?54 THE FRUIT GROWER'S GUIDE. 



Mr. Edmund Tonks, in a paper read at the Apple and Pear Congress of the Koyal 

 Horticultural Society, held at Chiswick, in 1888, recommends the following formula 

 for apple trees affected with canker: " Superphosphate of lime, 12 parts or pounds; 

 nitrate of potash (saltpetre), 10; chloride of sodium (common salt), 4; sulphate of 

 magnesia (Epsom salts), 2 ; sulphate of iron (green vitriol), 1 ; and sulphate of lime 

 (gypsum), 8. This may be used at the rate of a J pound to the square yard over the 

 whole extent of soil within reach of the roots. It need not be dug in. One effect of 

 the manure may be relied on : if it does not cure canker, it will, at any rate, most cer- 

 tainly benefit the trees." 



Trees not too old and canker-eaten are amenable to improvement by re-grafting. 

 A tree that never bears good fruit nor makes little beyond cankered growth may be 

 transformed into a healthy specimen, and bear fine fruit, by putting a new head on old 

 shoulders in the form of a number of grafts of a strong-growing hardy sort, always 

 provided there is nutriment in the soil for the roots to appropriate. Strong-growing 

 apples and other fruit trees established on weakly trees increase their root action, and, 

 finding the requisite support for the growths, new layers of wood form on the old stems, 

 covering over wounds, and a new lease of life is thus given to the trees. Stunted trees 

 necessarily have weak roots, not extending far from the stems ; therefore, by establishing 

 a strong-growing variety on a weak one, strength is imparted to the roots, and these push 

 beyond the hitherto small impoverished occupied radius into fresh, practically virgin 

 soil. Strong growing and rooting sorts will live where the weaker fail, but where the 

 food is scant it will sooner be devoured ; hence re-grafted trees often grow very well 

 for a few years and then collapse. They succumb because the soil is deprived of its 

 available resources of nutrition, and it is the duty of cultivators to keep it replenished 

 with food that is needed for the health of trees and supporting their crops of fruit. 



When Nectria has affected a branch half or more round, cure by any other means 

 than excision or amputation of the affected part is doubtful. With the cankered part 

 cut clean out, the wound heals over if the wood is healthy. Before cutting out the 

 canker, wash it well the day before with a 6 per cent, solution of sulphate of iron or | per 

 cent, sulphate of copper (blue vitriol). Pare the wound quite smooth, taking care not to 

 injure the edges of healthy bark. Dress the wound with the alcohol and shellac styptic. 

 Large wounds should be covered with grafting pigment. The operation should be per- 

 formed in spring or early summer, to allow of the wound healing over as quickly as possible. 



Gum. Though similar to canker, gum does not affect apple and pear trees ; but 



