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and no thoroughly effective remedy for it has been found. One of the 

 causes appears to be over-luxuriant growth and an excess of sap. Severe 

 pruning undoubtedly is a cause of the disease, and more especially when 

 large branches are removed. The disease may also be induced by the 

 action of boring or bark-puncturing insects. In fact, wounds of any 

 kind in wood more than one year old encourage the direct exudation 

 of sap and the formation of masses of gum. The only means by which" 

 gumming can be reduced to a minimum is to practise systematic 

 summer pruning, and avoid winter cutting as far as is practicable. The 

 wounds made in the young shoots are small and heal quickly during the 

 period when growth is active, consequently there is little or no loss of 

 sap. When large wounds have necessarily to be made they should, 

 without delay, be painted over with some composition that will prevent 

 the exudation of the sap, and afford protection from sun, wind and rain. 

 A good composition is formed by a mixture of two parts resin and one 

 of shellac, melted together, with a little tallow added. Though there is 

 no absolute cure for the disease, it will be advisable to scrape off the 

 gum masses upon affected trees, and paint over the parts that were 

 touched with the composition. 



Leaf Galls. These may be caused either by the attacks of insects or 

 fungi, and though in most cases they are not sufficiently numerous to 

 materially affect the vigour of the plants, yet sometimes they cause 

 serious injury. Their formation necessarily causes a derangement of the 

 circulatory system, more or less, and though only certain parts of the 

 foliage may be affected, yet the plant loses in vigour. Then, again, 

 these galls afford breeding grounds for the development of particular 

 insects and fungi. Whenever galls make their appearance, if few in 

 number, and they can be easily reached, it will be advisable to remove 

 the affected leaves by hand and burn them, so as to destroy the germs 

 of whatever may have caused the trouble. If this plan is not practic- 

 able, as will be the case with large trees, or when the galls are very 

 numerous, the affected plants should be frequently sprayed with some 

 solution for insects or fungi, as the case may demand. Bordeaux Mix- 

 ture and Resin compound are effective remedies, as are also fresh slaked 

 lime and sulphur dusted over the foliage. 



Root Galls. Trees are often troubled with excrescences that form 

 upon the roots and small fibres, which consequently are unable to perform 

 their proper functions, and the plants perish sooner or later. On their 

 first appearance they are in the form of small swellings or " galls " of 

 various shapes, and they sometimes increase in size up to the diameter 

 of half-an-inch or more. Some plants will succumb in a few weeks after 

 they are attacked, but, on the other hand, strong, well-established trees 

 may be able to withstand the disease for several years. But the vitality 

 of the strongest trees will steadily decrease after they are attacked, and 

 they will gradually die off. The cause of this disease is due to Nematode 

 worms of various species which establish themselves in the soil. These 

 insects, commonly known as Thread Worms, or Flask Worms, are very 

 minute, and their mode of action is to bury themselves in the roots, and 

 whenever this is done " galls " are formed. As the insects increase 



