DISEASES OF PL-^NTS. 247 



The author gives a list of the varieties of apples and pears that were obser\ ed 

 to be susceptible or resistant to each of these fungi. 



The red color of the fruit, and the scab of apples and pears, J. Eriksson 

 (Ztschr. Pflanzenkranlc, 21 (1911), Xo. 3, pp. 129-131, flffs. 2).— The author 

 takes issue vs^ith E. Voges, vpho in a recent article (E. S. R., 24, p. 450) claimed 

 that red-skinned apples are more resistant to scab than other kinds. He cites 

 examples of red and yellow skinned varieties of both apples and pears which 

 were badly attacked by this disease, not only the fruit but even the leaves being 

 badly injured in some instances. 



Black spot or apple scab, E. S. Salmon (Jour. Southeast. Agr. Col. ^V]|(', 

 1909, No. 18, pp. 261-210, pis. S).— The author gives the history of an attack by 

 apple scab in an orchard whore for several years the disease was neglected 

 until all the fruit of certain susceptible varieties was ruined, yet which was 

 practically controlled by judicious spraying with a 4 : 100 mixture of copper sul- 

 phate in February, followed by two or three sprayings with Bordeaux mixture. 



Cooperative spraying at the Cove for apple scab (Greg. Agr. Col. Bui., 

 1. SCI'., 1911. \o. .'/.S, /*. 29). — The results iire reijoried of exiierinients undertaken 

 to determine the most effective time to spray with lime-sulphur mixtures for 

 apple scab under the local climatic conditions. Fourteen-year-old trees of the 

 Mammoth Black Twig, which is a very susceptible variety, a 1:15 solution of 

 lime-sulphur mixture, and a hand pump with a pressure ranging from 100 to 125 

 pounds were used in these tests. 



The results indicate that the proi:)er time to spray under the local conditions 

 is when the blossoms are showing pink, which occurs about the 1st of May, 

 and that only the one application is necessary, as later sprayings showed no 

 evident advantage over the first in controlling the scab. 



Tumors on apple trees, P. Sorauer {Ztschr. Pflanzenkranlc., 21 (1911), No. 

 1-2, pp. 21-36, pis. 2). — The author claims that the twig swellings or tumors 

 often seen at the base of the side twigs on apple and pear trees are not due 

 primarily to capsids (Orthotylus nassatus), as is usually supposed, but are ini- 

 tiated by frost injuries to the inner cells of the shoot, which later are attacked 

 by the capsids. 



New fig^ anthracnose (colletotrichose), F. L. Stevens and J. G. Hall (North 

 Carolina Sta. Rpt. 1909, pp. 86-89, figs. 3). — Previously noted in part from 

 another source (E. S. R.. 21, p. 447). 



Pruning and the inoculation of the olive knot bacteria, L. Savastano (Boh 

 Ardor. Itah, 6 (1910), No. 1, pp. 30-33). — From observations and experiments 

 the author concludes that the infection of healthy olive trees with the olive 

 knot organism by means of priming tools rarely occurs. Nevertheless, it is sug- 

 gested that the tools while being used should be sterilized. 



American gooseberry mildew, T. H. Middleton (Bd. Agr. and Fisheries 

 [London], Intel. Div.. Ami. Rpt. Proc. 1909-10, pp. 5-25). — In a report to the 

 secretary of the Board of Agriculture and Fisheries on the Destructive Insects 

 and Pest Acts of 1877 and 1907 the present status of the American gooseberry 

 mildew in England is discussed, including regions infected, severity of infesta- 

 tion, susceptibility of different varietes of gooseberres, sources of infection, 

 and remedies. 



Nine districts are named where the disease is thoroughly established or is 

 known to exist. Instances are recorded of infection from returned empty bas- 

 kets which had contained diseased fruit, from infected clothes and boots of 

 workmen, from wind-carried spores, from the introduction of diseased plants, 

 and from reinfection from winter spores dropping on the soil. 



The best remedy found for controlling the disease was late fall or early win- 

 ter priming, in which all old wood, unnecessary branches, suckers, and the tips 



