158 EXPERIMENT STATION RECORD, 



The blossom blight or blast attacks the young fruit about the time the blos- 

 soms fall. The iiriniary cause of the disease is believed to be either a general 

 lack of vigor of the vines or an exhausting of the fruiting power of the plants 

 by excessive stimulation and growth. This disease may be held in check by 

 the sanding of the bogs, a practice commonly followed in the East, or by cut- 

 ting and thinning the vines by the use of the knife rake. It is believed that 

 better attention to the water supply would also reduce the loss due to this 

 cause. 



The false blossom is i)robably due to a disturbance of the physiological func- 

 tions of the plant, brought about by abnormal conditions of growth and an 

 excessive amount of nitrogenous plant food. It is characterized by the produc- 

 tion of abnormal flowers, the sepals, petals, and stamens of which are fre- 

 quently changed into leaves or leaf-like bodies. The reduction of the water 

 supply, accompanied by i)runing of the vines and liberal sanding of the marshes, 

 it is believed will prevent loss from this cause. 



Some diseases of strawberries, F. Laibach (Arb. K. Biol. Anst. Land u. 

 Forsttc. 6 il'JOS), A'o. 7, ijp. 76-80, figs. 3). — The author describes diseases of 

 the strawberry caused by Marsonia potcntillw, Leptothyrium macrothecium, 

 and /.iitliiit fniffaria' n. sp. 



A pine disease {Bd. Agr. and Fisheries [London], Leaflet 199, pp. .3, flg. 1). — 

 A disease of pine trees is described which is due to the fungus Diplodia pinea. 

 The disease is confined to terminal shoots and is recognized by the yellowing 

 and subsequent shedding of the leaves, followed by the death of the shoots, 

 which die back for a distance of 6 to 10 in. The dead shoots are persistent, 

 and commencing with the year following infection furnish a crop of spores each 

 season which infect other shoots. Experiments conducted at Kew show that 

 within 2 months after infection the leaves become yellow and begin to twist 

 themselves, due to desiccation, and that at the expiration of 4 months all the 

 leaves have fallen and the shoot is dead. 



Inoculation experiments were carried on in which spores wei'e placed on 

 3-year-old plants of white pine, Scotch pine, spruce, silver fir, and larch. In 

 every instance where the surface of the young shoots was unbroken the spores 

 failed to infect the plant, but where the spores were placed on a drop of 

 moisture that extended from a minute puncture in the bark, they set up an 

 infection which resulted in a dense growth of mycelium, followed by yellowing 

 and falling of the leaves. Successful inoculations were made in the case of the 

 2 species of pine, but no infection occurred on spruce, fir, or larch. 



It is believed that the fungus infects the plants through the action of insects, 

 and this point is to be investigated further. 



In the case of nursery stock and young trees the removal of all dead shoots 

 would tend to check the spread of the disease to a considerable extent. 



A disease of pine twigs, L. Petri {Ann. Mycol., 5 {1901), A'o. ,'/, pp. 326-3.32, 

 pi. 1; abs. in Bot. Centbl., 101 {1908), No. 10, p. 2//S).— The author describes a 

 disease of young pine trees, in which the terminal branches are destroyed. The 

 cause of the disease is said to be Cijtosporella damnosa n. sp. and it resembles 

 in some respects a disease of firs due to Cytospora and one of hemlock caused 

 by Fusicoccum ahictinum. 



The fungus has been cultivated and inoculation experiments performed,- in 

 which it was found that the spores readily infected the young twigs where they 

 had become injured by any mechanical means. Where there was no previous 

 injury there seemed to be no infec-tion. 



Witches' brooms of Pinus sylvestris, K. MtJLLER {Naturiv. Wchnschr., 23 

 [1908), No. 9, pp. 13-'t-136, figs. 3). — A description is given of a number of 

 striking foi'ms of witches' brooms that have been observed occurring on P. syl- 



