BOUILLIE BORDELAISE. 255 



this disease is overcome by several sprayings, the first of which is 

 given before the opening of the buds. According to Weiss by a spray- 

 ing before and after fiovvering. This treatment is better than by 

 potassium sulphide (Duggar). 



Gloeosporium Bibis, Mont, and Desm. (cunant leaf spot). — Weiss 

 advises to overcome this disease preventively by two sprayings, the 

 first before the opening of the buds, the second after flowering. 



Gloeosporium curvatum, Oadem. (disease of the leaves of the goose- 

 berry). — Sorauer recommends the preceding preventive treatment 

 by bouillie bordelaise. 



Gloeosporium Juglandis, Mont, (walnut leaf disease). — Injurious 

 to young plantations, it is combated preventively by spraying with 

 bouillie bordelaise (Sorauer). 



Gloeosporium venetum, Speg. (raspberry spot, in America). — Selby 

 and Green recommend preventive treatment with bouillie bordelaise. 



Gloeosporium fr utigenum, Berk, (bitter rot of the apple). — Garman 

 and Stinson overcome this disease by four sprayings, the first before 

 the fall of the petals, and the three others at fifteen days' interval. 



Gloeosporium phomoides, Sacc. (anthracnosis of tomato, in America). 

 — Halsted advises spraying with bouillie bordelaise. 



Gloeosporium macropus, Sacc. (orchid disease, especially the 

 varieties Laelia and Cattleya). — Mangin advises a 2 per cent bouillie 

 bordelaise. 



Amongst the great number of Phyllosticta, Pers., which are char- 

 acterized by the small round spots which they form on their nurse 

 plants, only the following have been tried with bouillie bordelaise : — 



Phyllosticta sphcErojJsidea, Ell. et Ev. (horse chestnut {Msculus 

 Hippocastanum] leaf disease). — Fairchild has used bouillie bordelaise 

 as a preventive with success. 



Phyllosticta Pirina, Sacc. (pear-tree leaf spots). — Weiss has over- 

 come this disease with bouillie bordelaise. 



Fusicladium Pirinum, Fuckel (pear scab) ; Fusicladium dentriti- 

 cum, Fuckel (apple scab). — It is very important for orchards to pre- 

 vent this disease. The knowledge of the evolution of these fungi 

 enables it to be overcome preventively. It is above all necessary to 

 prevent tne transmission of the disease from one year to another by 

 destroying the holed branches, the spotted leaves and fruit, on which 

 are formed the winter spores which infest the young organs of the 

 new vegetation in the spring. This wise precaution is far from 

 sufficient. The whole tree must be disinfected chemically by cover- 

 ing all its pans with a concentrated solution of green vitriol, acidu- 

 lated by sulphuric acid, say with a concentrated bouillie bordelaise 

 containing 4-5 per cent of blue vitriol and as much lime. Eicaud 

 was the first, in 1866, to treat fruit trees with bouillie bordelaise. 

 He advised to treat the walls and the trellises against which the 

 trees are nailed up in the same way. It is almost indispensable to 

 spray the soil copiously around the tree in autumn and spring, so as 

 to disinfect the surface layer of soil, on which numerous germs of 

 cryptogamic disease always fall with the leaves. A soil containing 4 

 per cent of bouillie bordelaise in no way affects the germination of 



