The Saururaceae family consists of perennial herbs with a generally pungent odor. Their leaves are simple and have stipules. The flowers are small, arranged in spikes, and densely packed. They lack a perianth. The fruit is a capsule or berry, and the seeds are spherical with abundant endosperm. There are 4 genera and 6 species in North America and Asia. Two genera are found in Japan.
This article provides a comprehensive, field guide-style introduction to plants belonging to the Saururaceae family.
The basic information is based on the Kanagawa Prefecture Flora Survey Association (2018). Photos are replaced as better ones become available. While the identification is done by the author, please note that misidentifications may be corrected without notice.
No.0082 Saururus chinensis
This is a perennial herb. Its rhizomes are thick and spread horizontally. The stems grow to a height of 50-100 cm and are hairless except for the inflorescence. The leaves are 5-15 cm long and 3-8 cm wide, with entire margins and usually five prominent veins. Leaves near the inflorescence turn nearly half white during the flowering season. The inflorescence is 5-15 cm long, initially drooping but later becoming erect, and is covered with curly hairs. The flowers are small and lack petals. It flowers from June to August. It is distributed in Honshu, Shikoku, Kyushu, the Ryukyu Islands, Korea, China, and Southeast Asia. It grows in moist places such as swamps and wetlands.
No. 0083 Houttuynia cordata
This is a perennial herb. It has white rhizomes that spread horizontally. The stems are 30-50 cm tall, hairless except for the stipules, and usually tinged with dark purple. The leaves are petiolate, dull dark green, 4-10 cm long and 3-7 cm wide, with a sharply pointed tip. The inflorescences grow opposite the leaves. The flowers are arranged in spikes 1-3 cm long, with four white bracts at the base. It flowers from May to June. It is distributed in Honshu, Shikoku, Kyushu, and the Ryukyu Islands; as well as China, the Himalayas, and Southeast Asia. It grows well even in the shade and is commonly found.
No.0083.1 Houttuynia cordata f. plena
Yaedokudami is a variety of Houttuynia cordata in which the bracteoles within the inflorescence become larger, resembling double-flowered blossoms.
References
Kanagawa Prefecture Flora Survey Association. 2018. Kanagawa Prefecture Flora 2018 (Electronic Edition). Kanagawa Prefecture Flora Survey Association, Odawara. 1803pp. ISBN: 9784991053726
