CALCIUM OXIDE (QUICKLIME). 145 



cellent method of diminishing the number of these parasites. The 

 previous cleaning of the trunks removes all moss, lichens, and bark 

 which formed so many refuges in which the insects and their larvae 

 pass the winter and lay their eggs. It plays as great a role as the 

 liming itself. All the hiding-places preferred by these parasites are 

 destroyed, and not knowing where to deposit their progeny they are 

 obliged to seek refuge elsewhere. Against cochineals lime exerts a 

 special mechanical action ; their shell, covered by a thick layer of lime, 

 is, owing to the contraction of the lime, detached from the branch on 

 which it was fixed, thus causing its death. 



Liming of Trees. — This practice advised by Blanchere is a very 

 good one for it frees the trees well from parasites. The strength of 

 the milk of lime may be increased to a thick paste without injuring 

 the tree. To secure good disinfection it is better not to use milk of 

 lime alone but mixed with tar and naphthalene as advised by Balbiani, 

 To complete the work of liming it is well to collect and burn all the 

 broken particles of bark and to bury with quicklime all the fallen fruit. 

 As it slakes the lime destroys the parasites by the heat given off. By 

 this means the number of anthonomes, cheimatobias, and even 

 schizoneura lanigera (woolly aphis) are greatly diminished. The re- 

 sults will be more complete the more regularly the liming is repeated, 



Scolytides. — The Bostrichi and the Hylesini, injurious to conifers, 

 the scolytides, injurious to deciduous forest trees, cannot be destroyed 

 by liming the trunk, but regular whitewashing with lime may remove 

 them. Again whitewashing with thick and pliant lime m autumn 

 after scraping the tree stops the exit orifice of the scolytides and renders 

 the baik less accessible to the female in winter. Eobert advises summer 

 liming. If during summer a tree is badly infested by these insects 

 there must be no hesitation in making longitudinal cuts or a surface 

 barking, taking care immediately afterwards to coat the wound or the 

 trunk with milk of lime. But when the tree is too far gone it is pre- 

 ferable to fell it and burn it, taking care to protect all the adjacent trees 

 by liming or with the coating described further on. This opera- 

 tion, extensively applied in Austria, consists in painting the trunks and 

 even the branches with a mortar made thus : Macerate 5^ lb. of tobacco 

 in 1-1 gallons of hot water kept at a rather high heat, add 11 lb. of ox 

 blood, and 11 lb. of lime and cow dung to a pasty consistency. The 

 trunks and branches are coated several times with this composition 

 until a hard weather-resisting coat is formed. 



Amongst the better-known scolytides there may be quoted 

 Eccoptogaster Pruni, Eatz. (scolytus of the plum). E. regulosus, Koch, 

 (rugose scolytus). E. Scolytus, Eatz. (elm scolytus). Hylesinus oliperda 

 (hylesinus of the olive-tree, cirai, taragaon). Tomicus Ficus, Er. (bostrich 

 of the fig). Tomicus Mori, Aub. (bostrich of the mulberry). Bostrichus 

 dispar (apple bark beetle), Hllw., and B. saxesmi, Eatz., both injurious 

 to fruit trees. All these scolytides may be removed by the above 

 treatment. 



Colaspidema atrum, 01. (negril). — Debray recommends liming of 

 lucerne the moment the young larvae commence their inevitable invasion, 

 but so as not to be forced to lime all the field of lucerne it is well to 



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