This investment will provide research aimed at quantifying soil and crop effects on Crop Lower Limits (CLL - the amount of water remining in the soil after a crop has extracted all the water available to it) separately to inform new and more robust approaches to both measurement and prediction of CLL. This work will improve our understanding of the relationship between the field methodology and laboratory measurements as well as providing a means to capture differences between crop types and variety-specific characteristics. Better understanding and quantification of the effects of soil constraints on root water extraction responses of different crops can assist with evaluation of soil amelioration techniques as well as informing management decisions such as whether to sow, timing of sowing (and associated crop type and variety choice) and the input level of resources such as nitrogen fertiliser.