Blight on Fruit Trees. 279 



affects the tender leaves ; for their transpirable matter is 

 thereby thickened, and rendered glutinous, closely adhering 

 to the surface of the leaves, and becoming a proper nutriment 

 to small insects, which are always found preying upon the 

 leaves and tender branches of fruit trees whenever this blight 

 appears. But it is not, as some suppose, those insects which 

 are the cause of blights, though it must be allowed that, when- 

 ever they meet with such suitable food as a blighted tree fur- 

 nishes, they multiply exceedingly, and are instrumental in 

 aggravating the disease. 



The remedy for this description of blight which I have yet 

 found to succeed best, is to well wash over the trees daily with 

 the softest water that can be procured, rain-water, if possi- 

 ble, mixed with a little dung water ; a small quantity of sul- 

 phur being mixed in the water, previous to using it, and the 

 operation performed as early as possible in mild mornings. 

 If the young plants are much infected, wash them carefully with 

 a sponge, so as to free them from glutinous matter. Another 

 cause of those blights, which prove most destructive to fruit in 

 the spring where no precautions jare used, is the sharp frosts 

 which happen when the blossom and young fruit is in danger ; 

 for every gardener knows that at this season we often find a 

 hot sun after very frosty nights. The best remedy I find for 

 this evil, is to wash the frost all off the trees before the sun 

 gets on them ; by so doing, I have found no bad effects from 

 sharp frosts. 



Other blights prevail from inward weakness and distempers 

 in trees, occasioned from a want of sufficient nourishment to 

 maintain them in perfect vigour, or from some ill qualities in 

 the soil where they grow ; or perhaps from some bad quality 

 in the stocks, on which the trees are grafted ; or perhaps from 

 some constitutional distemper in the buds or scions of the 

 parent tree ; or from many other evils which trees are subject 

 to. If the soil be a hot burning gravel or sand, you will find 

 this will be constantly the case, after their roots have got be- 

 yond the earth of the borders. In such cases it is better to 

 change the sort of trees for such as the soil suits better. 



There is another kind of blight that sometimes proves very 

 destructive to both fruit and forest trees, in orchards and open 

 plantations, and against which I should be glad to find a 

 remedy. This is what is called the fire-blast ; an evil which 

 ill a few hours destroys the fruit and leaves, and sometimes 

 the whole tree. The fire-blast is supposed to be effected 

 by volumes of transparent flying vapours, which, among the 

 many forms they assume, may sometimes approach so near 



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