Cultivating Weeds in Australia

Agricultural greenhouse gas emissions can be curbed by decreasing fuel use by field equipment. The largest contribution to reducing emissions associated with farming is made by the reduction of tillage operations which are made primarily to control weeds. By substituting herbicides for tillage, dramatic reductions in fuel use and emissions occur because one herbicide application substitutes for multiple tillage trips. Tillage equipment is also heavier than herbicide sprayers and needs more energy to pull steel implements through the soil. A row crop cultivator requires four times more diesel fuel per acre than an herbicide sprayer. A recent study in Australia calculated the effects on greenhouse gas emissions…..

“In a wheat fallow system in semi-arid subtropical Queensland, Australia, practicing zero tillage reduced fossil fuel emissions from machinery operation by 2.2 million g CO₂/ha over 33 years or 67 kg CO₂/ha/year (four to five tillage operations with a chisel plough to 10 cm during fallow each year were replaced by one herbicide spray).”

Authors: Ortiz-Monasterio, I., et al.
Affiliation: CIMMYT, Mexico
Title: Greenhouse Gas Mitigation in the Main Cereal Systems: Rice, Wheat and Maize
Source: Climate Change and Crop Production. CAB International 2010.