Q.Should I Cut Back Willow Whips?
Last autumn we planted some willow whips in a damp area. They were given to us through Mersey Forest scheme and are about five feet in height. Most are showing good growth. A few are showing no signs of life. Three of them are developing a few leaves right down at the base but above that the whip looks dead. My question is, should I cut back the whips to give the growth more chance?

Certified GKH Gardening Expert
I would, only, cut dead growth. Any pruning to living growth will need to be done during dormancy. Here are some articles that will help you to care for these trees:
https://www.gardeningknowhow.com/ornamental/trees/willow/grow-a-willow-tree.htm
https://www.gardeningknowhow.com/ornamental/trees/willow/how-to-prune-willow-trees.htm