Zouma Gexianmi

Zouma Gexianmi

Zouma Gexianmi is a protected geographical indication product.

Zouma Gexianmi is an agricultural geographical indication product.

　　Zouma Gexianmi has been known to people for over 1,500 years. According to *Compendium of Materia Medica*, “Gexianmi grows on stones in caves along the streams of Huguang (now Zouma Town, Hefeng County, Hubei Province). When heavy rain washes open the cave entrances, the grains flow out with the water. Locals collect them; when first gathered, they resemble small, fresh wood ear mushrooms, purple-green in color. When mixed with vinegar, they become plump and green and are edible. Locally called ‘Kaixian Cai,’ when dried they are known as ‘Tianxian Mi.’ During the Jin Dynasty, Ge Hong, who was hiding here and suffering from food scarcity, foraged and consumed them, hence the name ‘Gexianmi.’” This is the legend passed down through generations by the Tujia ancestors: during his journey through the southern mountains, Jin Dynasty’s Ge Hong (an Eastern Jin alchemist, physician, and Taoist ethicist) fell ill near Zouma. Stricken by famine, he foraged and ate these grains, miraculously recovering from his illness. Later, when Ge Hong went to the capital, he presented them to the emperor. The frail crown prince recovered his health after eating them, and the empress, who had suffered from incurable night blindness despite seeking medical help, was also cured. Deeply grateful, the emperor renamed “Tianxian Mi” to “Gexianmi.”

　　Zouma Gexianmi is a type of freshwater wild algae plant and a famous specialty of Zouma Town, Hefeng County, Hubei Province, with a long history of export. It is a multicellular filamentous blue-green algae, belonging to the same phylum (Cyanophyta), class (Cyanophyceae), order (Nostocales), and family (Nostocaceae) as nostoc and hair moss. Nostoc is one of the most widely distributed blue-green algae known, found in various water bodies, soils, river estuaries, and even polar regions. However, the distribution of Gexianmi (scientific name: *Nostoc sphaeroides*) is extremely rare. Its main distribution in China is in Zouma Town, Hefeng County, Hubei Province, with reports of small amounts also found in Africa. Gexianmi grows in underdeveloped mountainous water areas, is naturally pollution-free, and is an authentic green food. It is highly nutritious, classified as a high-protein multi-functional nutritional food, a rare delicacy at banquets, and is considered a unique treasure of China and a rare gem of the world.

　　Gexianmi is not a grain. It is called “mi” (rice) because its shape resembles rice grains. When harvested and dried, the grains are round, and when cooked, they are slightly larger than rice grains. It attaches to sandy stones or damp soil in rice fields, shallow pools, lakes, and streams, forming spherical gelatinous structures that resemble wood ear mushrooms, hence it is also called “water wood ear” or “field wood ear.” It has no roots, stems, or leaves and floats in water, thus also known as “Tianxian Mi” or “Tianxian Cai.” It consists of many cells connected in bead-like colonies, with a blue-green color, round and translucent grains that can rival pearls. When cooked as a vegetable dish, it tastes extremely delicious and is regarded as a rare delicacy, hence the beautiful name “Pearl Vegetable.” The Qing Dynasty historical records list it as an imperial tribute and delicacy. In the autobiography *My First Half of Life* by the last emperor Puyi, there is a dish called “Duck Cubes with Stir-Fried Gexianmi.”

　　Zouma Gexianmi won the gold award at the China Agricultural Expo (Wuhan) in 1998, obtained green food certification and Ministry of Agriculture geographical indication certification for agricultural products in 2008, and received trademark registration approved by the National Trademark Office in 2010.

　　In addition to these products, Enshi Autonomous Prefecture also offers ethnic handicrafts such as new types of candle breeding products and Gem Flower Chopsticks, as well as local specialties like Badong persimmons.

　　Geographical Scope

　　Zouma Gexianmi is produced in 20 villages within Zouma Town, Hefeng County, Hubei Province: Qianjin Village, Wangjiabao Village, Gucheng Village, Yanghe Village, Liqiao Village, Baiguo Village, Jinlong Village, Guancang Village, Liujiaya Village, Huaqiao Village, Shengzi Village, Suoping Village, Gangjiawan Village, Jiuling Village, Beizhen Village, Jingang Village, Dadian Village, Meiping Village, Hongtu Village, and Jiudong Village.

　　Zouma Town is located in the southwestern part of Hefeng County, Hubei Province. It borders the Hupingshan Tourist Area of Hunan Province to the east and the Zhangjiajie Scenic Area to the south. It is 600 kilometers from Wuhan and Changsha, and 270 kilometers from Yichang Port. Its geographical coordinates are between 109°8′–110°3′ east longitude and 29°39′–30°9′ north latitude. With an average elevation of 920 meters and a relative elevation difference of 1,086 meters, it is known as the “Window of Southwestern Hubei.” The total production area is 1,050 hectares, with a total yield of 10 tons.

　　Natural Ecological Environment and Humanistic Historical Factors

　　(1) Soil and Topography: Zouma Town has a variety of soil types, including yellow soil, yellow-brown soil, limestone soil, and paddy soil, covering a total area of 73,858 mu. The soil in the town is generally neutral to slightly alkaline, commonly nitrogen-deficient, severely zinc-deficient, but rich in organic matter. The terrain is broadly characterized by higher elevations in the northwest and lower in the southeast, with significant elevation differences, towering mountains, undulating peaks, crisscrossing streams, and deeply dissected surfaces, exhibiting the geographical features of hills and mountainous areas.

　　(2) Climate: Zouma Town has a subtropical continental non-monsoon humid climate, featuring three distinct geographical forms—high mountains, mid-high mountains, and low mountains—each with unique climatic conditions. The seasons are distinct, with cold winters and hot summers, early springs and cool autumns, abundant rainfall, concurrent rain and heat, long frost-free periods, and pronounced vertical climate variations. The annual average temperature is 12.2°C, with an accumulated annual temperature of 3,691°C, annual sunshine duration of 1,342 hours, a sunshine rate of 30%, and a frost-free period of 225 days.

　　(3) Hydrology: Zouma Town has a vast territory with crisscrossing rivers and streams, including the Jiangping River basin. The area receives abundant rainfall, with an average annual precipitation of 1,934 mm.

　　There are no large chemical plants in Zouma Town, and there is no emission of “three wastes” or air pollution, nor is there a history of heavy metal contamination. According to monitoring by environmental authorities, the surface water in Zouma Town meets the national Class II water quality standards of the *Surface Water Environmental Quality Standards*. The water is clear, colorless, odorless, transparent, with a pH value between 4.5 and 7. Relevant indicators such as arsenic ≤0.05, cadmium ≤0.005, and lead ≤0.05 comply with both Chinese and World Health Organization drinking water quality standards.

　　(4) Humanistic History: According to *Compendium of Materia Medica*, “Gexianmi grows on stones in caves along the streams of Huguang (now Zouma Town, Hefeng County, Hubei Province). When heavy rain washes open the cave entrances, the grains flow out with the water. Locals collect them; when first gathered, they resemble small, fresh wood ear mushrooms, purple-green in color. When mixed with vinegar, they become plump and green and are edible. Locally called ‘Tianxian Cai’; when dried they are known as ‘Tianxian Mi.’ During the Jin Dynasty, Ge Hong (an Eastern Jin alchemist, physician, and Taoist ethicist) traveling through Zouma fell ill, and out of necessity foraged and ate them, miraculously recovering from his illness. Later, when Ge Hong went to the capital, he presented them to the emperor. The frail crown prince recovered his health after eating them, and the empress, who had suffered from incurable night blindness despite seeking medical help, was also cured. Deeply grateful, the emperor renamed ‘Tianxian Mi’ to ‘Gexianmi.’”

　　According to a report by Academician Li Shanghao from the Institute of Hydrobiology, Chinese Academy of Sciences, after inspecting Zouma: “Gexianmi has minimal production globally—even in seven acres of land in Africa—but in Zouma, Hefeng County, Hubei Province, there is a production area of ten thousand acres, with remarkably high yields, which is truly rare in the world.”

　　This shows that the cultivation and utilization history of our county has deep roots. The Hefeng County Party Committee and County Government attach great importance to the production of “Hefeng Zouma Gexianmi,” consistently regarding it as the leading industry of Zouma Town. Policies such as *Opinions on Accelerating the Development of Hefeng Zouma Gexianmi* have been issued, continuously expanding the protection and utilization efforts of Zouma Gexianmi, broadening sales channels, and making Gexianmi production a key industry driving the agricultural and rural economic development of Zouma Town, as well as a primary means of income growth for farmers. In 2002, the National Science and Technology Ministry and Hubei Provincial Science and Technology Department listed the *Research on Artificial Propagation Technology and Product Development of Gexianmi* in Zouma as a major project under the Hubei Provincial Major Science and Technology Development Program.

　　Production Technical Requirements

　　(1) Origin Selection and Special Content Regulations: The base for Hefeng Zouma Gexianmi is located in 20 villages in Zouma Town: Qianjin Village, Wangjiabao Village, Gucheng Village, Yanghe Village, Liqiao Village, Baiguo Village, Jinlong Village, Guancang Village, Liujiaya Village, Huaqiao Village, Shengzi Village, Suoping Village, Gangjiawan Village, Jiuling Village, Beizhen Village, Jingang Village, Dadian Village, Meiping Village, Hongtu Village, and Jiudong Village. The environmental quality of the production site must comply with the requirements of the *Technical Regulations for the Production Environment of Green Food Origins* (NY/T391-2000).

　　(2) Variety Selection: Zouma Gexianmi.

　　(3) Production Process Management: The production process of Hefeng Zouma Gexianmi must follow the *Hefeng Zouma Gexianmi Production Technical Procedures*. To ensure the quality characteristics of Hefeng Zouma Gexianmi, particular attention must be paid to the following aspects: ① Fertilization Management: Increase organic fertilizer application in winter, mainly using well-rotted farmyard manure, cake fertilizer, and pen manure. Fertilization should be combined with intertillage and deep plowing. ② Pest and Disease Control: Adhere to the principle of “prevention first, integrated control.” Use agricultural, physical, and biological control methods. For example, install one frequency-vibrating insect-killing lamp per 50 acres to eliminate moths and reduce pest damage.

　　(4) Product Harvesting and Post-Harvest Processing Regulations: The harvesting period for Hefeng Zouma Gexianmi is from April to May each year. Harvesting quality: collect when the grains are dark green and bead-shaped. The harvesting environment must ensure about 17 cm of water depth in the paddy fields. Harvesting method: manual harvesting, to be carried out on sunny days, using bamboo tools. After harvesting, transport promptly to processing facilities that meet green food processing conditions using specialized equipment. Processing personnel must undergo training in Hefeng Zouma Gexianmi production techniques and hold certifications. Upon entering the workshop, raw materials must be manually sorted to remove impurities, then graded according to standards, washed, drained, dried, winnowed, manually rechecked for impurities, and finally graded, packaged, and stored.

　　(5) Production Record Requirements: The entire production process of Hefeng Zouma Gexianmi must establish production record archives that are accurate, clear, neat, and complete. All records must be comprehensively documented and properly preserved for future reference.

　　Product Typical Quality Characteristics and Product Quality Safety Regulations

　　(1) Sensory Characteristics: The finished product is dark green, bead-shaped, with no off-odors and no non-Gexianmi foreign matter. When rehydrated in warm water, it becomes dark green, bead-shaped with a diameter not exceeding 8 mm, crystal-clear, with the unique delicate fragrance of Hefeng Zouma Gexianmi, and the soup is colorless, clear, and bright.

　　(1) Sensory characteristics: The finished product appears as dark green granules, free from any off-odors and must not contain non-Nostoc sphaeroides impurities; when rehydrated in warm water, it forms dark green, spherical beads no larger than 8 mm in diameter, translucent and delicate, with the unique fresh aroma of Hefeng Zouma Nostoc sphaeroides, and the broth is colorless, clear, and bright.

　　(2) Internal quality indicators: 100 grams of dried He Feng Zouma Gexianmi contains ≥24g of protein, ≥8g of vitamin C (mg/kg), ≤10g of ash content, and ≤18g of moisture. Hygiene and pesticide residue levels comply with relevant national standards.

　　(3) Safety requirements: Zouma Gexianmi complies with the "He Feng Zouma Gexianmi" standard DB42/305-2005.

　　Packaging, labeling, and related regulations

　　(1) Grading: Zouma Gexianmi is divided into three grades—Special Grade, First Grade, and Second Grade—according to the local standard "He Feng Zouma Gexianmi."

　　(2) Packaging: This product is packaged in cartons. The net weight of each carton within the same batch must be uniform. It is lined with food-grade plastic bags or aluminum-plastic bags and then packed in graded paper boxes. The labels on sales packaging must comply with GB7718 regulations.

　　(3) Labeling: Users of the mark shall uniformly display the agricultural product geographical indication (the name of He Feng Zouma Gexianmi, the public logo design, and labeling format) on their products or packaging.

　　(4) Storage and transportation: Comply with the "Green Food Storage and Transportation Guidelines" (NY/T1056-2006).