TREES AND SHRUBS 



Where the bark is destroyed all round the branch, the portion above the 

 wound is at once killed. On older parts of the tree the fungus will often 

 gain an entrance through a crack in the fork of a branch, and after becoming 

 well established will travel up the branch and cause its destruction by burst- 

 ing through the bark at different points along its course. If the cracks con- 

 taining the fungus be examined in spring there will be seen minute red dots 

 growing in clusters on a white mycelium. These smooth spherical dots are 

 the perithecia or conceptacles, and contain a pulpy nucleus consisting of a 

 great number of long cylindrical tubes, or asci, each enclosing a row of eight 

 spores. On germinating these spores give rise to the summer stage of the 

 fungus, which may be seen as minute white specks nestling in the crevices 

 of the rugged bark surrounding the wounds. 



The white stage of the fungus can be killed by applying with a brush 

 a solution of sulphate of iron — 1 lb. to a gallon of water. Young branches 

 that are attacked should be cut off. In older branches the diseased parts 

 should be cut away, and the cut surface carefully anointed with gas tar. 



The canker fungus is said also to attack Pear, Plum, Oak, Beech, Ash, 

 Hazel, Alder, Maple, and Lime. 



Apricot Brown Rot, Monilia fructigena, attacks the fruit of Apple and 

 Pear in England, and of Apricot, Peach, and Cherry in the United States 

 of America. The disease appears as a discoloured brownish spot, soon followed 

 by the growth of dull grey tufts arranged in irregular concentric rings. The 

 tufts are composed of dense masses of spores arranged in long branched chains. 

 Although most conspicuous on the fruit, the fungus usually attacks the leaves, 

 forming thin, velvety, olive-green patches, and from these the spores are carried 

 to the blossoms or young fruit. If allowed to follow its course undisturbed 

 for some years, the fungus may attack and kill the young shoots. The in- 

 fected fruit becomes dry and mummified, like a large mouldy Plum, and in 

 the spring produces a copious supply of spores to carry on the disease. The 

 second or ascigerous stage of the disease has been found in the United States 

 growing abundantly on old half-buried peaches. 



All dead twigs and shrivelled fruit should be collected and burned during 



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