They get well over 50/60 feet tall over time, but actually, they don't cause trouble with roads and foundations even at a mature size - in London, you often see one of these (lower branches removed) in a front garden that's no bigger than 10 feet wide by 5 feet deep, and despite the tree being taller than the house, no problems are experienced with foundations or the like.

However, removing the roots of a mature, large specimen is likely to cause upheaval to any road surface nearby, so if you must remove it, best done as soon as possible. Equally, the branches on it are very likely to overhang the road and the walkway there in short order, and as you know, this tree is not pleasant to brush past - it stabs you as you do. On the other hand, like many conifers, this tree does not regrow from old wood, so it is possible to chop it down to ground level and leave the roots in place, which wouldn't cause any disruption at all.

Not sure how easy it would be to dig it up with roots intact and move elsewhere - it might be possible, especially if its been in situ less than 2 years, but likely not without wrecking the grass verge, though that's easily remedied afterwards. You could even cut and lift the grass in small turves, stack them, take the tree and roots out, level off and relay the ones you've cut out.

Thankyou Bamboo, you have confirmed all my thoughts so I think I will fell it now and replace it with a Magnolia I want to move from another part of the garden.I w ill try and remove some roots so as to give space for the new plant to develop.
Thanks again.

I hate to say this, but that space isn't big enough for a Magnolia either - by 'space' I mean the gap between the hedge and the road. Magnolia stellata is small enough it would be okay for up to 5 years probably, but even stellata gets large over time, and those roots most definitely could be a problem for the roadway...

Thank you for asking the question Ianplant. I do not know if there is a branch of your local council who can reassure the owner of the land that the tree will not affect his path. I have been debating whether the Monkey Puzzle tree I have was too big for my garden but Bamboo has answered that and I can safely leave it where it is. I will need to remove the lower branches to let other plants have the space they need. Bamboo when can I cut off the lower branches, should it be now? It is a similar size to the one in Ianplant's photo.

You should really wait a bit longer if its the same as the one pictured - it has 5 well developed tiers of branches, but the sixth is only just developing, and its best to wait until its got 6 full tiers, preferably 7. That said, I removed the lower branches on one a while back when it had almost 6 full tiers, but only two from one side, where they were in the way. I removed the remainder of the lower tier as the tree got taller, and it was fine.

Thank you Bamboo. I appreciate the advice given and as it is not causing any problem at the moment I will allow it to grow some more before I trim off those lower branches. Is it best to cut it back at any particular time of year?

No, it doesn't matter when you do it, they don't bleed copiously or anything like that.

Thank you Bamboo. OH has now been forgiven for buying me a birthday present which I planted very reluctantly because I felt it was far too big for our garden.