FOREST FLORA OF JAPAN. 



INTRODUCTION. 



Many years ago, in one of the most interesting papers ^ which has been written on the dis- 

 tribution of forests, Professor Asa Gray drew some comparisons between the forests of eastern 

 North America and those of the Japan-Manchurian region of Asia. Here it was shown that, 

 rich as eastern America is in tree species, Japan, and the regions to the north of it,^in spite 

 of their comparatively small area, are still richer. Professor Gray's Asiatic region included the 

 four principal Japanese islands, eastern Manchuria, and the adjacent borders of China, while 

 the contrasted American region embraced the territory east of the Mississippi Eiver, but 

 excluded the extreme southern point of Florida, inhabited by some sixty tropical trees which 

 belong to the West Indian rather than to the true North American flora. In the Japan- 

 Manchurian region he found 168 trees divided among sixty-six genera, and in eastern America 

 155 trees in sixty-six genera, the enumeration in both cases being confined " to timber-trees, 

 or such as attain in the most favorable localities to a size which gives them a clear title to the 

 arboreous rank." In the Japanese enumeration were included, however, a number of trees 

 which are not indigenous to Japan, but which, as we now know, were long ago brought into 

 the empire from China and Corea, like most of the plants cultivated by the Japanese. Early 

 European travelers in Japan, like Thunberg and Siebold, who were unable to penetrate far into 

 the interior, finding a number of plants common in cultivation, naturally believed them to be 

 indigenous, and several Chinese plants were first described from individuals cultivated in 

 Japanese gardens. Later writers ^ on the Japanese flora have generally followed the example 

 of the early travelers, and included these plants in the flora of Japan. Indeed, it is only 

 very recently that it has been possible to travel freely in all parts of the empire, and to study 

 satisfactorily the character and distribution of its flora. 



The list of Chinese and Corean trees cultivated in Japan, and usually enumerated in Floras 

 of the empire, includes Magnolia conspicua. Magnolia parvifolia, Magnolia Watsoni, Sterculia 

 platinifolia, Cedrela Sinensis, Zizyphus vulgaris, Koelreuteria paniculata, Sapindus Mukorosi, 

 Acer trifidum, Ehus vernicifera, Sophora Japonica,* Prunus Mume, Pyrus Sinensis, Crataegus 

 cuneata, Eriobotrya Japonica, Liquidambar Formosana (Maximowiczii), Cornus officinalis, 



1 Forest Geography and Atchseology, Scientific Papers, ii. through the entire country, especially in the foliaceous for- 

 204. ests of the north." He had evidently confounded Sophora 



2 See Franchet & Savatier, Enum. PL Jap. — Forbes & with Maackia, a ^ommon and widely spread tree, especially 

 Hemsley, Jour. Linn. Soc, xxiii. and xxvi. in Yezo. Sophora, which is only seen occasionally in gar- 



' Even Rein (The Industries of Japan), usually a most dens, does not appear to be a particularly popular plant with 

 careful observer, states that Sophora Japonica is " scattered the Japanese. 



