658 EXPERIMEl^T STATION RECORD. [Vol. 41 



these form the chief reliance during the spring when the best progress can be 

 made. Details are given of treatments employing these sprays in this area. 

 The necessity is emphasized of covering every part of leaves and twigs, with 

 special attention to the terminals. For this purpose, pressures of 200 to 250 

 lbs. are recommended to be employed in connection with eddycliamber or 

 whirlpool nozzles of the driving mist type. 



Apple scab and its control, J. W. Eastham {Canad. Hort., 41 (1918), No. 11, 

 pp. 253, 254, flff- 1)- — Outlining recent conditions and experiences regarding 

 apple scab in portions of British Columbia, the author outlines recomnfenda- 

 tions based on the results now available of worli done during the two previous 

 years. The chief defense relied upon as regards apple scab is timely and 

 thorough spraying with lime-sulphur, which is said to have almost entirely 

 superseded Bordeaux mixture for this purpose. Suitable concentrations em- 

 ployed are 1 : 30 for the dormant, 1 : 35 or 1 : 40 for the pinli, and 1 : 40 for any 

 of the latter sprays. The effects on the apple crop of lime-sulphur are not 

 yet fully determined. 



A new and effective disinfectant for pear blight, F. C. Reimeb (Better 

 Fruit, IS {1919), No. 10, pp. 24-27). — This contains information which has been 

 noted from another source (E. S. R., 41, p. 452). 



It is stated that tests on several pear varieties carried out with formalde- 

 hyde tend to show that the 10 per cent solution (one part of commercial 

 fornfaldehyde to nine parts of water) can be safely recommended for both 

 wounds and tools in connection with blight worli during the fall and winter 

 months. Cyanid of mercury was perfectly effective. A test is described as 

 carried out with a solution of the pure cyanid in distilled water prepared 

 fresh every day, carried in glass receptacles, and applied with a clean paint 

 brush, two drops of the blight culture ooze having been applied to each wound 

 in order to constitute a severe test. 



Experiments are in progress with commercial mercury cyanid tablets com- 

 monly found on the market to determine their value in this connection. 



June drop and its relation to the weather, C. A. Jensen {Cal. Citrogr., S 

 (1918), No. 11, pp. 255, 277, figs. 5). — This is a discussion of observations on 

 June drop of the navel orange in its alleged relation to weather (charts covering 

 June of 1917 and 1918 being given), and to other possible factors, no one or 

 combination of which appears sufQcient to explain fully its occurrence. 



Psorosis (scaly bark) of orange trees in California. H. S. Fawcett (Cal. 

 Citrogr., 4 {1919), No. 5, pp. 107, ISS, 1S9, figs. 5).— -The statements here noted 

 are understood to be tentative, as this disease is still under investigation at the 

 California citrus substation. The disease is discussed as to its several stages, 

 favoring conditions, and appropriate treatments. 



On the life history of the rose blotch fungus, N, L. Alcock {Roy. Bot. 

 Oard. Keto, Bui. Misc. Inform., No. 6 {1918), pp. 19S-197, pi. 1, figs. 2; Oard. 

 Chron., 3. ser., 65 {1919), No. 1671, p. 2). — A descriptive discussion is given of 

 the rose disease Actinonema rosce as regards the effects on the wood, with an 

 account of the survival of the winter stage, varieties attacked, and control 

 measures. The most effective of these consisted of 90 parts sulphur and 10 

 parts lead arsenate. Another almost as effective was a 5 : 5 : 50 Bordeaux 

 mixture. 



Fomes lucidus as a parasite of trees, W. Nowell {Agr. Netcs [Barl)ados'\, 

 17 {1918), No. 412, p. 46).— Plants named as subject to attack by F. {Poly- 

 porus) lucidus, usually at the center, include lime trees, Pithecolobium satnan, 

 P. unguis cati, C<Bsalpinia coriaria, and species of Acacia. 



