184 PATHOLOGY [BoT. Absts., Vol. VII, 



1238. Macrum, C. a. Combined bordeaux oil emulsion spray. Better Fruit 14^:9, 39. 

 1920.— Directions are given for making a combination spray solution by the addition to each 

 200 gallons of 1.5 per cent Bordeaux mixture (6-6-50) of 1^ pounds glue and 12 gallons oil 

 emulsion. — A. E. Murneek. 



1239. Maheux, Georges. Spraying to increase potato production. Ann. Rept. Quebec 

 Soc. Protection of Plants 12:43-46. 1920. — Results of potato spraying on sixty experi- 

 mental plots in forty countries are given. The yield for 1919 was 50 per cent higher in plots 

 sprayed four times than the check plot, and the net profit $30.00 per acre more. — B. T. 

 Dickson. 



1240. Martin, W. H. The relation of sulfur to soil acidity and to the control of potato 

 scab. Soil Sci. 9: 393-409. 1920. — In the experiments reported, five types of soil and two 

 varieties of potatoes were used. It was found that when sulphur was added to the soils the 

 decrease in scab corresponded to the increase of soil acidity as measured by the hydrogen-ion 

 concentration. The increase in acidity depended not only upon the amount of sulphur 

 added, but upon the percentage of sulphur which was oxidized. Where the hydrogen-ion 

 concentration of water extracts of the soil was Ph 5.8 or less before sulphur was applied, 300 

 to 500 pounds per acre gave approximately as good control as heavier applications. Where 

 the initial hydrogen-ion concentration exceeded 6.0 heavier applications (600-1200 pounds) 

 gave best control. — Dorothy Wilson. 



1241. McCuBBiN, W. A. The seed potato question. Seed World 8^: 24-25. 1920. 



1242. Newell, W. Citrus canker eradication in Florida. Monthly Bull. California State 

 Commission Hort. 8: 394-395. 1919. — The rapid spread of the citrus canker disease, in Florida 

 after 1912, when it was first observed by Dr. E. W. Berger is noted. Through the aid of 

 the state appropriations, however, work was conducted from 1912 to 1919 which practically 

 eradicated all signs of the disease. — E. L. Overholser. 



1243. Nowell, W. Red ring disease of coco-nuts. Agric. News [Barbados] 19: 222. 

 1920. — A method for the disposal of nematode-infested material is given. It consists in dig- 

 ging up the palm by the roots and sawing the trunk into 3-foot lengths over the pit formed 

 by the digging. Each length is then split longitudinally into about 6 pieces, and the whole 

 lot of material, including leaves, sawdust, etc., is placed in the pit over some brushwood in 

 the manner in which it is usual to place material for burning charcoal. The heap is then set 

 on fire and left to burn slowly under a covering of earth until all has been burnt to ashes. 

 The method is somewhat expensive, but the results obtained justify its employment. — 

 J. S. Dash. 



1244. Pethybridge, F. R. Potato spraying trials in the Cambridge Fens, 1919. Jour. 

 Ministry Agric. Great Britain 27:282-286. 1920.— Results are given from some potato- 

 spraying trials conducted during 1919 in which 1 and 2 per cent Bordeaux and Burgundy 

 mixtures were used at the rates of 85 and 200 gallons per acre. In all cases some scorching 

 of the foliage was obtained, and in a few cases it was severe. The weather was hot and dry 

 during a part of the season, and this was said to be the cause of the scorching. The yields 

 were less in the sprayed than in the unsprayed plots. — M. B. McKay. 



1245. PiPAL, F. J. The barberry and its relation to the stem rust of wheat in Indiana. 

 Proc. Indiana Acad. Sci. 1918: 63-70. 2 fig. 1920.— The author discusses briefly the his- 

 tory of Berberis vulgaris in its relation to wheat rust and cities 13 specific cases of rust out- 

 break investigated during the summer of 1917. — F. C. Anderson. 



1246. Regan, W. S. The destruction of Ribes by chemical means. American Plant Pest 

 Committee Bull. 4: 12. 1920.— Dip oil, containing 25 per cent cresol, sprayed on tops or 

 crown of bushy species kills in the majority of cases. Dilutions of dip oil with fuel oil, 36.3 

 degrees Beaum^, at the rate of 1 to 5 and 1 to 8 is advised for areas of skunk currant {Ribes 



