BUREAU OF PLANT INDUSTRY. 297 



"Work in Kentucky and Maryx,and. — The study of the compara- 

 tive value of several strains and varieties of Burley tobacco and of 

 the fire-cured tyjDes is being continued at Lexington and Hopkinsville 

 in Kentucky. Tests are being made at Hopkinsville to determine 

 the best available source of phosphorus for the tobacco crop. In 

 Maryland the prolonged drought has made it impossible to carry out 

 certain features of the investigations this year, but the fertilizer ex- 

 periments are being continued and special tests as to the possibility 

 of utilizing cowpeas, crimson clover, and vetch in improving the 

 tobacco lands without injuring the quality of the tobacco have been 

 taken up. 



Work in Virginia, — A change in the plan of conducting the co- 

 operative tobacco experiments in Virginia has been made, whereby 

 the management of the local stations in the several tobacco districts 

 is left in the hands of the State experiment stations, while the super- 

 vision of the tobacco work at these stations remains with the bureau. 

 The experiments and demonstrations are being continued along prac- 

 tically the same lines as in the past. 



Work in North Carolina and South Carolina. — Owing to the 

 largely increased appropriation of the State in support of the work 

 the investigations in North Carolina have been very much extended 

 this year, and experiments are now in progress in each of the three 

 sections of the State producing different modifications of the flue- 

 cured t.ype. The various local types and strains of tobacco are being 

 given comparative tests as to yield and quality of leaf produced and 

 two new hybrids are being developed to secure increased yields. Fer- 

 tilizer tests and crop-rotation studies with special reference to the use 

 of cowpeas and crimson clover as soil improvers are in progress at 

 each of the three local stations. It is planned to utilize the experi- 

 mental data thus obtained as rapidly as available in making prac- 

 tical demonstrations in cooperation with leading growers in improved 

 methods of tobacco production. 



Experiments in improved methods of flue curing have been taken 

 up and investigations looking to the control of the Granville wilt have 

 been continued in Granville County, these features of the work being 

 conducted in cooperation with the State station. 



The work in South Carolina, which is located in Florence and 

 Clarendon Counties, is along essentially the same lines as in North 

 Carolina and includes tobacco breeding and variety tests, fertilizer 

 experiments, and crop-rotation studies. 



PLANT-NUTRITION INVESTIGATIONS. 



The investigations in charge of Dr. W. W. Garner relating to 

 some of the fundamental problems in plant nutrition of a general 

 nature have been continued along the same lines as last year. The 

 work includes laboratory studies and field experiments under vary- 

 ing soil and climatic conditions, the facilities at the Arlington Ex- 

 perimental Farm being utilized as far as practicable. 



Relation of nutrition to tiir character and composition of the 

 PLANT. — The specific influence of the various elements of plant food 

 on the production of the valuable constituents of agricultural plants 

 is being investigated. Much work has been done with cotton and 



