AN ORCHARD OF CHESTNUT HYBRIDS' 



j. A. Detlefsen and W. A. Ruth 

 College of Agriculture, University of Illinois, Urbaiia, Illinois 



A HYBRID BETWEEN JAPANESE AND AMERICAN CHESTNUTS 



Figure 7. In 1898 Mr. Endicott was successful in obtaining five chestnuts by crossing 

 the Japanese and American species. From these he raised three trees, of which this is 

 the largest. The trees were remarkably vigorous and fruited precociously, one at seventeen 

 months, one at four years, and the other at five years of age. The Japanese chestnut does 

 not usually begin to bear until it is six years old, the American at about twelve years. See 

 text, p. 306. 



WITH the rapid disappearance from 

 the American continent of the na- 

 tive chestnut tree through the rav- 

 ages of the chestnut bark disease, there 

 has come the demand for a substitute. 

 The discovery in China of a species of 

 chestnut resistant to this disease, and the 

 ease with which hybrids between the differ- 

 ent species can be produced has led to the 

 hope that hybrid chestnut trees may take 

 the place of the native American species. 

 Mr. J. F. Rock, the agricultural explorer, 

 is now in China collecting all the species 

 of chestnuts he can find there in order 



article, which calls attention to what a 

 single plant breeder was able to do with 

 the material at his disposal, has a direct 

 bearing on this important problem. 



In many parts of the Appalachian Moun- 

 tains the chestnut is, or was, the most 

 abundant and important forest tree. In 

 some places it made up fifty per cent of 

 the hardwood timber; and it has been 

 estimated to have constituted at least ten 

 per cent of all the hardwood forests in 

 the eastern United States, before the 

 ravages of the bark disease began. Unless 

 it is possible to develop a resistant hybrid 



that this breeding material may be placed that can be easily propagated, one of our 



in the hands of American plantsmen, to be most beautiful and useful trees is doomed 



used for crossing with the native species to disappear from American forests. 

 to develop the new hybrid chestnut. This Editor. 



^ Paper No. 19 from the Genetics Laboratory, College of Agriculture, University of 

 Illinois. The writers are indebted to Professor J. C. Blair, who furnished some of the facts 

 relating to the early history of this orchard and also made possible an opportunity to visit it. 



305 



