238 Observations upon the effects of Frost, 



hope for certain success in the important object of introducing 

 exotic species hardy enough to bear our climate ; consequently to 

 multiply and systematize such observations is one of the most 

 useful employments in which the horticulturist can engage. It is 

 far more likely to lead to results of importance than attempts to 

 acclimatize plants ; an object which has already occupied so much 

 time to so little purpose, that I doubt whether any one case of ac- 

 tual acclimatization can be adduced ; that is to say, any one case 

 of a species naturally tender having been made hardy, or even 

 hardier than it was originally. Not to mention other cases in point, 

 Cerasus Laurocerasus is as tender as it was in Parkinson's 

 time, and yet it has been raised from seeds through many genera- 

 tions ; the potatoe retains its original impatience of frost, and so 

 does the kidney bean, which last might at least have been ex- 

 pected to become hardier, if reiterated raising from seed in cold 

 climates could bring about that result. The many beautiful and 

 valuable half-hardy hybrids, lately provided for our gardens, are no 

 exception to this statement, for they are not instances of a tender 

 species being hardened, but of new and hardy creations obtained 

 by the art of man from parents, of which one is hardy and the 

 other delicate. Acclimatization, in the strict sense of the word, 

 seems to be a chimaera. 



What gives such evidence, as is now about to be adduced, its 

 great value, is the well known fact, that no botanist can ever 

 tell with precision whether a plant will support a climate to which 

 it is unaccustomed. No one has as yet succeeded in pointing out 

 any decided connection between the structure of plants and their 

 powers of enduring cold, and consequently we cannot judge a priori 

 what amount of cold a given plant will bear. If this could be 

 effected, one of the most important of all steps would have been 

 taken in the progress of horticulture, and we should be spared the 

 loss and disappointment which now attend all extensive attempts at 

 naturalizing exotic species. It is undoubtedly true, that particular 



