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from growing out to their full size. At 

 the white powdery stage the disease is 

 very infectious, for the powder consists of 

 chains of spores which are blown away in 

 the wind and carried considerable dis- 

 tances, thus giving rise to outbreaks in 

 plantations and gardens where it has not 

 previously occurred. A diseased planta- 

 tion thus serves as a sourse of infection 

 for others in the neighbourhood. 



As the fungus assumes the brown 

 colour it develops fructification of another 

 form which may just be seen with the 

 naked eye as minute black specks em- 

 bedded in the brown felted layer. In the 

 following spring these fructifications 

 burst and, from them, 'spores are forcibly 

 ejected into the air; if these spores reach 

 the young gooseberry shoots or fruit, in- 

 fection again breaks out. 



Control measures consist of (1) remov- 

 ing and burning infected shoots bearing 

 the over-wintering fructifications; (2) 

 spraying the bushes with a fungicide 

 which will protect the berries and young 

 shoots. The most useful spray fluid, at 

 present known, for the latter purpose is 

 the lime sulphur solution ; where there has 

 been a severe attack during the previous 

 season the first application should be 

 made soon after the leaves unfold, and 

 later spraying should be carried out at 

 intervals of about ten days or a fortnight. 

 On some varieties the lime-sulphur can 

 be used at full summer strength (sp. gr. 

 1.01), e.g., Cousin's Seedling and May 

 Duke; on other e.g.. Berry's Early, Crown 

 Bob, and Lancashire Lad, the solution 

 should be used at half that strength 

 (sp. gr. 1.005), while Yellow Eough and 

 Valentine's Seedling are varieties so 

 susceptible to spray injury that sulphur 

 washes should not be used on them. 



One disadvantage to the use of lime- 

 sulphur spray is the whitish deposit 

 which is left on the berries causing them 

 to be disfigured. This is obviated by 

 replacing the lime sulphur by the am- 

 monium polysulphide and soft soap wash 

 as the fruit approaches maturity; the 

 latter is an effective fungicide against the 

 mildew when in the white powdery stage 

 and leaves no visible deposit on the leaves 

 or fruit. The concentrated solution of 

 ammonium polysulphide as supplied by 

 the manufacturers should be so diluted 



that the wash contains 0.11 per cent, poly- 

 sulphide sulphur and instructions for 

 obtaining such a dilution should be sup- 

 plied with the concentrate. 



The European Gooseberry Mildew, 

 M icrosphaerd (jrossiilarhe, also infects 

 the foliage of the gooseberry, but as it 

 does not extend to the fruit it is far less 

 harmful than the American Gooseberry 

 Mildew. 



" Die-Back " of Gooseberry Bushes. 



Another disease of gooseberry bushes is 

 one which frequently kills the branches, 

 or even whole bushes, outright. Infection 

 often occurs on the main stem near the 

 ground level, and as the fungus extends 

 round the stem the bush is killed. The 

 young shoots, leaves, ■ flowers and fruit 

 are also points of attack. When the 

 leaves are infected they become grey or 

 whitish round their margins, and in a 

 severe attack fall off prematurely. 



The fungus, Botrylis ci/iercii (Sclero- 

 tiiiia FucheUaua), which causes the 

 disease is to be seen, particularly during 

 damp weather, on the surface of the affec- 

 ted parts as grey powdery tufts, which on 

 the fruit and flowers often coalesce to form 

 an almost continuous layer. These fruc- 

 tifications produce numerous spores which 

 are scattered by the wind and blown to 

 other bushes. 



Affected bushes should be uprooted and 

 burnt; if single branches are killed they 

 should be pruned off and similarly des- 

 troyed. As the fungus can continue to 

 grow on the branches and stems killed by 

 it, the prompt destruction by burning of 

 these is essential to the complete control 

 of the disease. Where the disease has 

 been prevalent during the preceding sea- 

 son, the bushes should be sprayed with 

 Bordeaux mixture, as soon as the fruit 

 has set, in order to prevent leaf infection. 



Cherry Leaf Scorch. 



The presence of this disease on cherry 

 trees is denoted by the characteristic 

 feature that on affected trees the leaves 

 which become infected do not fall in 

 autumn, but remain in a withered condi- 

 tion on the trees throughout the winter 

 until the leaves and flowers appear in the 

 following spring. The cherry leaf scorch 

 fungus, Gnomonia trytlarostovia, infects 



