Soil variability plays a significant role in crop performance, especially in dry conditions, where spatial variability of soil texture can show the moisture shortage effect on plant stand variability across the field. Generally, soil is not uniform and immense spatial soil texture variability can be noticed across fields (see the June 12, 2006, ICM article (pages 169-171), What's the yield effect of uneven corn heights?). Soil texture is a key factor in influencing soil's water-holding capacity. Coarse-textured soils have a lower moisture-holding capacity due to high porosity and ability to drain excess water quicker than fine-textured soils.
Available at: http://works.bepress.com/mark_hanna/144/