I think it very mean of him to cut it so severely & not leave any foliage to fill the gap. What I would do asap is buy a length of trellis & attach it to the top of your fence. Then when that's in place attach some of that nice green windbreak material to the trellis thus filling it all in. I don't think it would look too bad if you buy the right kind. He can't very well cut that down ( I'm presuming it's your fence). If you cut the top of the C off instead, it probably would bush out again eventually, but in the end he could still cut it off again. He probably doesn't like plants. Sorry you have difficult neighbours. It makes such a difference when one has someone next door that you really get along with. I am very lucky.

Fixing anything to the fence, Feverfew, is very tricky as the tree branches are lying against it. Your suggestion is a good one but I’ll give it some thought as it wouldn’t be me fixing it up. Husband isn’t worried about it so doesn’t want to do anything. I’d rather the neighbours, who are noisy and have frequent smoky BBQs, moved elsewhere!

Sorry, Arbuthnot, for some reason I thought you were a man. Now getting hubbies to do things that they aren't really bothered about is tricky. I hope you can come up with a solution. Good luck.