OF THE 



UNIVERSITY 



TEXTURE. 



the air penetrates it and water moves through 

 it, its water-holding capacity, and finally its 

 temperature.* 



By varying the texture of the soil its water 

 content is varied, its capacity for heat is modified, 

 and so on until every important factor, including 

 food, in the ordinary acceptance of the word, is 

 involved. To these variations the plant adapts 

 itself, and the result may be extensive leaf develop- 

 ment with few or no flowers or vice versa, a weak- 

 ened condition of the tissues (making the plant 

 subject to the attacks of enemies, especially fungi), 

 and so on through a list of other possibilities. To 

 illustrate more fully, we may say that in our 

 experience the Lady Hume Campbell violet seems 

 to thrive best on relatively light soil, that is, a 

 soil which contains a comparatively small amount 

 of clay. The Marie Louise, on the other hand, 

 does best with more clay, or in other words a 

 heavier soil. The violet soils of the Poughkeepsie 

 region contain from eight to fifteen per cent of 

 clay, and it is here that the highest success is 

 attained with this particular variety. In parts of 

 Maryland and Virginia where the Campbell violet 

 is grown extensively, the soils frequently contain 

 six to eight per cent of clay, so that it will be seen 

 that there is considerable difference as regards the 

 structure of the two classes of soils. It follows, 



*Galloway, B. T,, Yearbook of the Department of Agriculture for 

 1895, p. 250. 



