Why not?

You can train almost any tree I imagine. If you can turn one into bonsai specimens then it should respond well to training.

We have a lot of Hazel in the hedges around here and although they get mashed by flail cutters every year they keep growing back and if left will fruit, so I think you could safely train yours up trellis. The only doubtful area is how to prune for best fruiting, I'm not sure whether they are tip bearing or spur bearing, but there's bound to be a book in your local library which will give pruning advice.

thanks for the info! i'll get training..

Keep us posted as to how you get along. I'd love to have hazel but don't feel I have the room, so trellis might be a viable option if something else goes.

i will do.. although i must confess the tree is one of those hazelnut trees from seeds of italy which have truffle spores, so it's those i am more interested in... I think I'm in for a long wait though!