Hi everyone

So I have a major dilemma, last year Me and my partner cleared an area in our back garden( around 20x10ft) that was heavily densed by brambles and other forestry shrubs. We cleared it by hand as it was so thick and is also on a steep bank.

Since then the brambles have grown back, so we bought super weed killer from our local farm store and it had two doses lasts year (very strong doses I might add). So left it over winter and there coming up again! I've sprayed AGAIN but I don't hold out much hope.

The roots are so established underneath the soil I think it needs rotivating. Is this the right plan of action? There are some biggish stones under the soil too. I did think about doing it by hand but the trees behind our patch have blooming roots that come through onto our soil?!?!?

PLEASE HELP! Any advice would be appreciated greatly!!!!!