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out none but healthy plants, and three or four ai)plications of Bordeaux 

 should be given early in the season. The first spraying should be applied 

 before the leaf buds open; the second just after the young canes appear 

 above ground; the third two weeks later; and the fourth just before the 

 flowers open. 



4. Strawberry Leaf Spot. 



(Mycosphaerella fragariae, Lindau.) 



The Strawberry Leaf Spot is present more or less in every plot of 

 strawberries, but only occasionally does it injure the crop to any extent. 

 Affected leaves show at first about blossoming time small purplish spots, 

 which soon enlarge and run together forming somewhat irregular areas. 



Fig. 2— (n) A leaf of strawberry afToctcd with leaf blight: (b) spore-bearing tuft of mycelium bursting through 

 the epidermis of the leaf: (c) summer spores arising from apex of a resting spore case: (d) summer spores 

 (conidia), one germinating: (e) section of a spore pustule ^spermogonium) produced in summer: (f) section of 

 resting or winter spore case (perithecium), found in tissues of old diseased leaves which have lain on the ground 

 over winter: (g) a spore sac fascus) .containing eight two-celled winter spores: (h) winter spore (ascospore) 

 very highly magnified. (Longyear.) 



