436 DISEASES OF ECONOMIC PLANTS 



the next is not the normal red, but is somewhat browned, 

 and the holes themselves are coated with a brilliant white 

 lining. The holes, partially filled with a velvety reddish- 

 yellow mycelium, may be from 4-9 cm. long. The pore- 

 bearing sporophore is hard and woody, rough above, later 

 fissured, yellow-brown at the margin, later deep brown. 

 The pore layer is yellow to brown. 



Red rot, pecky cedar {Polyporus carnmis Nees). — Though 

 more common than white rot, this has been found in 

 Missouri, Arkansas, Kentucky, Tennessee, \'irginia. New 

 York, and Mississippi. 



The wood is full of pockets of browm, brittle wood, vary- 

 ing from a centimeter to a meter or so in length. The 

 sporophore, formed in the cavities under dead branches, is 

 from 0.5-35 cm. in length by 1 cm. wide. The pore-bearing 

 layer is flesh colored. 



These two diseases of the cedar taken together have been 

 estimated to cause 60 per cent loss in some localities. 

 Since they are caused by wound parasites, the removal of 

 diseased trees and the destruction of sporophores is 

 recommended. 



CHESTNUT 



Bark disease^ (Diaporthe parasitica Murrill). — First 

 noted in 1904 by Murrill in New York, this disease is 

 now known in New York, New Jersey, Delaware, Con- 

 necticut, Rhode Island, Maryland, and Virginia, and is 

 rapidly spreading in every direction. In Brooklyn 16,695 

 trees were killed on 350 acres, and the loss in and about 



' Metcalf, H., and CoUina, J. F., U.S. Dept. Agr. Bur. Plant Indus. Bui. 

 141. 



