To assess amelioration of subsoil acidity using a range of tillage methods for incorporating surface applied lime into acidic subsoils and the impacts of tillage and lime on crop productivity.

• Soil pH results after liming and tillage treatments were applied was found to be quite variable and more sampling needs to be done before pH results can be quoted. Soil loosening indicates that only the deep tillage techniques were likely to incorporate lime into the deeper 20-30 cm acidic layer.
• This trial highlights the importance of measuring subsoil pH levels and applying sufficient rates of lime to prevent and correct subsoil acidification. Where tillage treatments are used to incorporate lime it is important to understand to what depth lime will be incorporated and which subsoil layers need correction. It is intended to monitor this trial for the next few years to further assess the benefits of correcting subsoil acidification. Yield response to lime incorporation can increase over time as the untreated soil continues to acidify further and as lime has more opportunity to react and neutralize the acidity that is present.