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scion may also bring about the trouble. Improperly fed trees, or 

 trees supplied with indigestible (unassimilable) food, are less apt 

 to withstand the attack, and succumb. 



The trouble shows in a variety of ways. The young spring 

 shoots suddenly collapse and wither. In that case, cut hard back 

 before the poisonous sap can travel back to the healthy parts. In 

 other instances, the foliage and twigs seem all right, but the fruits, 

 when the size of a walnut, stop growing, turn brown, and show a 

 gummy exudation on dark-coloured patches. A microscopic 

 examination discloses the presence of numerous fungi, often of the 

 Macrosporium tribe. A liberal dressing of 51bs. to lOlbs. of super- 

 phosphate of lime in the winter often saves trees predisposed to 

 gumming. 



A somewhat similar disease, supposed, however, to be of 

 bacterial origin, at times attacks young apricot trees, when two to 

 four years old. It is recognised by the leaves or part of the tree 

 turning yellow and falling off. The limbs from which the leaves 

 fall, when cut through, shows a black heart. 



Prune these limbs back as far as they show the black heart, 

 and also shorten the limbs that are not diseased. Disinfect the 

 knife after it has come into contact with the diseased sap. 



LEAF RUST (Uromyces Amygdale, Cook, and Puccinia pruni 

 spinosce, Pers.). Very prevalent in damp localities (late in the 

 summer) on peach trees, and also the almond, nectarine, apricot, 

 and plum. 



The leaves are picked with yellow spots on the upper surface 

 of the leaf ; these yellow spots are often surrounded with a purplish 

 ring, and they have on the other side of the leaf brown spots of 

 fungoid growth. The leaf tissue attacked by these spots become 

 eaten away into holes, and the leaf falls, beginning from the butt 

 end of the branches, and the wood does not ripen as it should do, 

 thereby enfeebling the tree. 



Remedies. Collect and burn all affected leaves to destroy the 

 summer spores, which remain inert during the winter only to infect 

 the next year's growth. Spray early in the season with Bordeaux 

 Mixture, half strength, or other fungicides. 



LEAF SCALD (Entomosporium Maculatum, Lev.) attacks the 

 leaves of apples, pears, quinces, peaches, cherries, etc. (says Massee). 

 These fall early in the season, and in bad attacks leave the trees 

 defoliated. A second growth of leaves follows, and at times these 

 suffer in the same way. As a consequence, the trees are much 

 weakened. 



Small red spots appear on the upper surface of leaves when 

 still young; these increase in size and become brown, having one or 

 more minute black spots slightly above the general surface. If the 

 spots are numerous, the leaves become brown, shrivel, and fall off. 

 If the leaf is older, with rigid tissues, it retains its shape, but falls 

 to the ground. 



