We had a massive Leylandii hedge in our last garden. It was 180ft long and 15ft tall, not to mention about 6ft wide. (We didn't plant it, the previous owners did, the fools) We had to use a huge scaffolding tower on wheels to trim it. Eventually we got a 'tree-surgeon' team in to halve its height. We burned the cuttings on a massive bonfire in our half-acre garden. (Leylandii burns well as there seems to be oil in the leaves)

The thing is, this blinking ugly, monstrous hedge never seemed to have any attraction for wildlife. No birds ever made their nests in it. No insects went near it. It never gave any type of fruit for birds during the winter. Nothing would grow beneath it as it rendered the soil bone dry like dust. Totally sterile and useless thing.

Compare that to a gorgeous 'mixed hedge' found at field edges, established for centuries. Birds' nests, insects, small mammals, fruit, (hips for example) and mayflowers if there's hawthorn. Wild flowers a-plenty using the shelter. Far better.