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advanced by A. J. Downing in the first edition of his “Fruits 
and Fruit Trees of America’’ which appeared in 1845. The 
name “Frozen-sap blight” was there applied to the disease. 
The theory being that the disease was due to freezing 
and thawing of the sap which thus lost its vitality, became 
dark and discolored, and poisonous to the plant. He says 
a damp warm autumn, followed by a sudden and early win- 
ter, always precedes a summer when blight is very prevalent. 
In enumerating the symptoms of the disease, Mr. Down- 
ing gives just those characteristic features with which every 
one who has come in contact with the disease is familiar. 
The thick gummy exudation from diseased tissue, the dark, 
discolored areas of bark that follow attacks upon the trunk 
and branches, and the sudden blackening of growing extrem- 
ities in early summer. 
No fault can be found with all that Mr. Downing says 
of symptoms, and of circumstances attending the disease; 
but he was wrong in many of the conclusions drawn, and in 
the wide application he makes of conditions that prevailed 
Only locally. Of remedies Mr. Downing says: “The most 
successful remedies for this disastrous blight, it is very evident, 
are chiefly preventive ones” “As a remedy for blight 
actually existing in a tree, we know of no other but that of 
freely cutting out the diseased branches, at the earliest 
moment after it appears.” 
In July, 1846, Mr. Downing began the publication of the 
“Horticulturist,” a monthly journal of “Rural Art and Rural 
Taste,” and in the second, or August number of that journal 
he writes at length of the blight, repeating the theory as 
advanced in his work of the year previous. 
OBJECTIONS TO THE FROZEN-SAP THEORY. 
In the December number for the same year, place is 
given for an article by a correspondent from Terre Haute, 
Indiana, who signs himself S. B. G. This writer presents a 
number of observations which appear as valid objections to 
the frozen-sap theory, some of which I desire to quote. 
“If this theory be true, why have its effects manifested them- 
selves so recently? Our climate has undergone no change. 
The vicissitudes of weather have never been less than now. 
I have resided upon the Wabash more than twenty-three 
years and have known no difference in this respect. I have 
known almost whole winters that the plow might have run, 
while others have been cold. Late spring frosts, and late, 
warm, humid fall weather, have always marked our fitful 
