192 BOARD OF AGRICULTURE. 



of the giraffe is mainly the buds and twigs of a kind of locust tree 

 that grows in the African wilderness, and the long fore-legs and 

 long neck of the animal are shaped for browsing among the tops 

 of those trees. The different classes of plants have peculiarities 

 in their feeding arrangements which are as marked and striking 

 as these differences in animals. , 



On comparing together the roots of our ordinary crops, we find 

 that when they grow under similar circumstances there is o great 

 difference in the depth to which they extend, a great difference 

 in the degree in which they branch, and a great difference in 

 the absolute quantity of roots. Unfortunately, we have not 

 enough really satisfactory observations on these points to serve 

 us in any very extended comparison, it being rather troublesome 

 to make accurate observations of the roots of plants when they 

 have once penetrated the soil. A few brief paragraphs in my 

 book "How Crops Grow," embrace pretty nearly all we know 

 about this matter of the growth of roots. As to depth, Schubart 

 has made the most satisfactory observations we possess on th-3 

 roots of several important crops growing in the field* He sepa- 

 rated them from the soil by the following expedient : an excava- 

 tion was made in the field to the depth of six feet, and a stream of 

 water was directed against the vertical wall until it was washed 

 away, so that the roots of the plants growing in it were laid bare. 

 The roots thus exposed in a field of rye, in one of beans, and in a 

 bed of garden peas presented the appearance of a mat or felt of 

 white fibers to a depth of about four feet from the surface of \he 

 ground. Roots of winter wheat were observed as deep as seven 

 feet. in a light sub soil, forty-seven days after sowing. The depth 

 of the roots of winter wheat, winter rye, and winter coleseed, as 

 well as of clover, was three to four feet." Schubart further col- 

 lected and weighed the roots of wheat, rye, and peas, and ascer- 

 tained their proportion of the entire plant Hellriegel has also 

 published some observations on the extent of the roots of barley 

 and oats. 



We have a few other observations of this sort, but not enough 

 to enable us to determine the comparative quantity and depth of 

 the, roots of our cultivated plants with any accuracy. It will not 

 do to draw conclusions as to the length of roots from such ob- 

 servations as these, made, it would appear, in different soils, dif- 

 ferently treated and fertilized, because other observations show 

 that the development of the root depends not exclusively upon 



