The Uryu Experimental Forest (ca. 25,000ha) was established in 1901. The forest is located in the basin of the Uryu River, a branch of the Ishikari River, and it surrounds Lake Syumarinai, the largest artificial lake in Japan. The climate is characterized by cold temperature (-35 degrees C) and heavy snowfall (200 cm depth or more) in winter. The northern part of the forest is largely dominated by mixed stands of conifer and broadleaved tree species, including pure stands of Quercus crispula, wetland stands of Picea glehnii, and large riparian forests. In the southern part, Picea glehnii stands on serpentine soil are common as well as second-growth broadleaved stands established following large artificial disturbances. The major research topics include cycling of water and materials at various spatial scales, and regeneration of natural forests. Long-term ecological monitoring of many biotic and abiotic subjects is continuously being conducted, and related large-scale field experiments are being introduced. The forest is associated with the Nayoro Tree Breeding Station, which is in charge of studies regarding tree breeding and genetics, nursery practices to produce tree seedlings, and various field experiments.