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Towada-Hachimantai NP, Aomori
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The rare gomashijimi butterfly lives here; across Tōhoku, records are limited to Aomori and Iwate. Its caterpillar first eats flowers, then ants carry it into a nest, where it feeds on their larvae.
Peat deposits at Tashirodaira preserve 2 distinct ash layers: one from nearby Towada volcano, the other from faraway Baitoushan (Paektu). These thin seams give geologists eruption markers inside the wetland.
Peat at Tashirodaira preserves a continuous record from the end of the last Ice Age, about 15,000 years ago. Aomori Prefectural History describes the layers as an archive of changing vegetation beneath your feet.
Aomori Prefectural History connects Hakkōda’s name with the wetland’s scattered ponds, called kami-no-ta, or “fields of the gods.” Dense sedges in a pond can resemble tiny cultivated paddies.
At about 560 m—low for Hakkōda—Tashirodaira holds a habitat mosaic: sphagnum-rich raised bog, swamp-grass intermediate marsh, and lower marshes dominated by reeds and sedges.
Aomori Prefectural History lists sundew among Hakkōda’s bog plants. Its sparkling, sticky leaf hairs catch insects, helping this tiny carnivorous plant gather nutrients in nutrient-poor peatland.
Some pools here hold a surprising pair: Ezo-no-hitsujigusa, a water lily, and hime-mizuni, an aquatic fern. Aomori Prefectural History notes that pool depth helps shape which plants can grow in each one.
The marsh’s color changes with the season: white, cottony watasuge and pink tokiso orchids appear in June–July; summer brings golden kinko-ka, followed by small white umebachisō blooms in August.
Tashirodaira’s plant community—not just one tree or flower—was designated a Natural Monument on November 7, 1968. The designation recognizes the wetland’s distinctive assemblage of peatland plants.
