ALFALFA EOOT STUDIES. 7 



ing through the soil remains restricted, and after grooving in the 

 field for several months the plants can be easily pulled out. The 

 effect of transferring seedlings of Grimm, alfalfa, 40 days old, to 

 flowerpots for a period of 39 days is shown in Figure 5. These 

 plants were taken from the drilled row on June 24, 1920, and put 

 in small pots which were set in the ground. On August 2, 1920,. 

 the flowerpots were broken, so that the roots were permitted ta 

 spread through the soil. The plants were removed from the field 



Fig. 4. — Eeset plant of yellow-flowered alfalfa (Medicago falcata), showing the very 

 extensively branched root system. 



land photographed on October 19*. Such treatment appeared to pro- 

 iduce distortions of the roots and to promote the growth of many 

 more branches. The effect of limited space for root development on 

 young plants is again illustrated in Figure 6. In this case Grimm 

 alfalfa was sown in small pots on June 24, 1920, and the pots set in 

 the ground. The young seedlings were thinned to one plant to each 

 pot and permitted to grow in this limited area until August 2, when 

 the pots were broken, permitting the roots to spread through the soil. 

 Although the growth of these plants was less than that of the older 

 seedlings (Fig. 5) which were transplanted from the field to the 

 pots, nevertheless the roots showed the same tendencies toward 



