Learning's from assessments of reduced till and controlled traffic farming. Jim Page, Agricultural Economist, DEEDI, Nambour.

Min till and controlled traffic reduce power required & fuel consumption by % - (Jeff Tullberg) It reduces the power required to overcome rolling resistance (the process of compacting wheel tracks) by approx 20% of total power use it eliminates the power required to cultivate the compaction created by wheels- approx 20% It eliminates the need for follow- up cultivations to shatter compacted clods from the compacted wheel tracks.

Minimum tillage and controlled traffic pays. Change in machinery costs- $71,000 initial cost for tower & to equip two tractors. Reduction in machine operating costs and associated labour (eg for planting) for a 80 ha small cop farm: –Reduction in variable machinery costs (Fuel, Oil, Repairs & Maintenance, tractor, implement & labour: $235/ ha/ year & $18,826 for the farm, giving a 40.8% return on an average investment of $46,150. –Reduction in variable & fixed cost of machinery (including interest and depreciation & labour) $202/ ha & $6,173 total annual saving for the farm, giving a 35% return on average investment of $46,150 –Carbon emissions reduced by around 32 t/ 80ha/ yr,

Investment analysis of min til, CTF with 5% yield gain on 80 ha farm Assumed total initial investment of $220, 000 for GPS guidance, machinery modification, contingencies and on-farm works. Net Present Value $264,251 (discount rate 7%) Benefit cost ratio of $2.28:$1(discount rate 7%) Internal rate of return (IRR) 39%

Learnings: Need to take a comprehensive view of investment situation- looking at min till, controlled traffic or purchase of GPS guidance separately would probably result in three decisions not to invest. Adding them together builds confidence in outcomes such as a yield gain that make the combined proposition a worthwhile investment

Min till, CTF with GPS guidance are a starting point, what follows is critical: Everyone who implements these practices & those who switch from flood to more efficient irrigation systems are struck by the improvements to the soil resource. These are early steps toward a farming system that focuses more on the physical, chemical and biological resource of soils rather than a focus solely on crop performance.

The emerging production system of controlled traffic, min till, soil focussed production. Min tillGPS guidanceControlled traffic Green harvest, trash blanket, break crop Change to OHLP or trickle irrigation Precision farming, reduced pesticide use Soil focussed production system Save some fuelSave some more fuel Significantly reduce compaction Increased harvest costs More precise water application Precision farming reduces damage to soil structure and soil bio- activity. Symbiotic relations between soil organisms & plant roots accomplished- fert rates can be cut. Slightly reduce compaction More accurate placement of beds Cut fuel consumption and power required by 40+% Reduce irrigation requirement Reduce water logging Soil beneficials replace chemical treatment for fungal, nematode etc issues Most soil pathogens now controlled by beneficial microbes. Minor yield gains, perhaps more plants/ ha Soils start to recover structure & bio activity Lower weed control & pesticide costs Lower water tables The need to cultivate has largely disappeared. Probably lower yields but profit maintained because of reduced fert and pesticide inputs Plants access larger volume of soil, water & nutrients More bio-mas for developing bio- activity in soils. Bio- activity of soils improves significantly Application rates of most inputs reduced- hi tech application equip't now used Longer rotations, reduced average planting costs. Serious carbon emissions gains Potential to develop symbiotic relations between soil organisms & plant roots. Costs are falling, yields are being maintained. Area of cane harvested increases as area required to produce plant cane is reduced Serious carbon emission & sequestration gains Carbon sequestration gains Stronger healthier plants extend life of varieties, allows increased emphasis on yield instead of pest & disease resistance. THE PAYOFF Very smallAgain limitedSignificantProbably marginalProbably marginal at best There are some serious pay-offs here somewhere The Holy grail of farming

Conclusion: The economic analysis indicates that the gains associated with min till CTF justify significant upfront investment and effort. Understanding how reduced compaction, soil disturbance, water logging etc allow soils to be more productive will encourage & support more rapid adoption. There are many other practice changes that will enhance the condition & performance of soils. The emerging package of practices will help in the response to higher energy, fertilizer, pesticide & water costs as well as any future carbon taxes.