Firstly, tree leaves full of green bumps and then leaves shrink. What is treatment?
Bumps on Leaves
Certified GKH Gardening Expert
I'm not sure on the variety of tree that you are referencing.
Bumps on leaves could be harmless leaf galls or something more serious such as insects or fungus disease.
Leaf galls are common and usually cause not issues.
Leaf curl or insects can usually be treated and managed.
Here are some articles with more information.