Hyperspectral sensing of diffuse soil reflectance is emerging as an effective method for rapid determination of soil properties. This project used near infra-red reflectance data gathered from dried, ground soil samples to analyze the treatment effects associated with three long-term tillage experiments (plow-till vs. no-till) maintained by Cornell University in New York State. A traditional analysis of covariance (ANCOVA) for complete block experiments was calculated sequentially for reflectance data from each 1-nm waveband from 420 to 2500 nm, revealing highly significant differences in soil brightness associated with tillage treatments. No-till soils were darker than plowed soils at two of three sites, and also exhibited increased organic matter, decreased pH, and various other differences in chemical properties and aggregate stability. Similarly, ANCOVA analysis of first derivatives of hyperspectral reflectance revealed significant tillage-related differences in adsorption features that were correlated with soil chemical and physical properties. A split-plot harvest treatment (grain vs. silage) had no significant effect on soil reflectance, and also had no significant effect on soil chemical and physical properties. Further investigation is warranted, to evaluate between-site differences and effects of soil type. Hyperspectral sensing of soil reflectance shows promise as a method of evaluating treatment effects in classical agronomic field experiments, although site-to-site variability remains important.