I have a Quercus garryana that was overrun by 30' Himalayan blackberries vines and bent over, it is now 15-20' tall and still bent over, but I just cleared out more blackberries and found it had suckered at the base, some nice straight suckers, one 6' tall, so maybe I can just let them grow and eventually cut down the bent tree, but I don't know if I should trim off all the suckers but the tall one. Also should I leave the bent tree until the sucker is larger so the tree can continue to store energy in the roots, or would the sucker do better with the big tree cut down?

The oak is in the foreground close to the plastic, the tree is on the left and can be seen bending to the right, and the suckers are just to the right of it.