Frozen Sap

It's spring and the trees are sucking up water through their roots and up the trunk in to the branches to feed the buds.
A late afternoon pruning followed by the freezing air gives an indication of just how much water trees take in, and why the loss of trees from our habitat is contributing to the problems of flooding, and water levels.
The cumulative effect of the rapid loss of hedgerows and trees is greatly misunderstood.