Thanks for your reply regarding the wee leaf munchers.
After you identified them as the one of the Tent Caterpillar tribe I searched on line for what was available for these. Doesn't appear to be any problems handling these of this tribe and seem very selective of the leaves that they munch.
Quite different from the Chenille Processionnaire that we encountered in France. I can recall the shrieks coming from some young French when we had our tent pitched under a Pine with one the silk hammocks dangling above us.
Again on the mainland of France we came across Pine trees with traps strapped to the trunks of Pines I guess to funnel the creatures into some fluid. These guys seem to move in joined up chains to another area of the forest.
Also I have read that Oak trees can be attacked.