Tamurasou - Tamurasou

A perennial herb of the Asteraceae family. The rhizome is somewhat thick and woody, and the stem is erect and reaches a height of 1.5 meters. The leaves are large and pinnately lobed, thin, and without thorns. From August to November, the stem branches out at the top, and at the end of the branches, large reddish purple flower heads are borne. The flower heads consist of thin neutral tubular flowers and thick bisexual tubular flowers, and the end of the style is divided into two and opens. There are many densely overlapping involucres. The flower bed has scaly bristles. The achene is cylindrical and glabrous. The pappus is not feathery. It resembles thistles, but differs in that the leaves have no thorns, the style branches open, and the pappus is not feathery. It grows in open grasslands and plateaus in mountainous areas, and is distributed from Honshu to Kyushu and the Korean Peninsula. The basic subspecies subsp. coronata is distributed from Siberia to Europe.

[Hiroyuki Koyama]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

キク科の多年草。根茎はやや太い木質で、茎は直立し、高さ1.5メートルに達する。葉は大形で羽状に切れ込み、質が薄く、刺(とげ)はない。8～11月、茎の上部に枝を分け、その先に大きな赤紫色の頭花をつける。頭花は中性の細い管状花と両性の太い管状花からなり、花柱の先は二分して開出する。総包片は多数で密に重なる。花床には鱗片(りんぺん)状の剛毛がある。痩果(そうか)は円柱形で無毛。冠毛は羽毛状にならない。アザミの類に似るが、葉に刺がなく、花柱分枝が開出し、冠毛が羽毛状でないなどの点で異なる。山地の開けた草地や高原に生え、本州から九州、朝鮮半島に分布する。基本亜種subsp. coronataはシベリアからヨーロッパにかけて分布する。

［小山博滋］

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