Lateral Variations in Hydric Soil Indicators Near a Swale in an Urban Park

Hydric soils have unique properties as a result of developing in anaerobic conditions, such as when submerged in water. A swale is a small runoff channel, either natural or human-made. The swale in this study, in an urban nature center, conveys water only at times of significant run off. Standard methods and practices from the U.S. Department of Agriculture were used for field identification of hydric soils within the swale. Soils were sampled and tested in and along the swale to find hydric soil indicators, including soil color and odor. Gray colors and sulfurous odor are indicators of hydric soil; soil color was evaluated by the Munsell Color Guide. Sampling began in the middle of the swale and then proceeded laterally outward. At the time of sampling, there was not running water in the swale; however, the soil was still visibly wet. The presence of hydric soil indicators is expected to decrease laterally outward from the swale center. Soil cores indicate natural soil horizons (undisturbed soils) in the swale with some evidence of human disturbance away from the swale. Preliminary results indicate that slope is an important factor in the relationship between distance from swale and presence of hydric soil indicators.