Wulong Highland Potatoes

Wulong Highland Potatoes

Wulong Highland Potatoes are a product certified with a Geographical Indication for Agricultural Products.

　　Geographical Scope

　　Wulong County is situated on the southeastern edge of Chongqing, at the junction of the Dalou Mountain fold belt of the Yunnan-Guizhou Plateau and the Wuling Mountain Range, between 107°13′–108°05′ east longitude and 29°02′–29°40′ north latitude. The area is predominantly mountainous, with relative elevations generally ranging between 700–1000 meters. The highest elevation in the county is 2033.3 meters, and the lowest is 160 meters. Wulong Highland Potatoes are produced in the high-altitude mountainous areas above 1200 meters within the territory of Wulong County, Chongqing. These areas include Shiliangzi Village in Xiannvshan Town, east of Xiannvshan Mountain Range and Xiannvshan National Forest Park, as well as Zouma Village and Puban Village in Xiangkou Town, east of Baimashan Mountain Range and Baimashan Nature Reserve. The production area spans 800 hectares, with an annual yield of 18,000 tons.

　　Natural Ecological Environment and Humanistic Historical Factors

　　(1) Soil and Topography: The production area of Wulong Highland Potatoes features limestone strata, with yellow soil as the predominant soil type, mostly rock-derived. The soil pH ranges from 5.5 to 6.5, with an average organic matter content of 2.6–3%. The ecological environment is superior, with good quality soil, agricultural irrigation water, and air, and no industrial “three wastes” pollution.

　　(2) Hydrology: The county has a highly developed water system. The main course of the Wu River flows from east to west across the entire territory, spanning over 80 kilometers. It is joined by twelve tributaries including the Furong River, Daxi River, Muzong River, Changtu River, and Shiliang River, forming the Wu River system within Wulong. In addition to the Wu River, the total volume of water resources in the area is 2.17 billion cubic meters, of which surface runoff accounts for 2.08 billion cubic meters. Agricultural irrigation water in the production area mainly relies on surface runoff or reservoirs, with abundant seasonal water supply. The silt content of agricultural irrigation water is 5–20%,

　　the mineralization level is <1g/L, and the irrigation water temperature can be reasonably adjusted according to the natural characteristics of the county and the growth period of crops, meeting the national quality requirements for farmland irrigation water.

　　(3) Climate: The area has a subtropical monsoon climate, characterized by mild temperatures, abundant rainfall, distinct seasons—spring rains, summer droughts, autumn drizzles, and winter dryness—with frequent cloud cover, limited sunshine, a relatively long frost-free period, and significant vertical climatic differences. The annual average temperature is 10–17°C, annual rainfall is 1094.4 mm, the frost-free period lasts 210–260 days, and the relative humidity of the air is 74–83%.

　　(4) Humanistic and Historical Background: Wulong County is a UNESCO World Natural Heritage site of karst landscapes, with a forest coverage rate of around 40%. The area features attractions such as Xiannvshan National Forest Park, Baimashan Nature Reserve, Furongjiang Scenic Area, Furong Cave, Tiansheng Sanqiao (Three Natural Bridges), and the Tiankeng Difeng (Heavenly Pit Rift). Since the 19th century, there has been a tradition of planting potatoes in high-altitude regions. Large-scale cultivation began in the early 1980s with the introduction of new varieties. Since then, continuous variety updates and quality control measures have led to an expansion in planting area. Due to the vast highland arable land, crop rotation practices, and favorable climate with minimal pests and diseases, the “Wulong Highland Potatoes” produced here possess distinctive qualities—being crispy, tender, sweet, and flavorful. They are suitable for stir-frying, boiling, or making into dried vegetables. Wulong is the first county in Chongqing to promote pollution-free vegetable farming comprehensively. Wulong vegetables have become a major source of supply for Chongqing’s urban markets during the off-season, and they also hold a certain market share in surrounding provinces, cities, and the southeast coast. The high volume of product exports has significantly increased farmers’ incomes. The Wulong County Government has prioritized vegetable farming as a leading agricultural industry, and the Chongqing Municipal Government has listed the Wulong Vegetable Base as a key supply source for ensuring Chongqing’s urban vegetable supply during the off-season.

　　Production Technical Requirements

　　(1) Origin Selection: The production area of Wulong Highland Potatoes is located in the high-altitude mountainous areas above 1200 meters within the territory of Wulong County, Chongqing, specifically Shiliangzi Village in Xiannvshan Town, east of Xiannvshan Mountain Range and Xiannvshan National Forest Park, as well as Zouma Village and Puban Village in Xiangkou Town, east of Baimashan Mountain Range and Baimashan Nature Reserve. The origin quality complies with the “Agricultural Product Safety Quality – Requirements for Pollution-Free Vegetable Production Environment” (GB18407.1-2001).

　　(2) Variety Selection: Disease and pest-resistant potato varieties with good external and internal quality that meet market demand are selected, such as Eshu No. 3.

　　(3) Production Process Management: The production process follows the “Pollution-Free Food Potato Production Technical Regulations” (NY5221-2005).

　　(4) Product Harvesting and Post-Harvest Handling: Potatoes are harvested and supplied to local and Chongqing urban markets in stages based on market conditions after tuber bulking. Fully matured potatoes are harvested for storage, processing, or export to other markets.

　　(5) Production Record Requirements: Field production records are established by growers or base cooperatives and township agricultural service centers, with comprehensive documentation and proper preservation for future reference.

　　Product Typical Quality Characteristics and Quality Safety Standards

　　(1) Product Characteristics of Wulong Highland Potatoes: The tubers are flat-round, with yellowish-white skin. They offer a good taste and a unique aroma, free from rot, off-odors, pests, diseases, or mechanical damage. The tubers typically contain 15% starch, 1.5% sugar, around 2% protein, 1.1% mineral salts, as well as vitamins B and C, providing high nutritional value. They can serve as both a staple food and an excellent vegetable.

　　(2) Safety Requirements for Wulong Highland Potatoes: The products comply with the “Agricultural Product Safety Quality – Safety Requirements for Pollution-Free Vegetables” (GB18406.1-2001).

　　Packaging, Labeling, and Related Standards

　　Wulong Highland Potatoes are classified into four grades—Special Grade, Premium Grade, First Grade, and Second Grade—based on their shape, color, tenderness, and product characteristics after harvest. Special Grade potatoes are transported by refrigerated trucks to ports by export enterprises, and then shipped in refrigerated containers to the southeast coastal region or exported to Southeast Asia. Premium-grade vegetables are quantitatively packaged using fresh-keeping trays and cling film, labeled with vegetable quality and safety identifiers, and stored in layered plastic boxes indicating product name, net weight, origin, harvest date, shockproof information, etc. These are delivered to contracted supermarkets by fresh vegetable processing companies using fast packaging and transportation. First-grade products are transported quickly in bulk or bags to Chongqing urban and surrounding wholesale markets. Second-grade products are directly purchased by county-based processing enterprises for further processing.

　　Wulong alpine potatoes are graded into four levels—superior, first-class, second-class, and third-class—after harvest based on product shape, color, tenderness, and product characteristics. Superior-grade potatoes are transported by refrigerated trucks to ports by export enterprises, then shipped in refrigerated containers to southeastern coastal areas or exported to Southeast Asia. First-class vegetables are quantitatively packaged on fresh trays with cling film, labeled with vegetable quality and safety marks, and stored in layers in plastic boxes marked with product name, net weight, origin, picking date, shockproofing, etc. They are quickly loaded and delivered by fresh produce processing enterprises to contracted supermarkets. Second-class potatoes are transported in bulk or bags to wholesale markets in Chongqing’s main urban area and surrounding regions. Third-class potatoes are directly purchased and processed by processing enterprises within the county.