Current Literature. 245 



Under the first are discussed the various more common needle 

 diseases such as Lophodermiiim and Hypoderma. The incense 

 cedar rust, {Gymnosporangium bias d ale antim) , and the pine gall 

 fungus (Peridermium harknessii), are described at some length. 



Among the more important diseases of the second group dis- 

 cussed are the following : 



Fomes annosus, which is very destructive to trees in Europe 

 and Eastern United States, but which is as yet not dangerous in 

 California. Trametes pini, the ring scale fungus, which is the 

 cause of destructive diseases of mature and overmature conifers. 

 Fomes laricis, the chalky quinine fungus, which causes red heart- 

 rot in various valuable conifers, including the sugar pine. ^0/3;- 

 porus sulphiireus, the destructive sulphur fungus, most often 

 found on oak, chinquapin and red fir, but occurring also on 

 Douglas and white fir, and yellow and Jeffrey pine. Polyporus 

 aiiiarus, which in producing dry rot of incense cedar, causes enor- 

 mous damage on the Pacific Coast. Polyporus schzifeinitsii, one 

 of the most serious enemies of Douglas fir and which also occurs 

 on certain pines and on white fir. Fouies pinicola, the red-belt 

 Fomes, which is the commonest timber-destroying pore fungus in 

 California, attacking all the important conifers except incense 

 cedar, juniper, redwood and bigtree. Polyporus dryophilus, 

 which causes a destructive heartrot in living oaks. Fomes igni- 

 arius, the false tinder fungus, which is confined to the deciduous 

 trees and is especially common on willows, cottonwood and quak- 

 ing aspens, causing a white heartrot which sometimes extends into 

 the sapwood. Bchinodontmm tinctorum, the Indian paint fungus, 

 which is one of the most common wood-destroying fungi in Cali- 

 fornia, found almost exclusively on white fir, causing the char- 

 acteristic stringy brown rot. This is the fungus, the effect of 

 which has brought the white fir into great disfavor among the 

 lumbermen. ArmiUaria mellea, the honey fungus, which is one 

 of the most destructive root fungi of oaks and orchard trees. It 

 is not very common in our forest trees, but sometimes attacks 

 coniferous trees of all ages, often spreading through diseased 

 roots to roots of sound neighboring trees which it kills in a short 

 time. 



