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DISEASES OF TAXODIUM AND LIBOCEDRUS. 67 
THE ‘* PIN’’ DISEASE OF LIBOCEDRUS DECURRENS. 
HISTORICAL. 
In 1879 Harkness * published a note in which he called 
attention to a peculiar rot which occurs in the heart 
wood of the incense cedar, Libocedrus decurrens. Mayr t 
mentions what is evidently the same disease and describes 
it as follows: ‘* A certain fungus, Daedalea vorax, appears 
to be very destructive, destroying the heart wood of stand- 
ing trees ; the fungus colors the wood red-brown and forms 
large lens-shaped cavities, at the same time the wood 
becomes very ‘*‘ briichig.’’ In 1896 the following appeared 
in Sargent’s Silva: ¢ ‘* The trunks of Libocedrus decurrens 
are frequently honey-combed and its value destroyed as a 
timber tree by Daedalea vorax, which destroys rounded 
masses of wood, disposed in long rows, sometimes extend- 
ing through the length of the trunk, reducing them to a 
cinder-like powder.’’ In the note published by Harkness 
one is led to believe that Daedalea vorax attacks Abies 
Douglasii, — not Libocedrus. Daedalea vorax is reported 
as growing on Libocedrus decurrens by Harkness.§ Ina 
letter received from Dr. Harkness last year he says: 
‘¢ Daedalea vorax is a fungus which causes the rot in Adies 
Douglasii,’’ etc. As to the Libocedrus disease he says: 
‘¢ Nothing could be found except. mycelium which per- 
meates through the diseased portion. No visible signs of 
any spores were seen. A careful search fails to reveal 
any of the fungus either among the roots or the surface of 
the tree, nothing indeed to indicate its presence until the 
tree has been felled.’’ He says furthermore that the note 
* Harkness, H. W. A foe to the lumberman. (Pacific Rural Press. 
Jan. 25, 1879.) 
+ Mayr, Heinrich. Die Waldungen von Nordamerika 324. Miinchen. 
1890. 
¢ Sargent, C. 8. Silva of North America 10:134. 1896. 
§ Harkness & Moore. Cat. of Pacific Coast fungi 12. (Read before the 
Cal. Acad. of Sciences, Feb. 2, 1880). 
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