Sister! This photo of you is too overbearing! You can't take pictures of this plant! ? If it is a newly planted seedling this spring, this situation is very common! If the top is pruned during planting, the top will inevitably dry up after water loss during seedling survival (or after planting, water management is not in place), and the red rosewood will be this color after water loss! If there is no pruning, then another possibility of this situation is that the root system is not well taken when digging seedlings. This phenomenon mostly occurs individually or locally. If the above two situations are excluded, it is caused by disease, but the disease is completely observable. First of all, if it is a disease, there are bound to be obvious symptoms and signs. The specific situation should be as follows: at first, punctate lesions appeared, which gradually expanded into prototype or ellipse, and finally expanded to the whole plant. Later, black or reddish-brown robes were formed on the surface of the lesions. Diseases often spread from a single plant or part, and are not tightly confined to the branches. To sum up, you can judge why the red rosewood you planted has this phenomenon by combining the actual situation of the planting site and the performance of the seedlings.