Reducing Dependence on Nitrogen Fertiliser

Reducing Dependence on Nitrogen Fertiliser.

Peter Burton
24th September 2009


Uncertainty still surrounds farm incomes over the next twelve months however all the signs are presently positive, so the worst possible scenarios of 6 months ago appear to be dissipating.

Fertiliser is expenditure able to be reduced or eliminated, with many farmers taking one of the options in autumn. Farms with a good history of nutrient inputs are able to withstand periods of no nutrient input without markedly jeopardising pasture production. How long depends on the factors of soil storage capacity, total soil nutrient, soil condition, and production demands.

Slow growth periods over winter are almost inevitably followed by exceptional strong growth periods. During winter there is significant activity taking place within the soil. Plants are renewing roots; fungi, bacteria, earthworms, and other beneficial organisms are providing the basis for rapid plant growth as soil temperatures increase beyond 10ºC.

The excellent growth conditions particularly in August has provided pasture covers on the Eco-Logic Soil Improvement monitor properties that are close to or in excess of feed budget targets with milk solid production in several cases at record levels.

The months of October and November are the ideal time for the application of nutrient that ensures maximum animal production over late spring, summer, and early autumn. CalciZest, Eco-Logic Soil Improvement’s unique soil improver containing 21% calcium helps ensure maximum clover growth throughout this period.

Typically phosphorus, sulphur, and potassium are included with CalciZest to ensure maximum clover and animal production throughout the major production period. Clovers are able to provide increased feed as soils approach and surpass 20ºC.

Clover provides a number of other benefits when dominant over the warmer growing months. Strong clover growth helps shelter the ground reducing moisture loss. It is markedly higher in calcium and more digestible with animals able to eat more kilo-grams in a given period resulting in higher milk solid production, or increased weight gain in rapidly growing animals.

Clovers grown using CalciZest as the base are little affected by either clover flea or weevil. Pests have the function of eliminating weakened plants. Strong plants are left virtually untouched able to fix all the nitrogen necessary for 16.0 tonne plus of pasture dry matter in a twelve month period without the need for fertiliser nitrogen.

CalciZest also significantly improves physical soil structures and it was noticeable last summer when repining cages after cutting that even when soils were at their driest they were still soft.

Observation and feel are greatly underrated skills in farming. Inevitably the best farmers are the best observers and know that there is a strong correlation between the best performing pastures on the property and the feel underfoot.

Well-structured soil encourages plant roots to delve deeper utilising moisture and nutrient from as far down as 0.8m. Well-anchored pasture plants are less prone to pulling with the need for pasture renovation eliminated on long-term ESI properties.

Walking the farm, particularly the far end of paddocks on a regular basis provides a wealth of information. Decision-making is easier and the best decisions are more readily reached when preceded by careful and regular observation.