After visiting Ukishima bog-woodland in Shingu I took the express train back to Kushimoto. My quest was for a yellow-flowering toad lily, which reportedly grows wild in the southern Kii Peninsula.
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Rare yellow-flowered toad lilies (Tricyrtis macranthopsis) bloom in the deep-shaped forests of the southern Kii Peninsula. |
Let's take a brief look at the toad lily genus. There are estimated to be 20 species of toad lilies in the genus Tricyrtis. All are from Asia, from Nepal eastwards through China, Korea, Japan, Taiwan and the Philippine Islands. The genus belongs to the lily family or Liliaceae; all are herbaceous perennials. Many have rhizomatous root systems. Tricyrtis thrive in cool damp soil with plenty of humus.
Japan itself is home to around 11 species. Some are very rare in the wild, and are very difficult to cultivate.
The reasons for the English name toad lily are obscure. The commonest species of toad lily in Japan is hototogisu (Tricyrtis hirta); the Japanese name derives from the songbird (cuckoo, Cuculus poliocephalus) of the same name, whose breast markings the mottled purple and white markings on the flower are said to resemble.
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Brown spots fleck the inside of the blossoms. |
Like all toad lilies, hototogisu requires a shaded or woodland position to grow and bloom. It is easy to grow in containers and is readily available in garden centers. The tapering, elliptic-lanceolate leaves alternate on the arching stems; the purple-white flowers are borne in the leaf axils along the stems, which vary in length from 30-100 cm. This species is very easy to propagate by dividing the wiry white roots during the dormant season. T. hirta grows in low mountains from southwest Hokkaido through Honshu, Shikoku and Kyushu. It will tolerate temperatures as low as minus 15 C.
The yellow-flowered species, Kii joro hototogisu (Tricyrtis macranthopsis), grows in scattered locations from the base of Mount Fuji to the southern Kii Peninsula, Kochi, Miyazaki and Kagoshima prefectures.
The weather forecast was not good on the morning I chose to go plant hunting -- chance of rain 90 percent. By midmorning the forecast proved accurate, and when it rains in Kii, it pours.
I had read in a guidebook that Kii joro hototogisu grew along the Kozagawa River. The Kozagawa River rises from the forested slopes of Mount Otoyama (1,122 meters), between the towns of Kozawa and Oto, the tallest peak in the south Kii area. The river flows through beautiful forested country; all the valleys are steep and have a romantic appeal.
Still, rainfall on and around Mount Otoyama is 4,000 mm per annum, due to the warm Kuroshio Current I mentioned in my last article. On Mount Otoyama the native Japanese beech forest flourishes, though the beech trees (buna, Fagus crenata) around Otoyama have smaller leaves and darker trunks than their Tohoku relatives.
On the same mountain slopes and valleys that face toward the ocean there is evergreen laurel forest (shoyo-jurin) growing. This laurel forest follows the course of the Kozagawa River some 60 km from the source to the sea, with evergreen oak trees species such as ara-kashi (Quercus glauca), aka-gashi (Q. acuta), ichi-gashi (Q. gliva), shira-kashi (Q. myrsinaefolia), urajiro-gashi (Q. salicina) and tsukubane-gashi (Q. sessilifolia).
Not only natural forest grows in southern Wakayama, especially around Koza. This area has many plantations of Japanese cedar (sugi, Cryptomeria japonica) and cypress (hinoki, Chamaecyparis obtusa), grown for construction timber or for pulp.
Koza's scenery offers many natural waterfalls and unusual rocks. The most famous rock formation is Ichimai- iwa, a national natural monument. The sheer rock face rises 100 meters and stretches 500 meters along Route 371 on the banks of the Kozawa River, approximately 13 km from Kushimoto. Mushikui-iwa ("worm-eaten rock") is another natural monument, about 4 km from Koza town.
Ichimai-iwa has a small tourist office, and to escape the weather I turned in here. The assistant in the tourist office kindly pointed out, with the aid of a telescope, the yellow toad lilies growing happily on the steep slopes of Ichimai-iwa, and 100 meters up the road from the tourist office there were more.
In both cases Kii joro hototogisu was growing on steep rock faces that received little or no sun. The stems were 80-150 cm in length and hung downward on the steep rock face. It is interesting to note that, while horticulture books state that humus-rich soil is required for successful cultivation, here, close to Ichimai-iwa, the yellow toad lily grew in very shallow soil.
The yellow flowers bloom from August to the end of October. They are tubular-campanulate, 3-4 cm long. The exterior is clear yellow and the interior of the flower is covered with brownish-purple dots. It was a pretty sight growing in the wild.
Iwa-tabako (Conandron ramondioides), a member of the gloxinia family (Gesneriaceae), grew side by side with T. macranthopsis. Its purple flowers open in August. With luck you may be able to see flowers at the same time.
During the 1970s a new species of Tricyrtis was discovered in southern Cotabata in the Philippine Islands and named T. imeldae, after Imelda Marcos, then the first lady of the Philippines.
The Kozagawa River is also well known for sweetfish (ayu). Even if you don't go in search of the elusive Tricyrtis macranthopsis, this area has much to offer the nature lover. Just remember: Take nothing but pictures, leave nothing but footprints.