Posted: 08/07/2014 at 17:58
I grew a wildlife hedge consisting of hawthorn, elder and hazel with wild rose and honeysuckle growing through it - fantastic for wildlife.
I think you could take the Leylandii out from August onwards, that way even very late nests will have fledged.
When we took a similar hedge out we were unaware that it had provided hibernation cover for hedgehogs - we've since replaced the dry shade with more undergrowth and log piles as well as hedgehog houses.
Just thought I'd mention it.