CONCORD, N.H. — The state is evaluating whether a 16-acre patch of old red spruce trees on the side of Mount Sunapee is a pristine enough patch of land to require legal protection that could derail a ski area’s contentious and long-debated proposal to expand over state park lands. In a report delivered to the state’s Department of Resources and Economic Development and provided to The Associated Press, the state’s Natural Heritage Bureau said it confirmed the existence of the stand of mostly red spruce trees, some of which were over 170 years old.