A REVIEW OF OPINIONS ON PEAR TREE BLIGHT. 



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A REVIEW OP OPINIONS ON PEAR TREE BLIGHT. 



BY L. C. EATON, OF PROVIDENCE, R. I. 



What is the malady by which fruit trees 

 are affected, called the Jire blight? Before 

 we examine for a cause to which to ascribe 

 its origin, it is necessary to determine what 

 are its peculiar symptoms ; and until we do 

 so, investigation will lead to no satisfactory 

 results. The term blight, of itself, express- 

 es no particular disease, and defines merely 

 the blasting or withering of plants Avhile in 

 a state of growth. " What is called 

 blight," says Forsyth, " is frequently no 

 more than a weakness or distemper in 

 trees. This is the case when trees against 

 the same wall, and enjoying the same ad- 

 vantages in every respect, differ greatly in 

 their health and vigor, the weak appearing 

 to be continually blighted, whilst others re- 

 main in a flourishing condition. This very 

 great difference in such circumstances can 

 be attributed to the different constitutions of 

 the trees, proceeding from a want of proper 

 nourishment, or some bad qualities in the 

 soil, some distemper in stocks, buds or sci- 

 ons, or mismanagement in the pruning, 

 &;c., all of which are productive of distem- 

 per in trees, of which they are with diffi- 

 culty cured; "and he states that there is 

 another sort of blight against which we 

 know of no effectual remed}-, called the fire 

 blast." Trees sometimes perish by great 

 heat, when accompanied by a severe 

 drouth, and by cold even in the spring, 

 when so rigorous as to destroy the foliage. 

 A partial destruction or mutilation of the 

 roots, deep planting, an uncongenial subsoil, 

 cankers produced by bruises, neglect of cul- 

 tivation, moss and vermin, do not unfre- 

 quently occasion disease having some of 

 the marks characteristic of the fire blight ; 



and trees which have perished from either 

 of these causes may have been supposed to 

 have been affected by this malady. Differ- 

 ent diseases have been confounded togeth- 

 er, not simply by the inattentive, but by 

 men of experience and investigation. 

 Judge Buel, in a communication to the New- 

 Engla7id Farmer, in 1828, ascribes the fire 

 blight to an insect, and refutes all theories 

 attributing it to any other origin. He pro- 

 bably had only examined trees injured b}'^ 

 the insect Scolytus pyri, described by Pro- 

 fessor Peck. An article from a correspon- 

 dent in New Jersey, referring to and refut- 

 ing the opinion expressed by Judge Buel, 

 was published the next j^ear in the same 

 paper. " It has been my object," he says, 

 " for many years, to ascertain the cause of 

 this destructive disease, but vigilant as I 

 have been and still am, I have never yet 

 detected any insect in the act of puncturing 

 a tree, so as to cause fire blight." The ed- 

 itor of the Gc/iesce Farvier in 1833, discuss- 

 es this question, and after reviewing the 

 opinions of different observers, gives his 

 views, Avhich coincide with those of Judge 

 Buel. It does not seem to have been con- 

 jectured by either of these writers, that 

 there were or might be two distinct diseases 

 originating from different causes, and pro- 

 ducing the same or similar results. Though 

 they are very dissimilar, yet the one, we 

 believe, is often mistaken for the other. 

 Downing, in his treatise upon Fruit Trees, 

 has described what are the peculiar symp- 

 toms of each. 



The origin of the fire blight has been 

 much discussed, and various theories have 

 from time to time been advanced, meeting 



