30% of phosphorus applied is utilised by the plant in the year of application. The rest being locked up or leeched or both. Nitrogen use efficiency, particularly with the rates of Urea being used in cropping situations at present is very poor. Importantly Urea in access is toxic to soil life and soil physical structure. This picture by CSIRO researches shows the toxicity of banned urea at 5 cm to replants, and the same research shows the leaching of this nitrate and oxygen down the soil profile, taking calcium and other nutrients with it. Some good work here done by Dr. Ash Martin shows the effect of microbiology and nutrient availability when using Urea as apposed to ammonium sulphate, a much more soil friendly fertiliser.
Fertilisers such as potassium chloride with 50% chloride is also a poor choice affecting water uptake by the plant. It seems in Agriculture today that MPK fertiliser are all that are considered, well ignoring all the other mineral nutrients required in the soil. Soils that are balanced chemically are now alive with a diversity of microbe activity have a tremendous ability to mineralize nutrients into an available form to the plant. In the next presentation we will go back to the soil tests and specifically talk about the inputs for that particular soil to bring about the desired outcomes discussed here without compromising our soils while still maximising productivity and quality.