BUREAU OF PLANT INDUSTRY. 399 



Chestnut bark disease. — Investigations in immediate charge of 

 Prof. J. F. Collins indicate that the chestnut bark disease has con- 

 tinued to spread, and can now probably be found over the entire 

 range of the chestnut. Many new facts regarding the disease have 

 been brought to light. The public demand for information and 

 advice has been unprecedented, and to supply it has consumed a large 

 share of the energies of the office. Much time has been given to ad- 

 vising private owners in districts already infected in relation to the 

 destruction or care of the diseased trees in order to delay the spread 

 of the disease. Some investigators entertain the hope that the disease 

 may become inactive after a few years. If this hope should be real- 

 ized, it is all important that its progress be delayed in the meanwhile 

 as much as possible. 



The emergency appropriation for work on the chestnut bark disease 

 necessitated a great increase in activity along this line during the 

 present j^ear. All work will be organized in close cooperation with 

 the States concerned, particularly Pennsylvania and Virginia, which 

 already have appropriations for this work. Many of the most funda- 

 mental facts regarding the disease are still to be determined, so con- 

 siderable energy must be put into pure investigation as well as into 

 direct efforts to suppress the disease. It is planned to give consider- 

 able attention to conditions in those States where infection is appar- 

 ently slight, such as North Carolina, Tennessee, Kentucky, Virginia, 

 West Virginia, and Ohio. 



White-pine blister rust. — Continued work against the blister rust 

 of the white pine, under the immediate charge of Dr. Perley Spauld- 

 ing, has disclosed the presence of the disease in many plantations of 

 imported trees hitherto regarded only as suspicious. In one case tree^ 

 in which the disease had apparently remained dormant for five 

 years exhibited this season the most severe attack of the disease yet 

 seen in America. It is obvious that no inspection of these trees at 

 the time of their importation could have shown their real condition. 

 A bulletin on the present status of this disease in America is ready 

 for press. 



The passage of the plant-quarantine bill makes it probable that 

 white pines will not longer be imported from Europe. The planta- 

 tions of imported pines already here, however, will have to be closely 

 watched for an indefinite period. Extensive investigations are con- 

 templated of the actual status and danger from other imported dis- 

 eases, at present inconspicuous, particularly on ornamental tree 

 stock. 



Forest hygiene. — Work bearing on forest hygiene under the im- 

 mediate charge of Dr. George G. Hedgcock has continued on the 

 same lines as heretofore, in close cooperation with the Forest Service. 

 The work has been extended so that there are now cooperating 

 pathologists in four of the six national forest districts. In view of 

 the policy of the Forest Service to include snags and dangerously 

 diseased trees in tlie contracts for cutting when timber sales are 

 made, this work will necessarily be continued and extended. A bul- 

 letin by Dr. E. P. Meinecke, bearing particularly on conditions in 

 California and Nevada, has been issued. 



• Correspondence relating to the control of diseases of ornamental 

 trees and shrubs is at present so heavy as to take about one person's 



