144 EXPERIMENT STATION EECOED. 



Scolytus rugulosus as an agent in th.e spread of bacterial blight in pear 

 trees, D. H. Jones (Phytopathology, 1 {1911), No. 5, pp. 155-158, pis. 2). — In 

 previous publications (E. S. R., 23, pp. 49, 352) attention was called to tlie 

 probability of this beetle having an important part in the spread of bacterial 

 blight in pear orchards. Subsequent studies have confirmed this conclusion, 

 and the author found that practically every lesion on trunks and limbs of the 

 trees under observation had within it a boring beetle. It appears to be con- 

 clusively proved that 8. rugulosus is an active agent in the spread of bacterial 

 blight among pear trees, and means should be taken to destroy this insect. 



Peach leaf curl fungus, G. Quinn (Jour. Dcpt. Agr. So. Atist., 15 (1911), 

 No. 1, pp. 58-66, figs. 4)- — A. report is given of investigations in spraying peach 

 trees for the control of the peach leaf curl with Bordeaux mixture. Burgundy 

 mixture, Bordeaux paste, and copper sulphate solution. 



All of the treatments reduced the proportion of diseased leaves on the 

 trees. Two applications of Burgundy mixture or of Bordeaux paste com- 

 pletely protected the trees, while a few diseased leaves were found where trees 

 were sprayed with Bordeaux mixture or a single application of copper sul- 

 phate. In one experiment, however, with Bordeaux paste a large number of 

 diseased leaves were found. Dressing the soil about the trees with iron sul- 

 phate did not give beneficial results. 



The destruction of plum trees in the Rhine Provinces and the cherry 

 tree disease, G. LiisTNEB (Ber. K. Lchranst. Wein, Obst u. Oartenbau Oeisen- 

 heim, 1910, pp. 147-150). — During 1910 heavy precipitation caused a repoateH 

 overflow of the Rhine River, and from June 20 to July 31 the adjacent country 

 was submerged to a greater or less extent. This was followed in August by 

 bright sunshine. 



The leaves of plum trees were scorched and later died. Injury to maple trees 

 from the same cause is noted, and attention is called to the fact that Colchiciim 

 autumnale, which generally flowers in the fall of the year, did not bloom until 

 March, 1911, six months later than usual. 



The disease of cherry trees in the same region is commented upon, and it is 

 held to be due to unfavorable soil conditions. The author says that Valsa leu- 

 costoma is not the primary cause of the trouble, the fungus being able to attack 

 only those trees that have been weakened from some other condition. 



A bacterial gummosis of cherries, F. L. Griffin (Science, n. ser., 3Jf (1911), 

 No. 879, pp. 615, 616). — A description is given of a gummosis of cherry trees, for 

 which the author believes that he has found a specific cause. 



The disease is quite prevalent in Oregon upon cherry trees, and is thought to 

 be due to Pscudomonas cerasus n. sp. Its characters are contrasted with those 

 described for other bacterial diseases of cherries (E. S. R., 14, p. 458; 18, p. 

 947), but they are believed to be quite distinct. The author has isolated the 

 organism, inoculated trees from pure cultures, produced typical symptoms, and 

 reisolated the bacterium. 



Cherry trees weakened through gummosis fall easy prey to various sapro- 

 phytic fungi, Schizophylium commune and species of Polyporus and Polystictus 

 being the most common. 



It has been found by experience that top working resistant stocks will to a 

 great extent prevent the disease from appearing on the body or crotch of the 

 tree, but this eliminates the gummosis factor only from the trunks and not from 

 the fruit-bearing wood. 



Experiments in the control of the red spot disease of grapes, G. Lxjstner 

 (Ber. K. Lchranst. Wein, Obst u, Gartenbau Gcisenhei'm, 1910, pp. 175, 176). — 

 In continuation of previous notes (E. S. R., 24, p. 157), the author reports ex- 



