Hello, why is my michelia alba tree's leave keeps turing black and the branch has white stuff on it?

Question:Hello, why is my michelia alba tree's leave keeps turing black and the branch has white stuff on it? it was all healthy with tons of big green leaves but all of the sudden with no reason, it starts to turn black from the tip of the leave and then all fall off. I did'nt over water it. if anyone of you knows the answer, please share before it's too late! thanks guys !

Answers:
Is the tree planted in the ground or in a pot? (here in USDA zone 8 they are container plants)

The white fuzz makes me think of either fungus (mold) or possibly a type of aphid, basically sucking the life from the branches, you can get lady bugs who are predatory for the aphids, or chemical insecticides. Below are some other options...

If the tree is in a pot, occasionally salts from fertilizers (either that you have used, or used by the nursery/store it came from) can build up in the soil, you may want to "flush" the soil with clean pure water to remove the salts.

Also, even without over watering if the soil is not draining well, fungus and or bacteria can grow in the soil, check for funny smelling soil, or poor root growth, if so repot with new better draining soil immediately.

If the leaves turn yellow first and new leaves never firm up, you may not be giving it enough light...