654 EXPERIMENT STATION KECOBD. 



previously considered ; and that threads of summer spores are dependent mainly, 

 if not wholly, upon moisture conditions for their development. 



The chestnut bark disease in Massachusetts, A. H. Graves (A 6s. in Phy- 

 topathology, 2 (1912), No. 2, p. 99). — ^The distribution of this disease in Massa- 

 chusetts is traced, and the author states that it would probably be practicable 

 for the State to adopt control measures in the northern and eastern parts. 

 Coppice was found to be no more susceptible than seedlings, but burned areas 

 are more apt to be infected than those untouched by fire. The best time for 

 locating the chestnut bark disease is said to be during the month of August. 



Summer and fall observations on the growth of the chestnut bark disease 

 in Pennsylvania, Caroline Rumbold (Ahs. in Phytopathology, 2 {1912), No. 2, 

 p. 100). — The results of observations on the fungus extending from July to 

 winter are given. 



During the summer period the rate of growth of mycelium and production of 

 spores is said to be affected principally by moisture, and this period lasts until 

 the latter part of December. During the transition period the pustules darken 

 in color, often fall off, the mycelium disappears, and the pycnidia become 

 sterile. Specimens collected on the first of December in different parts of the 

 State showed perithecia with ascospores. 



Preliminary notes on a twig blight of Quercus prinus, Della Ingram 

 (Ahs. in Phytopathology, 2 (1912), No. 2, pp. 96, 97). — A disease of the chest- 

 nut oak which was noted in the spring and summer of 1911 is described. The 

 range of the disease has not been definitely determined, but it has been reported 

 from Connecticut and from various points in Virginia, Maryland, and Pennsyl- 

 vania. 



When viewed at a distance the diseased trees have the appearance of having 

 been attacked by fire blight, the branches and leaves having the brown, blighted 

 appearance characteristic of that disease. The fungus Dothiorella quercina has 

 been found associated with the disease and is believed to be the cause of the 

 trouble. 



Tannic acid as protection for oak wood against dry rot, C. Wehmer (Mycol. 

 Centhl., 1 (1912), Nos. 5, pp. 138-148, figs. 6; 6, pp. 166-17Jf) .—Fursuant to pre- 

 vious studies (E. S. R., 26, pp. 551, 752; 27, p. 355), the author experimented on 

 the growth of Merulius lacrymans as affected by tannic and gallic acids in 

 various cultures. Solutions of from 0.5 to 5 per cent strength were found to 

 hinder or stop growth in nearly all solutions. Pine wood, ordinarily attacked 

 and destroyed by this fungus, was protected by a 1 to 2 per cent solution. Prac- 

 tical applications are suggested. 



Bacterial black spot of walnut, L. Rodway (Agr. Gaz. Tasmania, 20 (1912) ^ 

 No. 3, pp. 85, 86, fig. 1; abs. in Jour. Dept. Agr. So. Aust., 15 (1912), No. 10, p. 

 991). — The author notes the appearance of this disease in many of the walnut 

 trees about Hobart. It appears first as small black spots on the surface of both 

 nut and leaf. The disease spreads rapidly, involving finally all parts of both 

 nut and leaf, weakening the tree so that death results in a few years. It 

 appears to start on the surface from new infection each year, the parasitical 

 bacterid gradually penetrating deeper layers of cells as the vitality of the tree 

 becomes reduced by the disease. The trunk, however, does not seem to be 

 attacked directly. It is thought that consistent spraying with Bordeaux mix- 

 ture will greatly reduce the attack. Removal of infected parts in early stages 

 of the disease is also recommended. 



Peridermium cedri as a destructive fungus, R. S. Troup (Indian Forester, 

 38 (1912), No. 5, pp. 222, 223, pi. 1). — ^This fungus, which produces the charac- 

 teristic witches' brooms on Deodar trees in certain parts of the Himalayas 



