To test Yield Prophet for 2005.

• Yield Prophet® in 2005 had many new features and capabilities and was delivered to 338 paddocks that were subscribed Australia-wide. From 5 April to 1 December, 6813 reports of various types were generated by subscribers, with most around time of top-dressing.
• Final simulated yields for wheat crops, using appropriately measured soil characterisation and initial soil data, fitted observed yields comparable to previous seasons (R2=0.74, 67% of simulated yields within 0.5 t/ha of observed, 98 % within 1.0 t/ha).
• Yield Prophet simulates yield more accurately than it does grain protein content.
• However, overall accuracy for all subscribed crops was lower due to expansion into new regions with less soil characterisation data available.