Ask the masters, what tree is this? Spring is green leaves, and summer becomes this color. I look forward to your advice.

You can find pictures on Baidu.

Deciduous tree of Rosaceae, with purplish red leaves all year round, is a famous foliage tree species, which is suitable for solitary and group planting and can set off the background. Purple-leaf plum has purple-gray branches, reddish-brown buds, smooth and hairless leaves, shorter stamens than petals and a single petal. Pink and white flowers look good against purple leaves. Especially the bright purple leaves, among the green leaves, like an unbeaten flower, form a beautiful scenery in the green mountains and green waters.

See Baidu Encyclopedia for details.