Yachibozu Sedge Tussocks
The fens of the Kushiro Wetlands are dotted with clumps or tussocks of sedge called yachibozu that look almost like long-haired heads sticking up from the ground. As the sedge grows, the old leaves wither and spiky green new growth sprouts on the tops of the tussocks, creating successive layers of sedge leaves that hang down around the sides like hair.
Their startling height is caused by the combination of thick seasonal frost and thin snow cover on the wetlands. During cold winters, the roots of the tussocks are forced upward as the ground freezes. In spring, meltwater erodes the soil around the tussocks, exposing the roots further and making the tussocks appear taller. After about 40 years of ground freeze and erosion, some tussocks can reach 40 to 50 centimeters in height.
The yachibozu tussocks can be found in the Kushiro Wetlands as well as in the nearby Kiritappu Wetlands, which have a similar microclimate.