Funnily enough I just had a similar problem.. Had an acer tree a big ish one with a large shrub beneath it that looked. Mess, I had to cut it down to the bass and the roots were tangled with the trees just a little, I had to saw and hack at the direct roots coming from the bush and took about an hour to remove, I then dug over the surface area and added some compost and plant food and replanted with new plants and topped with gravel.. I did a blog about it too :)

I would cut the shrubs down to ground level. The shock will probably kill them, saving you the hassle of root-removal.

I agree, I only dug mine out to replant :) if you can, then avoid it :)

A word of caution re replanting the area though - cherry roots are not far under the surface, and there are lots of them, and they do not like disturbance. Which is why any other planting you want around a cherry tree is best done at the same time...

Thanks for all your advice,think I will cut them right down and see what happens,if it looks too messy Ill cover with bark chippings.I dont mind if i cant plant something else would just prefer it without these big shrubs .