$ummerWeed Tool: predicting the profitability of summer weed control timing
Summer fallow weed control is widely recognised as being of high value to modern cropping systems. However, decisions around prioritising timing across large programs and diverse weed populations and soils can still be challenging. $ummer Weed Tool is a mobile application that estimates the impact of summer weed control timing on yield and soil nitrogen availability for specified weed and soil conditions.
Based on grower and advisor feedback the app now provides estimates of yield impact, $ value impact, nitrogen impact, N $ value impact and total cost:benefit. A delay of 5-50 days can be selected to determine the likely effect of weed populations of various densities on these outputs relative to immediate control.
The user needs to enter location, soil type (chosen from a list of five), weed type (shallow and deep-rooted), weed density (per m2) and expected wheat value. Including current $ cost of N fertiliser and/or weed control allows financial returns to be calculated.
The app uses an offline database of APSIM runs based on 100 years of climatic conditions to determine the likely impact and includes a probability of achieving at least a 0.2 t/ha yield benefit, 10 kg/ha N benefit and $20/ha value benefit.
The outputs have been tested against a number of field trials in WA, VIC and SA. Additional trials have been run in the 2023-24 summer in NSW and VIC. These trials have demonstrated that the APSIM database used has a good correspondence with measured impacts of full, delayed or no weed control on soil water and soil N at sowing.
This mobile app is available for both Android and IOS devices. It will inform grower and adviser decisions on priorities for control timing for different summer weed populations, based on the likely soil specific impacts on available soil N and water limited yield.
Edwards, E., Ouzman, J., Oliver, Y., & Llewellyn, R. (2024). $ummerWeed Tool: predicting the profitability of summer weed control timing. Proceedings of the 23rd Australasian Weeds Conference Brisbane August 2024., pg168. https://acrobat.adobe.com/id/urn:aaid:sc:AP:24e14be0-0ebf-450d-8433-5b3c7fd07a45?viewer!megaVerb=group-discover
The $ummer weed tool was developed by CSIRO through the support of the GRDC projects CSP2201-005RTX; CSP1911-005RMX; DAW00257 and contributions from CSIRO, WA DPIRD and the University of Adelaide. We acknowledge SquareV for the development of the App; and Birchip Cropping Group, Air EP, Mallee Sustainable Farming and the CSIRO Boorowa Agricultural Research Station and Waite Farming Systems team for running trials.