BUEEAU OF PLANT INDUSTRY. 153 



yield of fiber it is more profitable also for the fiber producer. Variety 

 selection is being continued by this department for the further 

 improvement of special strains. 



Sudan grass. — Sudan grass, introduced by the department and 

 first distributed in 1912, has proved remarkably successful as a hay 

 crop in the Middle and Southwestern States, and the acreage now 

 planted is very large. Numerous related varieties have now been 

 secured from Africa and are being tested, especially the dwarf 

 varieties with larger grain that may be harvested like oats. 



Denia onion seed, — It has been determined that in several im- 

 portant localities high-grade onions of the Denia type can be pro- 

 duced from imported seed. Several lots of American-grown seed 

 have been produced, and from this bulbs of high quality have 

 resulted, thus indicating that it may be possible to successfully pro- 

 duce in this country a grade of Denia onion seed which will give 

 results quite as satisfactory as have been obtained from imported 

 seed. 



Chinese dry-land elm. — Tests of the Chinese dry-land elm {Ul- 

 rrhus pumila) carried on in nursery rows at Mandan, N. Dak., have 

 shown this tree to be exceptionally well adapted both to the climatic 

 and soil conditions of this region, and it is therefore believed that 

 this species will become a valuable shelter-belt and ornamental tree 

 for the northern plains region. Much more extensive plantings 

 throughout various areas of this region will be completed by the 

 close of the present season. 



Jujubes. — Previous introductions of jujubes, which were distrib- 

 uted in 1906 and 1907, are beginning to bear fruit in various parts 

 of the country. The trees have withstood temperatures of 22° below 

 zero and appear to be promising for dooryard culture at least in the 

 loess soils of the Great Plains region. They have grown well in 

 central Texas and Arizona, and wide distributions are being pre- 

 pared for. The department has already a considerable collection of 

 varieties of this fruit, of which in China there are believed to be 

 hundreds of distinct different sorts. 



Foreign explorations. — The agricultural exploration of China has 

 resulted in the discovery and introduction of several promising 

 plants, the more important of which are special varieties of persim- 

 mons, which are used on a large scale for drying purposes by the 

 Chinese, and large-fruited varieties of the Chinese chestnut. A 

 species of this chestnut introduced in 1906 has proved resistant to the 

 bark disease. 



Acclimatization or the avocado in the United States. — As a re- 

 sult of the numerous experimental plantings that have been made in 

 California and Florida, the eventual development of a large industry 

 comparable to that of citrus-fruit production is to be expected. 

 Though still unfamiliar to the American public, the avocado is a 

 food product of high nutritive value, and is adopted as a regular 

 article of diet by most of the European and American residents of 

 Tropical America. With adequate supplies available at low prices 

 the consumption of this tropical fruit might be expected to attain 

 large proportions as in the case of the banana. 



