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The criterion for wetland hydrology is based on the presence of saturated conditions for a continuous period during the growing season. Changes have been proposed to extend the growing season to 365 days for locations in the Atlantic and Gulf coastal plain. A computer simulation study was conducted to examine the effect of changes in the growing season at Plymouth, NC. Results showed that the proposed change in the growing season, without changing other elements of the hydrologic criterion, will substantially reduce the saturation (or high water table) requirements for wetland hydrology. A site that would have a water table within 30 cm of the surface for a continuous period of 14 days in 50% of the years during a 365 day growing season at Plymouth, NC would satisfy the same criterion for a continuous period of only 7 days during the standard 28F growing season. Lateral impacts of a drainage ditch on adjacent wetlands, as determined by current methods, would be reduced by an average of 42%. Increasing the growing season to 365 days would substantially reduce saturation requirements at the wet end of the wetland spectrum (12.5% of the growing season) which is typically required for restoration of prior converted wetlands in mitigation projects. More research is needed to develop a scientifically rigorous.