For maximum profitability, a cotton producer must attempt to control the quality of the crop while minimizing costs and maximizing yield. One strategy that may help to accomplish this difficult task is adoption site-specific management practices. Site-specific management allows a producer to apply crop inputs on an individual-needs basis, as opposed to a single-field average rate. This is accomplished by dividing the field into management zones, which receive prescribed levels of crop inputs. The first step in defining management zones is determination of the inherent soil and crop spatial variability present in the field. The objective of this research was measurement of the natural variability present in cotton fiber yield and quality parameters in relation to the underlying soil spatial variability.