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because the latter is always more or less absorbent of 

 moisture, and is liable to injury by rain and frost, 

 causing alternations of moisture and dryness to the 

 wounds, that promote decay rather than their healing > 

 by the formation of new wood and bark. The re- 

 sinous plaster seldom or never requires renewal. Mr. 

 Forsyth, the arch advocate of earthy and alkaline 

 plasters, finding that they promoted decay, if applied 

 to the wounds of autumn-pruned trees, recommends 

 this important act of cultivation to be postponed to 

 the spring. If a resinous plaster be employed, it ex- 

 cludes the wet, and obviates the objection to autumnal 

 pruning. Mr. Forsyth's treatment of the trunks and 

 branches of trees, namely, scraping from them all the 

 scaly, dry exuviae of the bark, is to be adopted in 

 every instance. He recommends them to be brushed 

 over with a thin liquid compound of fresh cow-dung, 

 soap-suds, and urine ; but we very much prefer a brine 

 of common salt. Each acts as a gentle stimulus, 

 which is their chief cause of benefit ; and the latter 

 is more efficacious in destroying insects, and does not, 

 like the other, obstruct the perspiratory vessels of the 

 tree. The brine is advantageously rubbed in with a 

 scrubbing, or large painter's, brush. Some persons 

 recommend a liquid wash, containing, as prominent 

 ingredients, quick-lime and wood ashes, which, as the 

 disease arises from an over-alkalescent state of the 

 sap, cannot but prove injurious, and aggravate the 

 disease. 



