Illustrated Compendium of Materia Medica (Vol. 34)

Blue Oak original: "青岡樹" (Qinggangshu). Cyclobalanopsis glauca, also known as the Ring-cupped Oak.

The Materia Medica for Relief of Famine original: "救荒本草" (Jiuhuang Bencao). A 15th-century handbook by Zhu Xiao listing plants edible during times of starvation. does not record the specific regions where the Blue Oak is produced, but today it is found everywhere. Among these trees, those that grow large and bear acorn cups acorn cup (橡斗): The woody, cup-shaped base that holds the oak nut. are known as Oriental Oaks original: "橡櫟" (Xiangli). Likely referring to Quercus variabilis or Quercus serrata., while those that are smaller and do not bear acorn cups are called Blue Oaks.

The branches, leaves, twigs, and trunks of the Blue Oak are all similar to those of the Oriental Oak, but the leaf color is a notably deep bluish-green and it produces few flowers. Furthermore, it has a bitter taste, a balanced nature, and is non-toxic. To prepare it for eating, gather the tender leaves and blanch blanch (煠): To briefly boil or scald in water to remove bitterness. them until thoroughly cooked. Soak them in water until they turn a pale yellow color, then change the water and wash them clean. They may then be seasoned with oil and salt for consumption.

Note: The Blue Oak grows mixed with the Oriental Oak on hills and mounds; they are essentially of the same category, though this type lacks flowers and fruit. Upon the tips of its branches, it often forms silk balls which are as fine as cherry filaments but quite hard. The local silk of Guizhou is actually produced from the silkworm cocoons found on this tree; its benefits are widespread indeed. Just as the mulberry has mulberries and the oak has acorns, neither are suitable for the common domesticated silkworm—it is the same principle. The author is explaining that wild silk moths feed on these oaks, unlike the common silkworm which requires mulberry leaves.

I have now appended the Records of the Oak hereafter. Yao doctors Traditional healers from the Yao ethnic group in Southern China. in Hunan call this the White Chestnut Ball or the Dwarf Chestnut, because its silk balls become round and white by autumn, resembling a shelled chestnut. These are used to treat bloody dysentery and white diarrhea white diarrhea (白瀉): A traditional medical category for pale, watery stools, often associated with "cold" or "dampness" in the digestive system..