Retrospective Criticism. 357 



trees against its walls, all in a healthy state ; they grew rapidly and luxu- 

 riantly, but, after some time, I found that, though uninjured by any acci- 

 dent, their shoots gummed and cankered, and that a great proportion of the 

 growth they made in summer died down the season following, though the 

 soil was good kitchen-garden ground, full two spades deep ; dry, on a dry 

 substratum, and in a situation sufficiently airy ; but the subsoil was a ferru- 

 ginous clay, and the upper stratum partook of its nature: here this general 

 cause brought a general diseased state of the trees, which I found incurable ; 

 but where I removed the upper soil, and replaced it by fresh sweet earth 

 from another quarter, after rendering the subsoil impervious to the roots of 

 trees by a layer of stones and rubble, the new-planted trees which I substi- 

 tuted grew perfectly clean and healthy from thenceforward. It is also 

 notorious, that buds or grafts- taken from trees diseased as these were pre- 

 serve a taint which sooner or later breaks out, being, as in the analogous 

 case of scrofula in the human frame, constitutional. Old garden ground, 

 saturated with carbonaceous matter, rarely grows healthy fruit trees, parti- 

 cularly peach trees. To general causes must these general effects be attri- 

 buted; and to those enumerated, along with the operation of raw cold 

 seasons* are these diseases generally owing, and I have ever found them 

 incurable when produced by such, though the health of the tree may be 

 improved by judicious treatment. On the contrary, I have never known 

 local injuries by wounds or bruises, if partial, affect the general health of 

 the tree ; or prove fatal, except to the limbs on which they were inflicted, 

 and that by extreme neglect ; they operate only on the contiguous parts, not 

 by the circulation of deteriorated sap through the general system. 



Excision of the adjoining injured parts, and exclusion of air and moisture 

 by some adhesive composition, I have found sufficient for the purpose. Sir 

 Humphry Davy's recipe of neutralising the alkaline juices of the plant by 

 acid potations, however" chemically ingenious, would, I fear, prove worse 

 than the disease, and kill before it could cure; The application of manures 

 to the roots of gummy or cankered trees, is, in my opinion, injurious, as 

 they are generally disposed to grow too luxuriantly without it ; their habit 

 is plethoric. I should prefer a contrary course;- checking their growth by 

 transplantation into wholesome maiden soil. There is a local disease, the- 

 mildew, which unless early arrested, will affect the general health of the 

 peach tree, but only by the spreading of the infection externally ; and as 

 some of your correspondents have made enquiries respecting its cure, it 

 may not be unacceptable to them to learn that I have always found the use 

 of sulphur an effectual remedy, if early and perseveringly applied, mixed up 

 with water, or soap suds which are more adhesive ; it should be dashed 

 heavily over the tree by a syringe, particularly on the extremities of the 

 young shoots, which should be kept closely laid in ; and, being of opinion 

 that the mildew is a parasitic plant which disperses its seeds widely, I 

 would recommend, by way of prevention, that such peach trees as are in 

 the neighbourhood should also be syringed, though those only which have 

 leaves unfurnished with glands are liable to be infected by the mildew. 

 Yours, &c. — John Robertson. Kilkenny, Feb.' 20. 1830. 



The Epsom Nursery. — I have been a reader and admirer of your Gar- 

 dener's Magazine from its commencement, and have felt a high degree of 

 satisfaction at its success and wide circulation. Admitting that it is your 

 privilege, as Conductor, to introduce what matter you think proper into its 

 pages, it remains optional with gardeners and the public whether they will 

 purchase your books (Numbers) or not. But there is one circumstance in 

 which periodicals differ from other books. If the subject of another book 

 is not to my taste I need not buy it; but if I am a regular subscriber for 

 your Magazine (No. XXIV. for instance), I take it on the belief that nothing 

 will be foisted into it to supersede interesting and valuable matter, generally 



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