CHICO FORESTRY SUBSTATION STUDIES OF TREE GROWTH. 109 



girth, breast-high. In 1902, three girthed 36, 40, and 46 inches. 

 Young catalpas planted in 1895, when 3 feet high, are now (1902) 18 

 feet high and girth 12 inches. The catalpa seems to produce on a given 

 area in a given time about twice the amount of wood as does the well- 

 known Western box-elder (Negundo Calif arnica), which is often planted 

 for its rapid growth. Neither species, however, begins to yield as much 

 wood as the paulownia. 



The Paulownia imperialis of Japan is very little known, but it grows 

 with such rapidity here that its more frequent growing can be recom- 

 mended. Some remarkable measurements of this tree have been given 

 in previous reports. This year (1902) one was measured which in two 

 years had grown from an old stump to a height of 25 feet with a girth 

 of 15 inches and was well-branched about 15 feet from the ground. 

 Numbers of the older paulownia planted in 1889 are over 40 inches in 

 girth; three, measured "as they came,' 7 were 45, 48, and 49 inches. 

 One of the largest, near the grove of sequoias, girths 5-J feet. The com- 

 mercial value of paulownia wood in California has not yet been deter- 

 mined, but many small articles of Japanese manufacture, such as toys, 

 boxes, and furniture, are made of this light-brownish timber. 



Several species of Celtis (nettle-tree) have grown very fast here. The 

 best is Celtis australis, which, planted in 1896, now girth 12 and 14 

 inches and are 16 to 18 feet high. C. occidentalis, somewhat older, has 

 also made very fine growth. C. orientalis is much behind the others. 

 These are all trees of easy cultivation. 



One of the disappointments here is the growth of Zelkova keaki, which 

 ranks as the best hardwood of Japan. A lot of trees were obtained in 

 1895 and several thousand trees grown. These were widely distributed, 

 and a block was planted here. The trees have never straightened up or 

 made much growth. The increase of wood is only about one quarter 

 that of American ash and half that of English oak. The tree does no 

 better anywhere else, so far as tested in California. 



The Ashes ha.ve deservedly attracted attention here, and no other 

 hardwood better justifies planting for timber in this region, if the best 

 species be used. Fraxinus dimorpha is small and slow of growth, but 

 a beautiful ornamental. It comes from Algeria. Trees planted in 1896 

 are now (1902) 10 and 12 feet high, girthing 7 and 8 inches. Fraxinus 

 kabyla, also from Algeria, is a much more striking species. Four meas- 

 ured (eight years from seed) girthed 16, 18, 19, and 20 inches, and they 

 are 18 to 20 feet high, with fine trunks. Fraxinus oregona, of the same 

 age, are only two thirds as large. Fraxinus viridis is also much poorer 

 than F. kabyla. Fraxinus alba, however, the well-known American white 

 ash, ranks in point of growth somewhat nearly with F. kabyla. Trees 

 grown from seed in 1892 are now, ten years later, about as large as F. 

 kabyla trees of eight years of age, and a few are even larger. The differ- 

 ence so far is perhaps ten per cent in favor of the foreigners. The older 

 white ashes, in some cases, fourteen years of age, are very fine trees. 

 One is 40 feet high and 3 feet in girth, and all are nearly as large as this. 

 The best single ash upon the substation, considering age, is a white ash 

 eleven years old, planted on the main avenue. It is 30 feet high, 10 

 feet to the lowest branch, and girths 28 inches. The growth of ash 

 timber on such land as this should attract attention, as evidently in 

 twenty or twenty-five years some cutting could be done. The growth 

 of the white and the Kabyla ashes here has been about equal to that of 



