Gong sun zhui
Castanopsis tonkinensis
Family: Fagaceae
What it is like
A medium or large tree. It grows 30-35 m tall. The trunk is 50-90 cm across. The leaf stalk is 1-2 cm long. The leaf blade is sword shaped and 6-13 cm long by 1.5-4 cm wide. It is deep green above and green with reddish brown scale like layer underneath. The base is narrow and wedge shaped. The tip is heart shaped or with a short tip. There are 9-13 veins each side of the main vein. The female flowering stalk is about 20 cm long. The cup is oval. It is 2-3 cm across. The fruit is a nut. There is one nut per cup. It is 1 cm high.
There are about 120 Castanopsis species. Many have edible nuts.
Where it is found
A tropical plant. It grows below 1500-1600 m altitude. In southern China it grows up to 2000 m altitude.
Countries/locations it is found in
Asia, China, Indochina, Laos, SE Asia, Vietnam
How it is used for food
The seed contains edible starch.
Edible parts
Seeds, nuts
How it is grown
Its other names
Local names
Ca oi bac bo