320 THE PLUM. 



stance whatever, where abundant crops have not been ob- 

 tained by combining the two remedies of swine and jarring 

 down the insects. 



The curculio appears to prefer the nectarine to all other 

 fruit for the lodgment of its eggs, and next to this the plum 

 and apricot. A large portion of the cherry crop is frequent- 

 ly more or less injured, and sometimes wholly destroyed ; 

 and for this reason it may usually be expedient to give it 

 the benefit of the protection of swine in the same enclosure 

 with other smooth stone fruit. The peach is sometimes at- 

 tacked, but only the very early nutmeg varieties wholly de- 

 stroyed. Some varieties of the apple are much stung, as 

 indicated by the crescent-shaped incisions : but the larvre 

 rarely reach so far as the core, and usually perish within the 

 flesh of the fruit. 



Among the various remedies which have been tried and 

 proved partial or entire failures, may be mentioned the ap- 

 plication of salt to the ground, beneath the tree, and its di- 

 rect application to the fruit ; syringing tobacco water over 

 the fruit and leaves; hanging bottles of sweetened water 

 in the branches to catch the insects, and placing white- 

 washed boxes with water in the bottom during the night, 

 with a lamp within each, to decoy them ;* and inverting 

 the soil with a spade late in autumn, to expose them to the 

 frosts of winter. 



The black excrescences on the shoots and limbs, fig. 246, 

 known as the black knot, black gum, and warts, 

 are variously supposed to be the \vork of an 

 insect, o-r the result of diseased sap or cells, or 

 regarded as a sort of vegetable ulcer. They 

 have been by some attributed to the curculio, an 

 opinion originating from the occasional detec- 

 tion of this insect within the pulpy excrescen- 

 ces, but entirely disproved by the facts that the 

 curculio has existed in vast numbers in neigh- 

 borhoods where the excrescences are unknown ; 

 and on the other hand, that the excrescences 

 Fig. '246. have lUined trees in places not infested 

 with the curculio; besides which, the most rigid search of 

 newly forming knots has failed to detect the-eggs or larvae 



* Which, however, prove very efficient means of destroying- many other insects 

 injurious to fruits and fruit trees. 



