SPHAEROTHECA 149 



fined to the tips of the shoots of the year. The bark of 

 older branches cannot be infected. As already stated, many 

 winter-fruits fall to the ground during the autumn, these 

 remain lying on the ground, germinate the following spring, 

 and infect the bushes. The above condition of things sug- 

 gests pruning early in the autumn. All prunings should be 

 placed at once in some receptacle and burned, and not thrown 

 on the ground. During a late, mild autumn there is the 

 chance of new growth appearing as the result of early 

 pruning, and it is most important that such young growth 

 should not become infected, although the risk is not great, as 

 I have never once seen winter-fruit produced on mycelium 

 developed late in the autumn. To prevent the risk of autumn 

 infection the bushes should be sprayed with potassium 

 sulphide immediately after pruning, and again at a later date 

 if new growth appears. If the ground is turned over during 

 the winter, fallen winter-fruit will be buried. Not later than 

 the middle of January thoroughly drench all bushes that have 

 been diseased with the following solution : 2 lb. sulphate of 

 copper, h lb. of good quicklime, and thirty gallons of water ; 

 this is prepared after the manner of Bordeaux mixture. This 

 treatment must be applied before the buds begin to swell, 

 otherwise the foliage will be injured. 



In the spring when the leaf-buds begin to open, spray with 

 a solution of potassium sulphide (liver of sulphur), 1 lb. in 

 forty-eight gallons of water ; afterwards when the leaves are 

 expanded increase the strength of the solution to 1 lb. in 

 thirty-two gallons of water. From the middle of May to the 

 end of June is a critical time, as the winter-spores germinate 

 about this time, and start the infection for the season, hence 

 if the mildew is kept well in hand at the start an epidemic is 

 prevented. 



American gooseberry mildew has also been found on 

 red-currant bushes, and it may possibly also pass on to 

 black-currants and raspberries. 



A more detailed account of preventive methods is given in 

 the leaflet entitled, American Gooseberry Mildew, which can 

 be procured free of cost on application to the Secretary, 

 Board of Agriculture and Fisheries, 8 Whitehall Place, 

 London, S.W. 



Eriksson, Journ. R. Hort. Soc, 34, p. 469 (1909). 

 Salmon, Report on Economic Mycology, Wye College (1908). 



