NOTES ON THE DISEASES OF FRUIT TREES IN THE WEST. 



many of those proposed, are entirely at war with the facts as they appeared here, though 

 they may apply well elsewhere. 



By the way, the erysipelas has appeared more fatally in the human subject in these 

 parts, within a few years, than was ever before known. Do the same atmospheric or oth- 

 er causes, conduce to both diseases in the animal and vegetable world? Let us observe 

 and inquire. At all events, if no remedy is found, it will be useless to attempt to culti- 

 vate pears in this western country. 



It should be noticed, however, that the only pear trees of twenty or twenty-five 

 years old, in this vicinity, have stood for many years in an unbroken sward of blue 

 grass, which is hard and compact. Some of these trees were somewhat blighted at the 

 top, but far less than younger trees differently situated. One seedling tree in the same 

 lot,. standing in a cultivated garden, about fifteen years old, showed not a single blighted 

 leaf, while all others near it were blackened more or less. 



It is certainly true here, that trees grafted upon entire seedling roofs, and trees stand- 

 ing in a hard, tough, blue grass sward, have escaped all forms of blight as yet, far better 

 than others, [which is partly owing to their making very moderate growth — instead of 

 running into over-luxuriance, and partly to the grass protecting the roots from excessive 

 changes — like mulching. Ed.] 



The blight to which I alluded in a former paper, and which has heretofore prevailed 

 here, starts from the south-west of the trunk and large branches, and spreads both up- 

 wards and downwards, while the leaves are still unafiected; and seems precisely like that 

 form of blight which is described by your correspondent as killing his apple trees in Mo- 

 bile, in the December No. of the Horticulturist. I cannot have been mistaken in calling 

 this form of blight a severe scald — the facts here abundantly prove it. Beside, how do 

 your advocates of the frozen-sap theory, account for the above case. Does frost kill ap- 

 ple trees in Mohili 1 I apprehend they would be killed still worse in the same way, far- 

 ther south, if their trunks were exposed to the scalding sun, continually drying the liquid 

 sap into solid gum. But while the blight of former years thus began, and appeared to 

 spread like a general mortification of the animal tissues, the blight of this year appeared 

 to begin on or near the extreme twigs and small branches, at once affecting the leaves, 

 while still the trunk and large branches Avere entirely sound — and spreading mostly down- 

 wards, first on the outer bark, like erysipelas, and not by a general simultaneous black- 

 ening and gangrene of the interior tissues, as in the other case. 



Again, it frequently began on the most shady side of the tree, even where the sun never 

 shown upon the branch; and while extreme heat is the only known cause to which I can 

 ascribe the disease in this latter case — still it operated by producing a general paralysis of 

 the functions of the cuticle, if at all, and not by a sudden scald of a particular part of the 

 trunk, as in the former case. I have been thus particular and tedious, because it is, in my 

 present view, as absurd to suppose all blights in trees are alike, as it is to suppose all 

 fevers and inflammations in men and animals alike. It is true, a blight is a blight, and so 

 a fever is a fever, whether produced by cold or heat, or miasma or surfeit, or starvation; 

 but phjrsicians find it quite convenient, after all, to distinguish between fevers and their 

 causes, before they prescribe remedies — and that both frost, and heat, and miasma, and 

 animalculaS, and surfeit, and starvation may, in different localities produce different modes 

 and forms of this baleful pear tree fever, has at least, been rendered sufficiently probable 

 to awaken suspicion and inquiry. Let us try, therefore, to obtain accurate descfip 

 of its forms and modes in different places and seasons, as the only sure first 



truly philosophical investigation. It is certainly, however, about as dangerous here 



