Huge Lilac - help needed!

Hi everyone,

When I moved into my house 15 months ago there was a massive lilac bush/tree in the centre of the garden which I loved. It was tall then but now it is getting ridiculously so, about 15 ft high or more, and unfortunately is leaning quite heavily to one side. I'm so worried it will fall and die and I know I need to cut it back but I don't even know where to start! Can someone tell me how low I can cut it as I need to stabilise it and would love to not kill it. It just has so many branches at the bottom and I'm not very experienced

 

If it was in my garden I think I would remove about half the branches right at the bottom and reduce the height to about 6ft on the others. Then fork in some blood fish and bone round the base.
Lilacs are pretty tough and will take regular fairly hard pruning.

 

One thing to remember is that lilacs flower on older wood and if you cut it right down you will lose the next years flowers.

 

Thanks Nigel, that's good to know!

 

Blimey 68 is very impressive! Thanks for the advice, I'm always worried to do things like this but if other people have done it then it should be fine and you guys know what you're talking about. The tree is a silver birch and is in my neighbours garden, along with a massive willow. They both desperately need pollarding but he's planning on moving soon so doesn't want to pay for it We're going to cut off the overhanging branches to open our side up more (he's fine with this) and hopefully that will help the lilac when it grows back. Here's hoping the new neighbours decide to cut the trees back!

 

It didn't flower last year or this year so it can only help it by cutting it back I guess