BUEEAU OF PLANT INDUSTRY. 259 



of farmers, fruit powers, and others taking up land in connection 

 "with the reclamation work are some of the projects requiring the 

 department to acquire the use of land and to maintain on such lands 

 certain public improvements. 



Some of these lines of investigations are of such a nature as to re- 

 quire their continuance without interruption or material modification 

 through a long term of years and, under a plan of coordination of the 

 work at many stations located in different States, it is believed that it 

 will eventually be found practicable to secure this permanency 

 entirely through cooperation with the State experiment stations, such 

 as is now in effect at most of the places where investigations of this 

 nature are being carried on. The policy of the bureau is, therefore, 

 to recognize that in the establishment and management of these field 

 stations it is assuming a more or less temporary responsibility which 

 ultimately will be transferred to the experiment stations as the proper 

 agents for the permanent holding of lands and improvements within 

 the State where they are located. The policy, furthermore, is to de- 

 velop as rapidly as possible a thoroughly coordinated system of co- 

 operation between the department and groups of State experiment 

 stations for the investigation of problems of such character as can not 

 be successfully solved by the several stations working independently 

 of each other and of the department. 



It is highly important, however, that the bureau shall have au- 

 thority to take care of its men and its work at these stations by fur- 

 nishing proper temporary buildings and by erecting fencas and struc- 

 tures for stock and machinery whenever necessary, and as the co- 

 operative work with the State experiment stations develops to trans- 

 fer such improvements to the State station or to dispose of them by 

 the usual process of law. 



LABORATORY OF PLANT PATHOLOGY. 



Studies have been continued under the direction of Dr. Erwin F. 

 Smith on the various diseases of plants under investigation with very 

 good results, some special lines of work having been completed and 

 reported upon in bulletin form. Chief among the latter may be men- 

 tioned the following: 



Crown-gall-of plants. — The greater effort of the laboratory dur- 

 ing the entire year has been centered upon crown-gall of plants. A 

 full report in bulletin form was published, giving the life history and 

 cultural characters of the causal organism; pointing out the difficul- 

 ties attending its isolation and identification during the seven years 

 of stud}' devoted to the disease; its wide range of host plants: numer- 

 ous illustrations showing the nature of the tumors produced, time of 

 their production, etc. The striking similarity of crown-gall of plants 

 to certain malignant animal tumors was also pointed out. Later, in a 

 circular, this phase was taken up in detail, several new facts being 

 brought out. and an additional bulletin will soon be ready for publi- 

 cation to fully illustrate the interesting results obtained in connec- 

 tion with this study. 



Tumor disease of ltmes and other citrus fruits. — Further study 

 with excellent results has been made on the destructive tumor disease 

 of citrus fruits. The bulletin which was ready for publication last 



