Medicinal Value of the Bark, Kernel and Leaves of the Oak Tree (Huli)
The oak tree Huli (Quercus dentata) of the Fagaceae is a deciduous tree up to 25 m tall, growing mostly on sunny mountain slopes below 2700 m elevation; it is distributed in most regions of China. Its bark is serrated, and its fruit is ovate or broadly ovate, about 1.2-1.5 cm in diameter. The bark, kernel and leaves of Huli all enter medicine.Huli bark, also called Hupi, Humu Pi, Chilong Pi and Hubai Pi, has the actions of detoxifying and reducing swelling, astringing the intestines, and stopping bleeding. It chiefly treats swollen, painful sores and abscesses, ulcers that do not heal, scrofula, hemorrhoids, dysentery, and bleeding from intestinal wind.Ancient doctors mostly used Hupi to treat various festering sores. For example, Sun Simiao, the King of Medicine, recorded in his Qianjin Yaofang (Essential Prescriptions Worth a Thousand Gold) that to treat gu fu ju (bone-deep abscess, i.e. suppurative osteomyelitis), burn Hupi into powder and take one square-cun spoonful (about one teaspoon) with water.Gu fu ju is a serious suppurative disease, mostly caused by Staphylococcus aureus and group B streptococcus infection; if not treated promptly it leads to skin ulceration, forming sinus tracts and invading the bone marrow, hence the name bone-deep abscess. That Hupi can treat this disease shows it has good antibacterial, anti-inflammatory, hemostatic and wound-astringing actions.In the Zhou Hou Fang (Emergency Prescriptions Kept Up One Sleeve) of Ge Hong of the Jin dynasty there is a formula called Chilong Pi Tang (Red Dragon Bark Decoction), made by taking three sheng of Hupi (cut) and one dou of water and boiling down to five sheng. This formula is used to wash the wound; after washing, various plasters are applied externally, to treat various festering sores and breast sores (here breast sores should mean breast ulceration caused by mastitis or breast tumor). This is much like modern hospitals first washing a wound with iodophor before applying medicine, showing that ancient doctors had already discovered that Huli bark, whether taken internally or applied externally, has good antibacterial, anti-inflammatory, wound-astringing and edge-closing effects.The Shenghui Fang also records treating small heat sores on the nipple after childbirth (acute mastitis) that discharge yellow water when scratched: take three sheng of Huli bark, one dou of water, boil to five sheng, and wash the breast and wound twice daily. This is also a method of using Huli bark decoction for surgical disinfection. The Puji Fang also records applying Huli bark to the affected area to treat chronic dry ringworm that forms crusts, discharges yellow water when scratched, and itches whenever it is cloudy or rainy; this disease may be intractable eczema and is hard to treat. The Yixin Fang records treating women vaginal odor (vaginitis): take one sheng of Hupi, two liang of Gancao (Licorice), three liang of Danggui (Angelica), boil in one dou of water to three sheng, strain, and wash the vaginal opening.The Zhou Hou Fang also records treatment of lower-body sores: boil Hupi and Jupi (zelkova bark), with the decoction as thick as maltose, and use it for daozhi (guided insertion). It is hard to verify today exactly what kind of treatment this guided insertion was; it may have been inserted into the anus like some of today suppositories, though my understanding may be wrong.These show that this herb was commonly used in the past to treat various skin and surgical diseases.Hupi can also be taken internally to treat enlarged lymph nodes. The Shenghui Fang records taking three ge of Hubai Pi (cut), using one ge each time, with one large cup of water, decocting to five-tenths, straining and taking warm. After taking it, the person should vomit foul matter; if after walking ten li they have not vomited, decoct another ge and take it. One ge in the Song dynasty was about 100 ml. The enlarged lymph nodes here should be infection-caused. In addition, Hupi decocted and taken internally also treats diarrhea and bacterial dysentery. Modern internal use of Huli bark is usually 5-10 g.The kernel of Huli also enters medicine; its main action is astringing the intestines and stopping diarrhea, chiefly treating diarrhea and dysentery. The Bencao Gangmu (Compendium of Materia Medica) records that Huli kernel can be steamed, boiled and made into powder to astringe the intestines and stop dysentery. The Xiandai Shiyong Zhongyao (Modern Practical Materia Medica) also records that Huli kernel treats childhood rickets. In some places it is used to treat lacquer sore, a dermatitis caused by paint allergy.The leaves of Huli have the actions of stopping bleeding and promoting diuresis/relieving stranguria; they chiefly treat vomiting of blood, epistaxis, blood in stool, hemorrhoidal bleeding, bloody dysentery, and painful, difficult urination. The Shenghui Fang records: To treat severe epistaxis with bleeding from mouth and ears that will not stop, pound Huli leaves and squeeze out the juice; take one small cup each time. The ancients used it this way, showing that Huli leaves have a very good hemostatic effect.The Shengji Zonglu records that dried Huli leaves pounded into powder are taken at two qian coins with one cup of water, boiled five to seven times, and taken warm with the dregs, to treat vomiting of blood. The Bencao Yanyi records that Huli leaves (slightly roasted) and stir-fried Huaihua (Sophora flower) in a 2:1 ratio, made into a powder, treat intestinal wind (blood in stool) and bleeding hemorrhoids.Huli leaves also have a fairly good diuretic action. Both the Puji Fang and the Shenghui Fang record formulas using single-herb Huli leaves to treat difficult and painful urination caused by lin disease; the difficult and painful urination here should be caused by urethritis.In summary, the bark, leaves and kernel of Huli all have fairly good broad-spectrum antibacterial and anti-inflammatory actions, and also a certain hemostatic effect, making it an ideal medicine for surgical diseases.