Kaman walnut (Kaman cevizi) is a local walnut variety grown within the boundaries of Kaman district in Kırşehir province, located in Türkiye’s Central Anatolia Region, distinguished by its physical and biological characteristics. It has been registered as a “designation of origin” under the Industrial Property Law No. 6769 and has been protected under a geographical indication since December 9, 2020. The registration was carried out by the Kaman District Directorate of Agriculture and Forestry.
Distinctive Features
Kaman walnut is recognized for its light brown shell color and light yellow inner kernel. The fruits are oval or round, with thin shells (1–1.4 mm) that separate easily from the kernel. The average fruit weight ranges from 11–16 grams, with the kernel weighing 6–8 grams, resulting in a kernel ratio of 48–54%. The fruit size is medium to large, free of foreign tastes or odors. The shell has low to moderate roughness. The trees are distinguished by their spreading crown structure, providing consistent annual yields. Lateral branch productivity is around 60–70%.
Kaman walnut trees develop strong taproots, reaching depths of 3–5 meters. The trunk is smooth and silver-colored when young, turning gray-black with longitudinal cracks as it ages. Shoots are hairless, glossy olive green, or brownish. The trees exhibit protogyny (female flowers blooming first). Fruit buds form on one-year-old branches, producing fruits in clusters. The flowering period is April 1–16, and the harvest period is September 20–October 10.
Ecological Conditions
Kaman district’s continental climate and fertile plateau soils provide an ideal environment for walnut cultivation. Sufficient chilling hours (approximately 1,200–1,500 hours) are met in winter, while hot and dry summer conditions help control fungal and bacterial diseases that could reduce walnut quality. The optimal temperature range during the growing season is 25–35 °C. Excessive heat can cause sunburn on the green husk and darkening of the kernel, making harvest timing critical.
Production Method
Kaman walnut production is carried out using on-site grafting. Before establishing an orchard, soil analyses are conducted. If suitable, planting sites are marked at 10x10 meter intervals, and seeds are sown. During the first growing season, irrigation, fertilization, and training are applied. In the second season, just before bud break in April, whip grafting is performed, or in August, dormant bud grafting is applied to the rootstocks. The main trunk is trained upright, and crowning is done at 1–1.5 meters. Lateral branches are ensured to have wide angles and proper positioning. Harvest occurs when the inner membrane turns brown and the green husk splits. Fruits are separated from the outer husk manually or mechanically and dried without direct sunlight exposure. Drying is complete when the shelled walnut reaches a moisture level of 8%.
Inspection and Protection
The protection of Kaman walnut as a geographically indicated product is overseen by the Kaman District Directorate of Agriculture and Forestry. The inspection body consists of experts appointed by the Kaman Municipality, Kaman Chamber of Agriculture, and Kaman Chamber of Commerce and Industry. Inspections are conducted at least once a year routinely, with additional inspections in response to complaints or as needed. Inspection criteria include shell color, thickness, roughness, fruit weight, kernel ratio, shape, taste, and verification of the production location through records. Product packaging must include the “Kaman Walnut” designation, the registered logo, and the designation of origin emblem.
Cultural Context
Kaman walnut is not only an agricultural product but also an integral part of the region’s culture. The “Walnut Culture and Art Festival,” held annually since 1991, reflects the social and cultural significance of this product for the people of Kaman.
