Western Australia
August 18, 2014

A new webpage for WA grain growers and advisors is providing valuable 

indications of plant available water versus growing season rainfall at this critical stage of the crop growing season.

Titled ‘Probes and Prophets’, it is available at precisionag and also contains comprehensive crop reports that include: 

• Probabilities of reaching/exceeding yield potential and incidence of frost and heat shock
• Availability of soil nitrogen (N)
• Water and N stress levels
• Projected crop performance with no added rain or fertiliser
• A three month rainfall outlook from the National Climate Centre.

The webpage has been developed as part of a GRDC western Regional Cropping Solutions Networks (RCSN) project using data from soil water capacitance probes and Yield Prophet® models set up at 12 sites across the State.

RCSN project advisors Frank D’Emden, of Precision Agronomics Australia, and Craig Topham, of Agrarian Management in Geraldton, are frequently updating and posting progress reports from each site as the season unfolds.

These reports provide an up-to-date indication of how crops are performing on common soil types and characteristics in all GRDC cropping regions of the State.

The webpage hub contains information about interpreting the soil moisture data and Yield Prophet® information for each site.

Full soil moisture probe datasets, showing variations at 10cm depth increments, rainfall, temperature and humidity can also be viewed by entering the username: RCSN and password: grdc (both case sensitive) into the Outpost Central login portal at the bottom of the webpage.

Timely decision support

By running comparative Yield Prophet® models and soil water probes simultaneously on representative soil types across the WA grainbelt, the RCSN project aims to provide growers and advisors with timely and comprehensive local information about plant available water and N levels.

The project is a step towards new reporting formats and improved WA crop yield predictions based on actual up-to-date soil moisture measurements, site-specific weather data and comprehensive industry-developed modelling systems.

Crop progress around the State

A mid-season report for this RCSN project highlighted that N fertiliser ‘top-ups’ in coming weeks could have variable yield benefits – depending on location.

Frank says potential benefits from top-up N ranged across the 12 Yield Prophet® sites from nil (where soil moisture was marginal) to more than 0.5 tonnes per hectare (where soil moisture was reasonable).

He says individual fertiliser decisions should be based on close assessments of subsoil moisture levels and take into account: low June rainfall in many areas; high 2013 yields and stubble loads; marginal soil N levels; and a decile 5 (average) rainfall outlook to the end of September.

Have your say

Frank and Craig are seeking feedback from grower, advisor and industry users of the new ‘Probes and Prophets’ webpage.

In particular, they would like to know which parts of the Yield Prophet® reports that users would like to see in a ‘dashboard’ style layout.

See ‘more information’ below for their contact details.

Useful resources:

RCSN project ‘Probes and Prophets’ webpage: http://precisionag.com.au/
services/moisture-probes-project

GRDC Ground Cover Water Use Efficiency Supplement: www.grdc.com.au
/GCS82

GRDC Water Use Efficiency Western Fact sheet: www.grdc.com.au/GRDC-FS-WaterUseEfficiencySouthWest

GRDC Hot Topic: Water Use Efficiency and tools for growers: http://www.grdc.com.au/WUE

Yield Prophet® website: www.yieldprophet.com.au

MyCrop & Yield Constraint Calculator: www.agric.wa.gov.au/mycrop

MySoil: www.agric.wa.gov.au/mysoil

SoilMapp: http://www.csiro.au/soilmapp

Website: http://www.grdc.com.au

Published: August 18, 2014