THE WHEAT CIILTTIEIST. 



51 



serve to show something of the habit of wheat. Every 

 kernel sends out numerous long roots and rootlets, as 

 represented bv the figure. The kernel was buried about 

 one inch deep. The longest leaf was about four inches 

 long when the sketch was made. The roots which 

 spring from the kernel are called the primary roots. 

 At A, a little below the surface of the soil, is a ring, or 

 bulb, in the stem, from whence the coronal, or secondary 

 roots spring, which all spread out horizontally ; while the 

 primary roots strike downward as far as the soil has been 

 pulverized ; and where the subsoil is not compact, the 

 roots frequently grow from one to four feet below the 

 stratum of soil moved by the plough. 



Here is a point of eminently practical importance to 

 wheat-growers, which will be explained more fully under 

 the heading of the Advantages of Drilling in the Seed, 

 viz. : when the grain is deposited from one to two inches 

 deep, the primary roots, which issue from the kernel, 

 and the secondary roots springing from the joint A, are 

 so near each other that freezing and thawing of the soil 

 is not so liable to injure the plants during a mild winter 

 or late spring, as the numerous roots and fibres hold the 

 soil in a kind of mat, which prevents the frost from 

 heaving out the young plants. 



The habit of the wheat plant is further illustrated by 

 the accompanying figure of a wheat plant which 

 sprang from a kernel planted six inches below the sur- 

 face. The leaves, it will be perceived, appear slender 

 and not so strong and luxuriant as those of the pre- 

 ceding plant. There is a plausible and philosophical 

 reason for it. The substance which composes the kernel 

 is transformed into the primary roots and stem. If the 

 kernel is small, and is buried deep, there is sometimes 



