SOUTH INDIAN GRASSES 



The root-system. — The root-system of grasses is very striking 

 in its character. In most grasses, especially in erect ones, several 

 roots all of about the same diameter arise in a dense tuft from 



. v _. __ ^ nearly the 



same level 

 and from the 

 lower-most 

 nodes of the 

 stems. The 

 roots are all 

 thin and 



fibrous in the 

 vast majority 

 of these 



plants, and 

 they are 



tough and 

 wiry only in 

 a few cases 

 such as in the 

 case of the 

 roots of Penni- 

 setum cen- 

 chroides, P. 

 Alopecuros, 

 Ischcemum 

 pilosum and 

 Andropogon 

 Schoenanthus. 



On a close 

 examination 

 it will become 

 ' evident that 

 all the roots 

 of a grass 

 plant are 



t „ u a .i r , . adventitious. 



Inasmuch as the growth of the primary root is soon overtaken bv 

 other roots growing from the stem, all the roots happen to be of the 

 same size. Roots arise from the nodes just above the insertion of 

 the leaf, and they grow piercing the leaf-sheath. 



Grasses in which stolons and prostrate branches occur have in 

 addition to the usual radiating crown of roots at the base aerial 

 roots growing out of the upper nodes of the branches and fixing 

 them to the soil. Such roots become supporting or prop roots and 

 «e Particularly conspicuous in several stout tall grasses such as 

 Andropogon Sorghum, Zea Mays and Pennisetum typhoideum. (See 



All the roots bear branch-roots which originate from the inner 

 portion of the mother roots in the usual manner. The character 

 and the extent of the development of the root-system is to a laree 

 extent dependent upon the nature of the soil and its moisture 

 content. In light dry soils roots remain generally stunted and in 



Fig. 6. — Panicum Crus-gallj, 



