DISEASES. 187 



that should be applied to our own neglect, or want of 

 forethought and care. 



• After having reviewed the whole subject, it may be safe 

 for us to conclude that what is called disease in our culti- 

 vated vegetables of whatever kind, is a departure from 

 full health and productiveness of sound fruits. And 

 further that this may arise from a lack of the necessary 

 ingredients in the soil, from a want of proper conditions 

 as to its quality and constitution, particularly with regard 

 to the important elemejits of moisture, heat, and light ; 

 and especially, that this condition of unhealthiness and 

 unproductiveness, when not an inherent failing of the va- 

 riety, may in many instances be attributable to want of 

 proper care on our part, and to our allowing the trees to 

 injure themselves by overbearing, while we neglect to keep 

 up the proper supply of nourishment. 



In making selections of trees for planting, it is import- 

 ant that all weak or unhealthy varieties should be avoided. 

 Secure healthy and vigorous stocks, that appear to be pos- 

 sessed of a sound constitution, even though the friiit 

 should not be quite so fine and beautiful as that produced 

 by some of the sickly and less vigorous varieties. There 

 is more difference apparent, in this respect, among pears 

 than among apples ; but of the latter there are varieties 

 that should be avoided on account of their deficient vigor. 

 There are others that might be considered as coming un- 

 der the ban, because the trees are not long-lived ; and yet 

 some of these appear to be perfectly healthy in every 

 othef respect, and seem literally to wear themselves out 

 by excessive bearing, producing .annual crops of large and 



