544 EXPERIMENT STATION RECOED. 



mettiods, comparison between direct and steam-heated stills, the supply of 

 longleaf pine for turpentine operations, possibilities of western pines as a 

 source of naval stores, special problems investigated, Arizona and California 

 western yellow pine, suggestions for specifications, packing naval stores, cost 

 estimates on a 20-crop turpentine operation, publications relating to the naval 

 stores industry, and patents relating to the naval stores industry. 



Kecords on the life of treated timber in the United States, H. F. Weiss 

 and C. H. Teesdale {Proc. Amer. Wood Preservers' Assoc, 11 (1915), pp. 501- 

 509). — ^A tabular compilation of data showing the life of treated timber in the 

 United States. Various records are given for cross-ties, piling, bridge timbers, 

 mine timbers, poles, posts, and paving blocks. 



. DISEASES OF PLANTS. 



Notes on plant diseases in Virg'inia observed in 1913 and 1914, H. S. Reed 

 and C. H. Crabill (Virginia Sta. Tech. Bui. 2 (1915), pp. 31-58, figs. 17).— 

 Descriptions are given of diseases observed on alfalfa, apple, bean, maple, 

 peach, plum, and potato. 



Among the alfalfa diseases of unusual occurrence the authors note yellow 

 top, a disease considered identical with that previously reported in New 

 York (E. S. R., 20, p. 846), and white spot, in which infected plants show 

 white semitranslucent spots on the leaves. Both of these diseases, the causes 

 of which are undetermined, may at times induce considerable injury. 



Among apple diseases the authors report the occurrence of blister canker, 

 collar blight, crown gall, and sunburn. In addition a number of unusual 

 troubles are described, the definite causes of which are unknown. Among 

 these are a form of tumor to which the name flap tumor is given. This dis- 

 ease is characterized by peculiar flap-like growths that are developed cover- 

 ing wounds due to various causes. A brief notice is given of punky pulp 

 of Ben Davis, in which the fruits are said to be smaller than normal, punky, 

 brittle, and entirely unfit for consumption. This trouble is believed to have 

 been due to the dry weather of 1914. Root rot of apple trees, which is said 

 to be causing considerable loss, is described, the disease being accompanied by 

 a white mycelium, but as yet no sporophores of the fungus have been found 

 present. A skin crack of the York Imperial apple is described, which is believed 

 to be due to physiological disturbances such as sudden increase of water 

 supply. In this trouble small sunken cracks appear in the skin of the fruit. 

 Usually the cracks are less than 2 mm. in length, but sometimes they are 

 larger and a number of them become confluent, giving the fruit a grayish scabby 

 appearance. Later a soft black rot, caused by Alternaria mali, attacks the 

 fruit through the tissue underneath the cracks. Another apple trouble, which 

 is called the York spot, is confined to the variety York Imperial. This in 

 the early stages resembles the disease commonly called Jonathan or Baldwin 

 spot, but later the fruit exhibits sunken, dark green spots, beneath which 

 the tissue is brown-walled, the areas infe^tted resembling the injury due to 

 hail. Later in the season badly infected fruits show soft rot, probably due 

 to saprophytic fungi. No organisms have been grown from the spots until 

 soft rots have set in. The cause of this disease has not been definitely 

 determined. 



A brief account is given of a thrombotic disease of silver maple, in which 

 the leaves turn yellow, growth is poor, and the trees become defoliated earlier 

 than usual. An examination of infected limbs showed that the wood was 

 streaked with green, resembling the condition described by Rankin as due to 

 Acrostalagmus sp. (E. S. R., 33, p. 249). 



