An investigation of baldcypress stands associated with Caddo Lake was undertaken as part of an evaluation of a proposed project to increase storage capacity of the lake. Existing stands either were impacted by or established in response to an increase in water levels that occurred seventy years ago. Examination of stand characteristics and hydrologic records indicated a predictable response to water fluctuation patterns that provided a basis for assessment of various proposed project alternatives. Baldcypress is able to persist in the face of hydrologic regime changes, but growth, reproduction, and survival are directly related to the frequency of substrate exposure. Relationships defined in this study may be useful in identifying impact thresholds and optimal water management strategies for other baldcypress stands.