204 MANUAL OF TREE DISEASES 



host for this species is Porteranthus (Gillenia) stipidains (Muhl.) 

 Britton. 



White B.\kk 



Caused by Cyanospora alhicedrcE Heald and Wolf 



This disease is common on the mountain juniper throughout 

 its range in Texas. White patches, either small or extensive, 

 occur on the bark of the young twigs and larger branches of 

 yoimg trees. The twigs are killed after the white areas have 

 encircled them. Many of the branches, or the entire tree, may 

 be killed in this manner. Shading seems to make the twigs and 

 branches more susceptible. Upon the whitened areas of the 

 bark nmnerous grayish pustules are formed, containing the 

 fruiting-bodies of the fungus. After the bark is decayed, the 

 pustules stand out prominently. Projecting from the upper 

 surface of the grayish pustules are one to three short beaks which 

 represent the openings of the fruiting-bodies buried in the pus- 

 tules. Ascospores are formed in these fruiting-bodies and ooze 

 out through the openings during moist weather. 



Reference 



Heald, F. D., and Wolf, F. A. The whitening of the mountain cedar, 

 Sabina sabinoides (H. B. K.) Small. Mycologia 2 : 205-212, 

 pi. 31, figs. 1-3. 1910. 



Brown Pocket He.uitwood-Rot 



Caused by Fames roseiis Fries 



This heartwood-rot was first described as a disease of juniper, 

 but recently has been foimd commonly in fir, larch, spruce, pine, 

 hemlock and occasionally in arbor-vitse, birch and maple, over 

 practically the entire United States wherever conifers are im- 

 portant forest-trees. It may be confused in some trees with the 

 red-brown root- and butt-rot caused by Polyporus Schioeinitzii (see 

 page 294), unless the fruiting-bodies are present to identify it. 



