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by severe and careless pruning and the exposure of rough 

 wounds to atmospheric influences. Root canker is often caused by the 

 non-removal of broken or bruised roots when the trees are planted. 

 The disease may also, in some cases, be the result of insects that feed 

 upon the bark and woody tissues. Fungi will sometimes be the cause, 

 and it may be brought about by lichens and mosses growing upon the 

 trees. As a matter of course a disease originating from such various 

 causes, and affecting trees in different ways, cannot be treated by any 

 general remedy. When branches are affected they should be amputated 

 when practicable. Shoots that have their points touched should be cut 

 back. Cankered roots should be cut away when practicable, and every 

 effort ought to be made to prevent the disease from spreading. But 

 when the trunks or roots are badly cankered, but little can be done 

 towards saving the trees. The disease should be treated as soon as it 

 can be detected, and predisposing causes must be avoided, as far as may 

 be practicable. 



Fire Blight. This is a disease whose origin is somewhat obscure, 

 and there are various opinions as to the cause. Some authorities 

 consider that the disease germ is a species of bacteria, but others are 

 of opinion that the cause is to be attributed to influences that affect the 

 circulation of the sap. The writer's views are in accordance with the 

 latter opinion, and a long experience has convinced him that it is a 

 feasible one. In the summer, sometimes, when the sun is very powerful, 

 and the bark of the trees exposed, the sap becomes unduly heated. 

 When this occurs the sap does not circulate under normal conditions, 

 and consequently becomes more or less poisoned. This poisoned sap 

 will show in patches, which spread rapidly, and the wood and foliage 

 dry up. Trees that are affected have a withered, blighted appearance, 

 as if scorched by fire, and hence the name, " Fire Blight." Sometimes 

 the disease attacks a tree in various places, and cause its death. In 

 other cases it confines its attacks to a few branches, which are destroyed, 

 though the tree in other parts is not affected. The disease is more 

 especially prevalent among pear trees, though its ravages are not 

 confined to them alone, as is generally supposed. As regards remedies 

 there are none, so far as is known. Possibly its ill-effects may be 

 reduced to a minimum by carefully training and pruning, so that the 

 foliage will afford effective shade to the stems and branches. In the 

 case of young trees, whose heads are not large enough to afford perfect 

 shelter, the stems should be protected by artificial means during the 

 hottest portion of the year. When the disease appears on the branches 

 they should be cut back some distance beyond the affected parts, so as 

 to get rid of as much of the poisoned wood as possible. 



Gumming. This is one of the most troublesome diseases with which 

 fruit-growers have to contend, and, unfortunately, it is very common 

 in this part of the world, as also in Europe and America. The disease is 

 confined to stone fruits, and it more particularly affects the Apricot, 

 Peach and Cherry. It is caused by the glutinous sap exuding from 

 wounds or cracks in the bark and forming masses of gum, hence 

 the name. The causes of this disease are not known with certainty, 



