Osmund is a perennial herbaceous plant belonging to the family Ophioglossaceae. Its tender, curled, and unexpanded leaves are considered a delicacy for consumption.
China has a long history of eating osmund. As far back as the late Shang and early Zhou Dynasty, there were records of people picking and eating osmund, including the records in Erya (an early Chinese lexicon possibly assembled in the Qin (221 BC–207 BC) or early Han (206 BC–220 AD) Dynasty that is considered a classic work of Chinese literature and is sometimes ranked with the Five Classics in importance and influence. It is a compilation of words found in texts from the Zhou Dynasty (1046–256 BC) and is organized into 19 categories). Sheng Nong’s Herbal Classic recorded osmund as one of the Chinese herd medicines with the functions of activating blood circulation, clearing away heat and dampness and nourishing liver for improving eyesight.
Tongdong County is one of the main production areas of osmund in China. The plants typically grow to about 1 meter in height, with short, thick, upright rhizomes that form a stout, cylindrical main axis, topped with clusters of leaves. Tongdao osmund features fresh, tender, and glossy stems and leaves, with plump and smooth leaf blades. When used as a vegetable, it has a crisp texture with low fiber content, a delicious taste, and is rich in nutrients. Every 100 grams of fresh stems and leaves contains 3.8 grams of protein, 0.5 grams of fat, 9 grams of carbohydrates, 200 milligrams of calcium, and 70 milligrams of phosphorus. It also contains a significant amount of ascorbic acid. In its dried form, every 100 grams contains 21.8 to 37.6 grams of protein, 4.0 to 9.5 grams of carbohydrates, and trace amounts of cyanogenic compounds, as well as arginine, hydroxyarginine, and hydroxybutyric acid. The protein content of osmund is comparable to that of Malan (another type of vegetable) and is three times that of cabbage. Its levels of carbohydrates, inorganic salts, and ascorbic acid are higher than those found in Malan and other leafy greens. The various nutritional components of osmund rank it among the top vegetables, significantly impacting metabolism and various physiological functions in the body.
Tongdao osmund is known for its functions in clearing heat, promoting diuresis, invigorating blood circulation, and improving eyesight. It can be used to treat conditions such as edema, jaundice, malaria, palpitations, irregular menstruation, nocturnal emissions, and ulcers, making it a highly sought-after mountain delicacy. Young leaves are processed into dried products, which not only become exquisite dishes for banquets and ideal gifts but are also exported to Japan and Southeast Asia, with sales increasing year by year.
(Translated by Yang Hong)
