receive seed from Baltimore, upon request. A new supply will 

 be available in the fall of 1919. 



The second plant to be studied is soy bean, and a supply of seed 

 has been made available through the kindness of Mr. J. E. 

 Metzger of the Maryland Agricultural Experiment Station. This 

 seed may also be obtained from Baltimore, on request. 



TWO METHODS OF CULTURE. 



It is planned to carry out this elaborate series of physiological 

 tests with both water and sand cultures, but it seems desirable to 

 press forward somewhat more rapidly with the former; most 

 workers may prefer to attack the water cultures first, since the 

 operations are simpler here. Both methods are set forth below. 

 Special details for soy bean and for the later phases of wheat 

 are still to be elaborated and modifications of the outline here 

 given may be required as the work progresses. 



WATER CULTURE OF WHEAT. 

 Four Developmental Phases. 



The development of the plant will be considered in four sepa- 

 rate stages or phases, three of these being defined by the degree 

 of development attained and the other by time duration. These 

 phases are as follows: 



1. Germination Phase, from beginning of soaking till the 

 shoot is four centimeters high, measured from the seed to the tip 

 of the shoot. 



2. Seedling Phase, from the end of phase 1 for a period of 

 five iveeks, without regard to the size of the plant. 



3. Vegetative Phase, from the end of phase 2 until the first 

 appearance of flowering in the controls. [Controls are always in 

 Shive's best solution for wheat seedlings, IR5C2, by 1/10-incre- 

 ments (1.75 atm.) ; see below.] 



Jf. Reproductive Phase, from the end of phase 3 until ma- 

 turity is reached by the best five cultures of the group of 20 or 21. 



These phases ghould be adhered to with care, in order that all 

 the parts of the work may be comparable. It may be that their 

 definition will require alteration after the work is well in hand, 

 but the definitions here given will serve for the beginning. 



It is aimed first to find out what four solutions should be 

 consecutively used to produce plants that are the best at the ends 

 of all four stages of development. Thus, after the plan has been 

 carried out we should be able to say that phase 1 should have 



10 



