Natural and Management-Related Variation in Cypress Domes

Fifteen cypress domes located within an extensively managed slash pine plantation were characterized according to the presence and nature of ditches and berms. Mean water depth and hydroperiod for the year 1978-79 were generally greater in the domes without these alterations. Cypress importance values were significantly higher in the unaltered, wet domes whereas hardwood importance values and shrub density were higher in the altered, drier domes. The abundance of grasses and sedges in the domes was more closely correlated with the amount of light reaching the dome floor than with the degree of wetness. Acid-extractable phosphorus, iron, and aluminum concentrations in the dome soils were positively correlated with mean water depth. Carbon concentration in the dome soil was positively correlated with hardwood importance value. Cypress tree growth rates increased significantly following ditching in four domes. This was probably the result of increased soil aeration and increased nutrient inputs from ditch inflow. Cypress growth rates in other altered and unaltered domes were not significantly different before and after intensive forest management of the study site. Although dome alterations sometimes increased cypress tree growth, the associated changes in hydrological conditions, vegetation composition, and soil parameters may inhibit cypress regeneration. FOREST SCI. 29:627--640. ADDITIONAL