What shrub is this?

Hi all, I recently moved house, it had a jungle for a garden with a lot of overgrown shrubs.  I cut everything back to wood to gain control... one such thick woody stump has started to sprout quite succulent shoots with thick leaves lately all over, it was fine last week but now has started to show signs of something sinister.  The main shoots are turning black and withered at the very top of shoot and there is black juice on some lower leaves..and the next shoot buds look dark around the edges.  I can’t see any bugs on it apart from the odd cuckoo spit on one or two leaves.
Firstly...can you help identify the shrub? (See pic of shoot that was easily knocked off) and pic of log with shoots


secondly...what do you think is wrong with it and can I do anything to prevent it?


thank you