CAT ALP A DISEASES 127 



they are broken off, a hole is left in the trunk which serves as 

 an excellent infection court. The mycelium progresses rapidly 

 in the wood. For further details concerning the life history 

 and control of the wood-rotting fungi, see page 64. 



Control. 



As a means of preventing loss from this rot in plantations, 

 it is advised that the lower limbs should be pruned off and the 

 wounds treated with a dressing. Directions for these opera- 

 tions will be found on page 345. 



Rbperences 



Schrenk, Hermann von. II Diseases of the hardy catalpa. In The 



hardy catalpa. U. S. Dept. Agr. Bur. Forestry Bui. 37 : 49-58, 



pis. 23-30, figs. 1-2. 1902. 

 Stevens, Neil E. Polystictus versicolor as a wound parasite of 



catalpa. Mycologia 4 : 263-270, pis. 74-75. 1912. 

 Stevens, Neil E. Wood rots of the hardy catalpa. Phytopathology 



2:114^119, pi. 10. 1912. 



Brown Butt-Rot 



Caused by Polyporus (Poria) catalpce Schrenk 



The heartwood and sapwood of the base of the hardy catalpa 

 is sometimes affected by this brownish wood-rot. The wood 

 becomes reddish brown and crumbly. It cracks along the 

 annual rings and at times across them, leaving spaces which 

 are filled by felts of mycelium. The fruiting-bodies of the 

 causal fungus are described as thin sheets of mycelium which 

 lie closely appressed to the diseased wood. The surface is 

 covered with small pores which are the openings of perpen- 

 dicular tubes in which the spores are borne. The fruiting- 

 structiu-es are at first whitish, but later become yellowish and 

 brown. This fungus enters the tree through the branch wounds 

 in the same way as described under the yellowish wood-rot 



