Q.Nellie Stevens holly and frost bite on new growth.
Should I trim the blac, dead new browth from the sudden freeze or let the tree and bushes do what they do naturally. Before the sudden frost, the 4 trees and bushes were very healthy and had bloomed their white flowers.

You can trim any dead and damaged branches now.
Also the bottom branches often began to drag on the ground and these can be pruned any time of the year.
For regular pruning--if the plant is 10 years old or younger, prune it in the early spring.
Mature Nellie Stevens Hollies should be pruned in late fall or early spring.