This is a Beech hedge - Mountain hardy species below 7' include Physocarpus spa., Spiraea douglasii, S. 'Snowmound', Rosa rugo… | Beech hedge, Hedges, Screen plants
Copper Beech Hedging – Do you really know what you want?
5 Copper Beech 4-5ft Purple Hedging Trees, Stunning all Year Colour | eBay