CHAPTKU III. 

 GENERAL REMARKS ON PEARS. 



The excellence of lliis fruit is universally ncknowledged, and were it. not for the diffirnlty 

 of cultivating it, few individuals would deprive tlieniselves of tlie luxury it furnishes. 

 But in consequence of the diseases to which the tree is subject, and the ill success which 

 has attended many in the attempts to cultivate it, it is, to say the least, far less in use 

 than it otherwise would be. The greatest evil which the pear tree has to encounter, is the 

 fire-blight. What this disease is, or what is its essential nature, has never been told. If 

 vegetables can be supposed capable of inheriting the diseases of the higher orders of beings, 

 if it could be proved that high vital action, as in the case of animals, could end in mortifi- 

 cation or gangrene, then we might be justified in pronouncing the fire-blight a gangrene, 

 a tree mortification. Whether such a view can be maintained or not, may be regarded as 

 questionable; still, the phenomena of the disease, from beginning to end, resemble what 

 takes place in the mortification of an arm or leg. We have not, however, the means for 

 determining the nature or character of the circulating fluids, or the condition they may be 

 in at the time of the onset of the disease. We have, however, some facts which throw 

 a feeble light upon the question. Atmospherical agents seem to play a part in its develop- 

 ment. For instance : that peculiar state of the weather, which is called sultry, when it 

 is succeeded by a scorching sun, is quite influential in the production of blight; or the re- 

 lations of the supposed cause stand to the blight somewhat as antecedents and consequents. 

 I made some observations on this disease in 1847, and as I have not seen cause to change my 

 opinion, I propose to repeat them in part in this place.* It is proper, in the first place, that 

 the term blight should be restricted to one disease. For instance : the Scolylus pyri, of Peck, 

 girdles a limb and it dies, and when dead looks as if if had perished from the real blight ; 

 but this is no blight at all, and the remedy which is applied with success in one case, is 

 entirely ineflicient in the other. The effect of remedies is one of the best tests in deciding 



* American Quarterly Journal of Agriculture and Science, July Ko. for 1847, p. 5. Aug. No. for Sept. p. 179. 

 [AOBICULTURAL RepOBT VoL. III.J 14 



