Throughout the 2011-12 season, BCG is conducting an exciting research project in the Wimmera Mallee. It aims to increase farm efficiency and productivity by means of an assessment of new spray technology.
This project ‘the use of weed sensors for variable rate herbicide application across the Wimmera Mallee’ aims to determine the situations and weed population densities in which the use of weed sensing equipment can be economically justified; develop key strategies and practices that maximise the potential gains from weed sensing technology; increase the awareness of the benefits of weed sensing technology and establish whether this technology has a use beyond summer weed control.
Until recently, weed sensing technology has had limited commercial use in southern Australia. It uses light emitting diodes (LED) to measure the reflectance from the ground. The sensor is able to identify a green plant through the different reflectance it emits and then activates the spray nozzle to apply the herbicide automatically.
Labour shortages, increased summer weed establishment as a result of higher summer rainfall and elevated input costs have generated significant interest in the technology. Weed sensing technology, it is suggested, has the potential to achieve greater farm efficiencies and boost productivity by reducing herbicide use by 60 – 90%, reducing chemical costs by 85% and minimising spray drift. It is better for the environment and allows faster spraying speeds, resulting in rapid coverage. Little independent analysis to validate these claims has been conducted; BCG intends to fill this gap.
Four large-scale replicated trials will be established in paddocks where blanket applications are considered marginal. These trials will ascertain the reduction in herbicide usage and the logistical improvements that could result. Three treatments – blanket application, application by a weed sensing boom (WeedSeeker®) and a combination of WeedSeeker® and blanket application – will be compared.
Two smaller replicated plot trials will be set up during summer and winter. The summer trial will identify optimal spray strategies for controlling different weed species, densities and size to determine when a single WeedSeeker® application or a combination of blanket and WeekSeeker® treatment is necessary. The winter trial will investigate the in-crop application potential of the technology. The weeds targeted in this trial will be common Heliotrope (Heliotropium europaeum), Camel Melon (Citrullus lanatus) and Marshmallow (Malva parviflora).
This project has been supported by the Rural Industries Research and Development Corporation (RIRDC).
