CAN 



120 



CAN 



and although the gardener's, like the '' they sustain, however young and vigor- 

 physician's skill, may retard the onward I ous they were when first planted. 

 pace of death, he will not be perma- How inductive of this disease is a wet 

 iiently delayed. In the last periods ofi retentive subsoil, if the roots penetrate 



life they show every sym[)tom that ac- 

 companies organization in its old age, 

 not only a cessation of growth, but a 

 decay of former development, a languid 

 circulation and diseased organs. 



The canker, as already observed, 

 attends especially the old age of some 

 fruit trees, and of these the apple is 

 most remarkably a sufferer. " I do not 

 mean," says Mr. Knight, " to assert 

 that there ever was a time when an 

 apple-tree did not canker on unfavoura- 

 ble soils, or that highly cultivated va- 

 rieties were not more subject to the 

 disease than others, where the soil did 

 Tiot suit them. But I assert from my 

 own experience and observation within 

 the last twenty years, that this disease 

 becomes progressively more fatal to 

 each variety, as the age of that variety 

 beyond a certain period increases ; that 

 if an old worn-out orchard be planted 

 with fruit trees, the varieties of the 

 apple, which I have found in the cata- 

 logues of the middle of the seventeenth 

 century, are unproductive of fruit, and 

 in a state of debility and decay." 



Among the individuals particularly 

 liable to be infected, are those which 

 have been marked by an excessively 

 vigorous growth in their early years. I 

 had one in my garden at Great Totham, 

 which for the first twelve years of its 

 existence was remarkable lor the un- 

 naturally large size and abundance of 

 its annual shoots. It then became 

 grievously affected by canker, which a^t 

 length destroyed it. 



Trees injudiciously pruned or grow- 

 ing upon an ungenial soil, are more 

 frequently attacked than those advanc- 

 ing under contrary circumstances. The 



it, appears from the statement of Mr. 

 VVatts, gardener to R. G. Russell, Esq., 

 of Chequers Court, in Buckinghamshire. 

 — A border beneath a south wall had a 

 soil three feet and a half in depth, ap- 

 parently of the most fertile staple, twice 

 re-made under the direction of the late 



j Mr. Lee, of the Vineyard, Hammer- 

 smith. In this the trees, peaches and 



^ nectarines, flourish for the next three 

 or four years after they are planted, but 



1 are then rapidly destroyed by the 



I canker and gum. The subsoil is a stiff 

 sour clay, nearly approaching to a brick 

 earth ; and the disease occurs as soon 

 as it is reached by the roots of the tree. 

 But this is certainly not a conclusion 

 warranted by the premises, because the 

 acridity of the sap, whatever may be its 

 source, would be likely to injure and 

 corrode, in the first instance, those parts 

 where the vessels are most weak and 

 tender; now these, past dispute, are in 

 the branches. Moreover, we generally 

 see the youngest branches the earliest 

 sufferers. 



Pruning has a powerful influence in 

 preventing the occurrence of the canker. 

 I remember a standard russet apple- 

 tree of not more than twenty years' 

 growth, with a redundancy of ill-ar- 

 ranged branches, that was excessively 

 attacked by this disease. I had two of 

 its three main branches, and the laterals 

 of that remaining, carefully thinned ; 

 all the infected parts being at the same 

 time removed. The result was a total 

 cure. The branches were annually re- 

 guhited, and for six years the disease 

 never re-appeared. At the end of that 

 time the tree had to be removed, as the 

 ground it stood upon was required for 



oldest trees are always the first attack- another purpose. John Williams, Esq., 

 ed of those similarly cultivated. The I of Pitmaston, from long experience 

 golden pippin, the oldest existing varie- concludes, that the golden pippin and 

 ty of the apple, is more frequently and ' other apples may be preserved from 

 more seriously attacked than any other. I this disease, by pruning away every 

 The soil has a very considerable influ- year that part of each shoot which is 

 ence in inducing the disease. If the , not perlectly ripened. By pursuing this 

 subsoil be a ferruginous gravel, or if it I method for six years, he brought a 

 is not well drained, and the soil be alu- i dwarf golden pippin tree to be as vigor- 

 niinous, and effective means are not | ous and as free from canker as any new 

 adopted to free it of superabundant variety. 



moisture, the canker, under any one of j All these facts unite in assuring us 

 these circumstances, is almost certain that the canker arises from the tree's 

 to make its appearance amongst the trees i weakness, from a deficiency in its vital 



