Leylandi

Leylandii will rob the soil of nutrients. As it is an old tree, the surrounding soil will now be poor so it could be on the way out.

Merlot

Thank you for replying. Do you know if the colour change on the trunk is a sign of that please.

How long ago was it topped? Leylandii hedges seem to survive topping without any ill effects but stand alone trees often die after topping.

Any change of colour in the trunk could mean the health of the tree is compromised. Have the branches shed their foliage?

Merlot

It was topped 3 years ago. When I say topped it was reduced to a flat top with about 4 feet of greenery. It looks perfectly round and flat on top. Sounds odd but it works with the branches. I saw the shape of the trees in the streets of an arab country and I thought, I like them, typical of me then went for it and hubby obliged with the chain saw.

I can accept what you say entirely but I was wondering if there was a disease about. Thanks.

Some years ago we moved house and took over our garden width of Leyandii.
The trees were towering at about 15' and a mess so we had a gardener come in and take the trees down to about 6'. He said he doubted the trees would survice.
I trimmed the trees twice a year continued to feed with horse manure and years later when we moved they looked beautiful.