Any thicker layer of mulch may cause problems. Raking the mulch will give it a new look. Yes, many trees and shrubs can be pruned during spring. During early spring, some plants may bleed, but this causes no permanent damage. My ornamental grasses turned brown over the winter.
Many ornamental grasses turn color during the winter.
The brown leaves and stems should be cut down to the ground. New leaves and stems will develop from the plant base.