Iris - Japanese iris

Japanese: アヤメ - あやめ

A perennial plant of the Iridaceae family (APG classification: Iridaceae). The rhizome grows horizontally, is hard, and is covered with brown fibers. The leaves are 30-50 cm long, 5-10 mm wide, arranged alternately in two rows, straddling, and have a thin central vein. The flower stalk is 30-60 cm tall and unbranched. The flowers are radially symmetrical, about 8 cm in diameter, and have six tepals. The outer tepals are obovate and drooping, and the base suddenly tapers to a claw-like part. The inner tepals are elliptical oblanceolate, smaller than the outer tepals, stand upright, and fuse with the outer tepals at the base to form a short flower tube. The outer tepals have a purple twill pattern on a yellow background in the center of their base, which is said to be the origin of the name ayame. The stamens emerge from the base of the outer tepals and grow opposite them, the anthers face downward, and the three style branches are petal-like and closely cover the stamens. Nectar comes out from the inside of the flower tube, and bees that sneak between the outer tepals and the style branches to suck nectar leave pollen on their backs and then visit other flowers to pollinate them. The flowering season is from May to July. It grows in dry grasslands and is distributed throughout Japan, as well as in eastern Siberia, northeastern China, and the Korean Peninsula. It is also widely cultivated for decorative purposes, and there are varieties such as the white-flowered white iris, the Japanese iris with large inner tepals that open flat, and the dwarf banyan iris. The Japanese iris is a variety of iris with stiff, twisted leaves and downward-facing buds.

There are about 200 species of Iris distributed in the temperate zone of the Northern Hemisphere, and in Japan, in addition to Iris serrata, eight species grow wild: Iris ehime, Iris dwarf, Iris scabra, Iris amaranth, Iris japonica, Iris nohanabu, and Iris lily. There are also many horticultural species, such as Iris ichihatsu, Iris hanabu, German iris, and Dutch iris.

When one is unsure of what to choose, the saying goes, "I'll choose either the iris or the Japanese iris," but the Japanese iris is a wetland plant that grows in ponds and marshes, is much larger overall, and has only elongated, simple yellow spots on its outer petals. This is based on a story about Minamoto no Sanmi Yorimasa in the "Taiheiki," a poem he wrote when he was at a loss as to which companion to choose from among the many court ladies at the Imperial Court: "In the May rains, the mako of the stream fills with water, and it is difficult to choose between the iris and the Japanese iris."

[Takemi Shimizu May 21, 2019]

Irises

The Japanese iris and its wild species, Iris orbiculatus, are often mistaken for true irises. Japanese plants that are similar to irises are Iris cernua and Iris quinqueradiata. Iris cernua and Iris quinqueradiata have leaves with a raised ridge in the center that serves as the main vein, but the other three species have no clear midvein and are smooth. Iris cernua has a pointed, beak-like fruit tip, but the other three species do not. The yellow part at the base of the outer perianth also has no veins. Iris gardens and iris festivals are all based on Iris cernua, which is the source of the confusion. In the wild, irises usually grow in dry, sunny grasslands, Iris cernua in highland marshes, Iris cernua in lowland marshes near water, and Iris cernua in cold regions and highland marshes.

[Kiyoro Yoshie May 21, 2019]

Cultural history

The leaves are arranged side by side and are considered to form a pattern, which is said to be the origin of the name ayame. Many of the 12 poems in the Man'yoshu that use the name ayame-gusa are combined with the lesser cuckoo, which is also known as the lesser cuckoo because of the stripes on its chest. From Heian literature to Basho, ayame, ayame-gusa, ayame-buki, etc. refer to the Japanese iris of the Araceae family (APG classification: Acoraceae). The modern ayame is a name that was originally used to refer to the Araceae iris, which was called hana-ayame during the Genroku period (1688-1704), but the name shobu was later replaced by ayame to refer to the Iridaceae iris, and later the "hana" (flower) was dropped and it came to be called simply ayame.

[Hiroshi Yuasa May 21, 2019]

iris
There are six tepals. The base of the outer tepal has a purple twill pattern on a yellow background. It grows wild in sunny mountainous areas. The flowering season is from May to July. ©Seishohmaru ">

iris

Major species of the genus Iris (1) [Pictures of specimens]
©Kanzo Otawa ">

Major species of the genus Iris (1) [Pictures of specimens]

Major species of the genus Iris (2) [Pictures of specimens]
©Kanzo Otawa ">

Major species of the genus Iris (2) [Pictures of specimens]

Ichihatsu
The flowering season is from April to May. The outer tepals are obovate, and the inner surface below the center is densely covered with white fleshy protuberances with purple spots. ©Seishohmaru ">

Ichihatsu

Iris
The leaves are sword-shaped and 30-70cm long. In May and June, blue-purple flowers bloom at the end of the flower stalk. The outer petals droop and have white or pale yellow markings along the midvein. ©Seishohmaru ">

Iris

Iris japonica
The flower stalk branches upward and produces white to pale purple flowers. It is the only evergreen species in the Iridaceae family. ©Shogakukan ">

Iris japonica

German Iris
A representative species of rhizome plant, it is known as the "rainbow flower" because of its rich variety of flower colors. Also known as German iris ©Shogakukan ">

German Iris

Dutch Iris
It is a representative bulbous iris, and its flower colors include blue, purple, white, and yellow. Also known as Dutch iris .

Dutch Iris

Wild iris
In June and July, several reddish purple flowers bloom. The outer petals are elliptical, and there are yellow spots from the center down along the midvein. Also known as Japanese iris ©Shogakukan Photo by Masatoshi Hirose ">

Wild iris

Japanese Iris
A horticultural variety of Japanese iris. Improvement and breeding began in the Edo period, and there are many varieties. ©Shogakukan Photo by Masatoshi Hirose ">

Japanese Iris

Iris arvensis
It grows in clusters in subalpine wetlands and high moors, and blooms blue-purple flowers in July and August. The outer petals are broadly obovate and drooping, with yellow and purple tiger stripes at the base. ©Shogakukan Photo by Fujio Aoyama ">

Iris arvensis

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

Japanese:

アヤメ科（APG分類：アヤメ科）の多年草。根茎は横に伸び、硬く、褐色の繊維に覆われる。葉は長さ30～50センチメートル、幅5～10ミリメートル、2列に互生し、跨(こ)状に並び、細い中央脈がある。花茎は高さ30～60センチメートルで、分枝しない。花は放射相称、径約8センチメートル、花被片(かひへん)は6枚、外花被片は倒卵形で垂れ下がり、基部は急に細くなって爪(つめ)部となる。内花被片は楕円(だえん)状倒披針(とうひしん)形で、外花被片より小さく、直立し、基部は外花被片と合着して短い花筒をつくる。外花被片の基部中央には黄色地に紫色の綾目(あやめ)模様があり、これがアヤメの名のおこりとする説がある。雄しべは外花被片の基部から出てこれと対生し、葯(やく)は下向き、花柱分枝は3個で花弁状、雄しべと密着してこれを覆い隠す。花筒の内側に蜜(みつ)が出るが、吸蜜のため外花被片と花柱分枝間に潜り込んだハナバチ類は、背中に花粉をつけて去り、やがて他花を訪れてこれを受粉させる。花期は5～7月。乾燥した草地に生え、日本全土のほか、シベリア東部、中国東北部、朝鮮半島にも分布。観賞用としても広く栽培され、白花のシロアヤメ、内花被片が大きくて平開するクルマアヤメ、矮性(わいせい)のチャボアヤメなどの品種がある。カマヤマショウブはアヤメの変種で、葉は堅くてよじれ、つぼみは下向きにつく。

　アヤメ属は北半球の温帯に200種ほど分布し、日本にはアヤメのほか、エヒメアヤメ、ヒメシャガ、シャガ、ヒオウギアヤメ、カキツバタ、ノハナショウブ、ヒオウギの計8種が自生する。イチハツ、ハナショウブ、ジャーマン・アイリス、ダッチ・アイリスなど園芸種が多い。

　物事の選択に迷うとき「いずれ、アヤメかカキツバタ」といわれるが、カキツバタは湿生植物で池沼に生え、全体がずっと大きく、外花被片には細長い単純な黄斑(おうはん)があるにすぎない。これは、『太平記』の源三位頼政(げんざんみよりまさ)の故事、つまり宮中で大ぜいの女官のなかから伴侶(はんりょ)を選ぶ際に困り果てて詠んだ歌「五月雨(さみだれ)に沢辺のまこも水たえていづれあやめと引きぞわづらふ」にちなむ。

［清水建美　2019年5月21日］

アヤメ類

真正のアヤメと間違われるのは、ハナショウブとその野生種であるノハナショウブである。またアヤメによく似る日本産の植物はヒオウギアヤメとカキツバタである。ハナショウブとノハナショウブは葉の中央が隆起して稜(りょう)があり、中央脈という主葉脈となるが、他の3種には明瞭(めいりょう)な中央脈がなく、葉面は平滑である。またノハナショウブは果実の先がとがり、くちばし状となっているが、他の3種にはそれがない。また外花被の基部の黄色部には脈がない。アヤメ園とかアヤメ祭りというのはすべてハナショウブが材料となっており、誤解のもととなっている。野生状態では、アヤメは乾燥する日当りのよい草原に、ノハナショウブは高地の湿原に、カキツバタは低地の湿地水辺に、ヒオウギアヤメは寒地や高地の湿原に生えるのが普通である。

［吉江清朗　2019年5月21日］

文化史

葉が並列して立っている姿が文目(あやめ)（紋様）をなすとみなされ、アヤメの名の由来とされている。『万葉集』にアヤメ草の名で12首詠まれているものの多くが、ホトトギスとの組合せであるが、これはホトトギスが、胸の縞(しま)模様から「文目鳥(あやめどり)」の別名をもつこととも関連している。平安文学以降、芭蕉(ばしょう)に至るまで、アヤメ、アヤメ草、アヤメ吹きなどとあるのはサトイモ科（APG分類：ショウブ科）のショウブのことである。現在のアヤメは、元禄(げんろく)時代（1688～1704）に花アヤメとよばれたサトイモ科のアヤメが、ショウブの名に置き換わって、アヤメ科のアヤメをさすようになり、その後「花」がとれ、単にアヤメとよばれるようになったものである。

［湯浅浩史　2019年5月21日］

アヤメ
花被片は6枚。外花被片の基部には、黄色地に紫色の綾目模様がある。日当たりのよい山地に多く自生する。花期は5～7月©Seishohmaru">

アヤメ

アヤメ属のおもな種類(1)〔標本画〕
©大多和鐘三">

アヤメ属のおもな種類(1)〔標本画〕

アヤメ属のおもな種類(2)〔標本画〕

イチハツ

カキツバタ

シャガ

ジャーマン・アイリス

ダッチ・アイリス

ノハナショウブ