Old-growth forests once dominated New York. Now they're among the rarest habitats. New old-growth forests can't be created, but the large standing dead trees, downed logs, and gaps in the canopy created by storms are a great starting point for restoring old-growth characteristics to your woodlot.
In the long term, the only way to keep invasive plants at bay is to make sure you have healthy native plants growing. If you’ve just controlled invasive plants in an area, planting some natives from a nursery can help them get a jumpstart on resprouting invasives.