From your picture, this plant is called Pingpo. Pingpo, an evergreen tree of Sterculiaceae, also known as "Eichhornia crassipes", has long oval leaves; Flowers in early summer, no corolla, pink calyx, panicle; The fruit is divided into four or five sub-fruits, with dark red outside and black finish. Seeds are edible and taste like chestnuts when cooked.
Pingpo is often planted as a garden tree in southern China, and its wood is light and tough, so it can be used to make utensils.