BUREAU OF PLANT INDUSTRY. 285 



INVESTIGATIONS IN FOREST PATHOLOGY. 



The work of the Bureau on forest diseases, which is conducted in 

 close cooperation with the Forest Service, has continued in charf^e 

 of Dr. Haven Metcalf, Pathologist. The diseases of ornamental and 

 shade trees have also been studied in connection with the work. 



Blister rust of white pine. — The work of Dr. Perley Spaulding, 

 Pathologist, in controlling the imported blister rust of the white pine 

 has been continued Avith very gratifying success. It is believed that 

 the disease, although introduced into many localities, has thus far 

 been prevented from obtaining a permanent foothold in the United 

 States. Public opinion has become thoroughly aroused to the seri- 

 ousness of the danger from this disease, and in consequence no im- 

 portations by States and but few by private individuals are known 

 to have been made this year. A National law prohibiting such irre- 

 sponsible importation as may be still going on is very urgently needed. 

 No other method of preventing further importation of the disease 

 is practicable. Care has been taken to undertake no work on this dis- 

 ease Avhich could be undertaken by the inspection authorities of the 

 several States concerned. Despite this fact the funds available have 

 proved insufficient for the work, and an appreciable part of the field 

 expenses have been defrayed through a cooperative arrangement by 

 the State of New York and a commercial paper company, in order 

 that imperative work might be accomplished without dangerous 

 dela}'. A fundamental bulletin on this disease is now in press. 



Blight of coniferous seedlings. — The work of two seasons at 

 Halsey, Nebr., on this disease b}^ Doctor Spaulding and Mr. Carl P. 

 Plartley, Assistant, shows conclusively that it is easily cbntrolhible 

 by sliglit and perfecth^ practicable changes in management of water 

 and shade in the nursery. This disease is one of the great factors 

 determining success or failure in western forest-nursery jji-actice riud 

 reforestation. The precise cause of the disease is still undetermined. 

 A brief bulletin on this subject will soon be submitted for publication. 



DA:MriNG-OFF OF EUCALYPTUS SEEDLINGS. — "Work at the Lytle Creek 

 nursery of the Forest Service in Lytle Creek canyon, California, by 

 Dr. Perley Spaulding and Dr. A. H. Graves, Expert, shows that this 

 disease, previously the cause of widespread loss in eucalyptus grow- 

 ing, is for all practicable purposes preventable by using the proper 

 type of soil for planting. A circular on this subject will shortly be 

 issued. 



Funda:mental facts of forest pathology. — As the work of this 

 office has progressed it has become increasingly evident that the re- 

 searches in forest pathology made by European investigators are only 

 very superficially applicable to American conditions. Accordingly 

 it is necessary to conduct researches into the fundamental facts of tlie 

 science. Such a piece of research is embodied in a bulletin prepared 

 by Doctor Spaulding, entitled " The Timber Rot Caused by Lenzites 

 Sepiaria," which discusses one of the most common causes of timber 

 rot in America. 



WoiJK IN the National Forests. — The work of the forest-disease 

 survey, conducted by Dr. George G. Hedgcock, Pathologist, as well 

 as statistics collected by the Forest Service, indicate that in America 



