Apple tree problem

Hello
I'm new round here but i do have a problem with my 10 year old cox apple tree. Last summer although it cropped pretty well, the end two feet of almost all the twiggy branches wilted. there seemed to be a greyish fur at first which became browner over time and the ends just seemed to die.
this spring the tree generally seems healthy but ther is very little blossom and not much leaf. large lengths of the branches are bare
Any ideas gratefully received
DART

 

sounds like possibly wooly aphids to me

is this similar to the prob....
http://www.crocus.co.uk/pestscards/woollyaphids/