26 



FIEST STUDIES IN PLANT LIFE 



look with a lens at the roots. On the well-drained 

 roots you will find hundreds of tiny feeding hairs, 

 while on the badly-drained roots these feeding hairs 

 will be absent or few in number. No wonder the 

 wheat in a wet patch of ground has a starved look ! 

 5. How the hairs on the root take in food. The 

 hairs on the root are, as we saw, 

 delicate cells that suck in water. 

 Now these hairs will not grow in soil 

 that is kept constantly wet. Hence 

 the poor growth of wheat in wet, badly- 

 drained soil. In warm, loose, moist 

 soil, on the other hand, the number of 

 roots and rootlets and root-hairs is 

 astonishing. Every particle of soil 

 seems to be searched. A large mar- 

 row, growing in such soil, was found 

 to have roots which, if put end to end, 

 would have measured over 15 miles ! 

 6. Plants that thrive in wet 

 ground. But here you ask me : 

 " Why, then, do some plants thrive in 

 sodden ground, and even in water ? " 

 Well, you must never forget that Nature has no vacant 

 plots in her great Earth-garden. Every patch of 

 ground is turned to account to support hfe of some 

 kind. And so plants have been gradually trained for 

 wet soils and for ponds. You may see on the margin 

 of a pond a grass, or reed, or tree that likes to have 

 its roots always in sodden soil. Further in, you find 

 a plant that likes to have its feet in water and its stem 

 in the air ; and, still further in, you see a plant that 

 likes to have both stem and root in water. 



Outer skin of root 

 ■with root-hairs 

 (much enlarged), 

 showing that the 

 hairs are simply 

 extensions of cells. 



