We planted a Royal Raindrops crab apple in 2015. Last spring the tree bloomed normally and the leaves remained through the fall, falling as usual. Crab apples remained on the branches; we noticed no signs of disease. However; it did not bud at all this spring and appears dead. There are light colored "bumps" on the bark, but we don't know if that is normal. At the base, many root suckers have appeared, which is new. We wonder about disease, soil issues, anything at all that caused this and would prevent a new tree from growing when we replace this one. We've attached 3 photos...the tree, the bark, a cut branch. We would appreciate any help or direction as to how to solve this problem. Thank you.