5<$ 



hence predetermined ty the internal conditions of the seed, 

 Within the range cf enviroruaental conditions encountered in 

 this study it appears th^-t the taller and more leafy the plant 

 "becomes in the firs' ^ eek.o -. 1 growth, the lower is tlie v -lue 

 of the ratio of final height to final foliar expanse. The two 

 growth nrocesses here considered are therefore clearly inter- 

 relate i «u that ilieither one alone is to be regarded as a cri- 

 terion of plant growth in general. In the cases here s'^'udied 

 it may be o f value to consider the average of these two indices 

 as a tentative index of the general growth -^* ■^'-"^ -^lants during 

 the first ty;o weeks from tiie seed, and inspection of the 2- 

 werk graphs leads to the impression that averaging the two values 

 is the most promising way to obtain :from them a single index of 

 plant growth. The tv/o graphs are always so nearly parallel 

 throughout the season at all stations here dealt with fnearly 

 coinciding for many periods, ai las been stated) that the charts 

 have not been further complicated by intro 'ucing these average 

 graphs, but their form is readily appreciated from the two 

 graphs that t.re given. Still another possible way to obtain a 

 single index for the growth-behavior of the plant as a whole 

 may be obtained by determining the ratio of the 2-week rate of 

 stem elor.-' "^^ "^a to the corresponding rate of Itict.' -ijru.iu.it in- 

 crease. 



The general relation between the two plant values, upon 

 which t: e discussion just given ia based, does not alwa- s hold, 

 however, and tiie following more detailed discussion of the 

 plant graph forms for .individual stations will be o-f' v;lue in 

 showing the main exceptions. As has been mentioned, for Oakland 

 the height value lies above that eaf-product throughout 



