650 EXPERIMENT STATION EECORD. [Vol.38 



A spot disease of apples, G. T. Spinks {Univ. Bristol, Ann. Rpt. Agr. and 

 Hort. Research Sta., 1916, pp. 27, 28; Jour. Bath and West and South. 

 Counties Soc, 5. ser., 11 (1916-11), pp. 155-151).— K study of the spot disease 

 of apples, which was prevalent during the winters of 1913 and 1914, and again 

 on some varieties during the winters of 1915 and 1916, has yielded some in- 

 formation regarding the spots, which look alike during the earlier stages, but 

 may later show differences in growth rate, color, and firmness or softness. 

 They may be caused by various fungi which enter through the so-called lenticel 

 some time before a spot appears, so that the actual time of entry is not known. 

 The spot grows rapidly as ripeness approaches. November and December ap- 

 ples, as a rule, can be affected only through points of injury- 



A gumm.osis of apricot, V. Peglion {Atti R. Accad. Lincei, Rend. CI. Sd. 

 Fis., Mat. e Nat, 5. ser., 26 (1911), I, No. 12, pp. 631-6J,1).—An apricot gum- 

 mosis is described which is said to be due to a Sclerotinia, probably S. laxa, 

 highly specialized in regard to apricot. It appears first during the period of 

 blooming, attacking the floral buds, branches, and trunk, and remaining in the 

 mummied fruit which may hang on the trees. 



Observations on pear blight in Illinois, F. L. Stevens, W. A. Ruth, G. L. 

 Peltier, and J. R. Maxloch (Trans. III. Hort. Soc, n. ser., 50 (1916), pp. 216- 

 221). — It is stated that conditions in central and southern Illinois favor severe 

 outbreaks of pear blight It is thought that the use of trees propagated on 

 the more resistant Japanese stock may prove to be of practical value for 

 Illinois growers, the grafts being made preferably on the larger limbs to avoid 

 body cankers. 



Apple blight was especially severe in southern Illinois in 1914. A study was 

 made in 1915 of the disease on 10-year-old pear trees and of control measures 

 at Savoy, about 1,000 buds being treated with water suspensions of bacilli 

 applied with a camel's-hair brush, half of these being covered immediately 

 with wet cotton to prevent drying out. No significant difference in degree of 

 infection developed between the treated and the untreated lots. Infections 

 through rapidly growing shoots, especially water sprouts, were numerous during 

 portions of the summer following wet weather in 1915, recent infections being 

 seen as late as August 4. Insect agency appears to be important. 



In the early spring of 1916 a few holdover cankers were observed on trunks 

 and larger limbs, giving abundant infective material and spreading the disease 

 throughout the orchard. Kieffer pear trees appeared to be more resistant 

 than Garber, as regards pear blight. No exuding cankers were observed after 

 the pears had bloomed. 



Bordeaux mixture applied just as the first flowers were about to bloom 

 controlled completely the blossom infection on Kieffer pear trees and did not 

 interfere with the setting of the fruit. Lime-sulphur spraying, started later, 

 was not quite so effective. 



A root rot of black currants, G. T. Spinks (Univ. Bristol, Ann. Rpt. Agr. 

 and Hort. Research Sta., 1916, pp. 29, SO; Jour. Bath and West and South. 

 Counties Soc, 5. ser., 11 (1916-11), pp. 151, 158). — Observations were made on 

 a 4-year-old plantation of black currants, located on an old orchard site, in 

 which several of the bushes appeared to be dead or dying in 1915 and 1916. 

 A fungus appears to enter the plant near the crown or at the point where 

 the main roots divide and then spread downward to the smaller roots. The 

 fungus has not yet been identified, but is suspected to be of the Armillaria 

 type. Young apple trees on similar areas are attacked apparently by the same 

 fungus, which has not yet yielded any fructifications. 



"Reversion" of black currants, A. H. Lees (Univ. Bristol, Ann. Rpt. Agr. 

 and Hort. Research Sta., 1916, pp. Sl-S^; Jour. Bath and West and South. 



