m 



and 1 lb. freshly slaked lime (the poisons being in dust form and 

 diluted in 25 U.S. gals, water in each case). The first application 

 should be made when the potato plants are six inches high, and 

 repeated at intervals of from 10 to 14 days ; two applications usually 

 suffice ; 50 gals, of spray cover an acre when the plants are small, but 

 when they are larger 80-100 gals, will be required. Hand-pickmg 

 and jarring for small plots are also described. 



Le Soeuf (W. H. D.), The Value of the Ihis.— American Forestry, 

 Washington, D.C., xxvi, no. 319, July 1920, pp. 410-411. 



The ibis is very useful to agriculture in Australia. It has been 

 calculated that a colony of these birds that nests in a swamp in New 

 South Wales, numbermg 200,000 individuals, accounts for as many 

 as 482 millions of grasshoppers a day as wtII as other insects. Many 

 of the slower flying hawks feed largely on insects, and cockatoos also 

 prey upon grasshoppers by digging up and devouring their egg-clusters. 



Caesar (L.). Insects and Diseases in Cherry Orchards. — Canadian 

 Horticulturist, Toronto, xliii, no. 7, July 1920, pp. 191-192. 



The chief insects attacking cherries are : black Aphids [Myzus 

 cerasi], which as a rule only attack sweet cherries ; plum curculio 

 [Conotrachelus nenuphar], responsible for the so called " stinging " of 

 cherries ; and cherry fruit-flies [Rhagoletis cingulata and R. fausta], 

 which are very destructive in some orchards, though others are un- 

 harmed [R.A.E., A, iii, 293]. 



Three sprayings are usually enough to control both insects and 

 diseases. The first should be applied just before the buds break and 

 should consist of 1 gal. lime-sulphur to 7 or 8 gals, water, with the 

 addition of Black-leaf 40 according to the directions for black Aphids. 

 For sour cherries the Black-leaf 40 is omitted, and the spray should be 

 only about a quarter as- strong, or Bordeaux mixture (4:6: 40) may 

 be used. The second spray, applied as soon as the fruit is formed and 

 nearly free from the remnants of the blossom, should consist of 

 Bordeaux mixture of the above strength or a little weaker, with the 

 addition of 1 lb. calcium arsenate, or 1| lb. lead arsenate (powder). 

 Lime-sulphur is not quite equal to Bordeaux mixture as an alternative. 

 For the third spray, applied as the earliest varieties are begmning to 

 colour, the same mixture should be used as for the second. It is hoped 

 to find a liquid spray that will have the same effect as the sulphur dust, 

 which has been shown to be beneficial just before the cherries are picked 

 to prevent brown rot without staining the fruit as liquid sprays usually 

 do. 



Fisher (D. F.). Apple Powdery Mildew and its Control in the Arid 

 Regions of the Pacific North-west. — U.S. Dept. Agric, Washington, 

 D. C, Bull., 712, 29th October 1918, 28 pp., 3 plates, 2 figs. 

 [Received 27th July 1920.] 



The powdery mildew disease of apples is caused by the fungus, 

 Podosphaera leucotricha, which passes the winter in mycelial form in 

 dormant buds. It is disseminated by the wind and possibly to some 

 extent by insects. 



The beetles, Psyllobora borealis, Casey, Pentaria nubilia, Lee, and 

 Anthicus nitidulus, Lee, have been found feeding on this mildew. 



