Ants/Insects on Ilex Meserveae Hedging

I have a row of Ilex Meserveae (Blue Prince), the ends of each hedging plant have fresh buds wanting to sprout out but they have gone brown and the leaves have shrivelled. Some because of insects/ants and some because of windburn.
QUESTIONS
What do I do? Do I cut it to the nearest bud? or do I cut down to the branch and wait for years? Or do I just spray with bug killer and hope they sprout again?
If the advice is cut it, how do I stop this in the future?

 

I would suggest that the the problem is lack of water. How long have you had them? Wind burn will sort itself out as the plants mature. Spraying never solves anything. Hollies are tough and sometimes leaves show brown patches caused by holly leaf miners. Ants can't possibly damage your holly

 

Cutthe brown bit off, and spray with a bug killer. You won't be able to stop windburn - but checking regularly when the new buds form, should mean you spot any pests e.g. aphids, which the ants farm, early and deal with them. Either Bug Gun, or soapy water, should do the trick.

 

Shrubs and trees need a lot of water in their first year after planting. That may be the cause of the buds not opening and leaves shrivelling. You can trim of the brown leaves if you like and give as much water as you can. Then wait and see if they recover.