How Seedlings Get Established 



13 



older plants. They are very delicate, 



and it is better to grow the roots in 



moist air, to see the many minute 



root-hairs. On a seedling with root- 

 lets an inch or more long, notice 



that just back of the tip it is covered 



with a very fine fuzzy growth. This 



fuzzy growth is composed of thou- 

 sands of slender tube-like cells, 'called 



root-hairs. (Figs. 11 and 12.) 



They are formed near the root's 



tip. After a time they die. They 



cannot be found on the root except 



for a short way from the tip. Unless 



the soil is very carefully washed from 



the rootlets, the root-hairs may not 



been seen. (Fig. 11, B.) 



22. How the Root Absorbs Water. 



Even though the seedlings that have 



been growing in sand or sawdust be 



very carefully washed, much of the sand or sawdust 



adheres to the hairs. (Fig. 12.) The root-hairs hold the soil 



particles to the 

 root. When the 

 roots are growing 

 in moist air, they 

 are straight; but 

 in the soil the 

 hairs apply them- 

 selves very closely 

 to the soil parti- 

 Fig 12. Root-hairs of corn seedling with * ' ^' ' 

 soil particles adhering closely. The Water at> 



Fig. 11. Seedlings of 

 mustard. A, with 

 particles of soil cling- 

 ing to root-hairs. B, 

 after removal of soil 

 by a stream of water. 

 After Sachs. 



