340 Plant Physiology 



or branch in water at a temperature of from 30 to 35 C. 

 for a period of from 9 to 12 hours. When potted plants 

 are employed, it is preferable to invert the pot and im- 

 merse the stem portion only, since the roots are generally 

 more sensitive to injury. This method has certain prac- 

 tical advantages over etherization, and if as generally 

 successful, it will doubtless become important. The 

 changes brought about by this treatment have not been 

 determined. 



200. Transplanting after wilting. - - Practical truck 

 growers are often met who are in the habit of wilting cer- 

 tain seedlings before transplanting, claiming that plants 

 thus wilted recover promptly and grow off more vigor- 

 ously than others not so treated. Experiment seems to 

 confirm the practice for the tomato, and it may be sug- 

 gested, provisionally, that the effect is indirect. A rather 

 rough removal of tomato seedling from the seed bed 

 results in some injury to the rootlets and root-hairs. If 

 wilted, these roots do not recover upon transplantation, 

 and vigorous new roots are promptly developed under 

 suitable conditions. 



On the other hand, it appears that in the case of those 

 seedlings placed without wilting under more favorable 

 conditions for growth, the injured roots may recover slowly, 

 and generally new roots are not so promptly developed. 

 It may, perhaps, be inferred that any plants which do 

 not readily develop new roots, such as the lettuce, corn, 

 etc., would be greatly injured by the wilting process. It 

 seems certain that transplanting with so great a ball of 

 earth as not to injure the rootlets would be preferable in 

 all cases, except where the roots are so much entangled as 



