536 NATUEAL SOIL NOT ALWAYS THE BEST. 



■vpill kill them.' " But Mr. Smith observes : " In our experience, we 

 have never found any plant thrive by retaining it in its native soil, or 

 in soil too closely resembling it. If we could also imitate all the 

 various influences of climate that modify and control the growth of 

 plants in their native localities, it might then be proper for us to 

 cultivate the Lace-bark tree in marly soil, like limestone; but our 

 plants afford evidence that such soil is not required when they are 

 grown in an artificially heated atmosphere. We have used good yellow 

 loam, mixed with a little leaf-mould and sand. In this they have 

 attained the height of 8 feet, and continue in a perfectly healthy state." 



This opinion is greatly supported by such facts as the fol- 

 lowing, which show that great numbers of plants have no 

 particular predilection for soil, or at least, that if they have we 

 cannot show it to exist, and that there are facts in the relation 

 between plants and soil which remain without explanation. 

 Mr. Knight observed that varieties of the same species of fruit- 

 tree do not succeed equally in the same soil, or with the same 

 manure : the Peach in many soils acquires a high degree of 

 perfection, where its variety, the Nectarine, is of comparatively 

 little value; and the Nectarine frequently possesses its full 

 flavour in a sml which does not well suit the Peach. The 

 same remark is also applicable to the Pear and the Apple ; 

 and, as defects of opposite kinds occur in the varieties of every 

 species of fruit, those qualities in the soil which are beneficial 

 in some cases wiU be found injurious in others. In those 

 districts where the Apple and Pear are cultivated for cider and 

 perry, much of the success of the planter is found to depend 

 on his skiU or good fortune in adapting his fruits to the soil. 

 {Hort. Trans., i. 6.) Ehododendrons and Kalmias are usually 

 cultivated in peat earth mixed with sand, and yet they grow as 

 well in fresh hazelly loam, without any mixture whatever; 

 and, than these two kinds of soil, none can be apparently more 

 dissimilar. The fine American cottons are grown in a cal- 

 careous sand, those of India in a deep black saponaceous earth ; 

 the American cotton will not thrive in the latter, nor that of 

 India in the former, as has now been ascertained ; and yet the 

 species of Gossypium producing the two qualities have no 

 organic differences which can, so far as has yet been ascer- 

 tained, explain in the smallest degree the necessity, under 



