The Summer Weed Tool empowers Australian grains farmers to quantify the benefits of fallow weed control. Users select from a range of locations in southern Australia, and provide estimates of current plant available water, soil type, weed density and weed emergence date to generate a report on the potential benefits of weed control now or at up to 50 days in the future.
Predicting the future
Quantifying the potential benefit of fallow weed control requires estimating the effect of weeds on future crop growth, The $ummerWeedTool app does this simulating weed growth through the summer and then a subsequent wheat crop through the next growing season, using the APSIM crop model. This model is effectively an industry standard and is in use in other tools, such as Yield Prophet. As it is not possible to know the future weather over that time scale the model is run for every season type that has been experienced over the last 100 years. This allows a typical result to be generated together with a probability of achieving particular outcomes. The app is designed to work even in the absence of a mobile internet connection.
The potential yield benefit is calculated using only the impact of weeds on stored soil moisture (i.e. it assumes full rate nitrogen fertiliser applied in all cases), but the app also calculates the impact on soil nitrogen and potential saving in matching nitrogen application to soil nitrogen availability.
Summer fallow weed control
- Australian grain growers have adapted to climate change by conserving more summer soil water and seeding earlier – often before autumn rains.
- Summer weed control has become critical to conserving stored soil water.
- Australian growers now spend $689M p.a. controlling fallow weeds.
- It is difficult to determine the likely value of fallow weed control which can benefit both soil water and nitrogen availability.
- Fallow weeds still cost $259M in yield loss p.a.
Scenario: assume you are standing in the paddock today. You have weeds.
Using the app you can determine your expected yield gain and nitrogen saved from managing weeds now, together with the probability of achieving a threshold yield and N gain.
You can compare these with estimates for delayed weed control up to 50 days from now.
If you provide estimates of grain value, nitrogen cost and weed control cost, the app will provide $ benefit of control now vs later.
Now available on Google Play and Apple Apps
Further Reading:
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.