I've just felled four 30ft leylandii, 10 inch diameter at base. A
long rope tied high up and looped over a handy branch of the next tree
allowed them to be lowered gently to the ground after cutting through
with an axe. I didn't wnat to cut them down in stages as I am going
to use the timber. It is very strong and the heart wood is very
durable. It's a cross between Monteray Pine and Alaska Yellow Cedar,
which has a couple of natural chemicals that are toxic to fungi. In
New Zealand and Australia leylandii are grown comercially for the
timber. The smaller pieces do make excellent firewood, even the
leaves having a very high calorific value sa there is so much resin.
One day we'll be planting them everywhere as a fuel and timber crop.