30 



MUSIC. PUBLICATION 3 6 9, U. S. DEPT. OF AGRICULTURE 



Table 11.— Mineral composition of soybean -plants {above-ground portion) 1 grown 



in Michigan 



[Austin (37)] 



Stage of growth and soil type on which 

 grown 



K 



Ca 



Mg 



P 



S 



35 days after seeding (July 13): 

 Hillsdale sandy loam . 



Percent 

 0.695 

 .635 

 .504 

 .812 

 .663 



Percent 

 2.702 

 2.162 

 2.799 

 2.081 

 2.370 



Percent 



0.586 



1.083 



.694 



.663 



.832 



Percent 

 0.234 

 .469 

 .411 

 .345 

 .312 



Percent 

 0.232 





289 





.318 





.275 





.258 









.662 



2.423 



.772 



.354 



.274 







73 days after seeding (Aug. 19) : 



Hillsdale sandy loam. ._ ... 



.722 

 .627 

 .729 

 .623 



.774 

 .511 



2.050 



1.792 

 1.760 

 1.813 

 1.834 

 1.894 



.846 

 1.086 



.644 

 - .643 



.773 



.665 



.287 

 .374 

 .403 

 .383 

 .242 

 .377 



.283 



Brookston clay loam . 



.291 



Coloma sand ._. _____________ 



.321 





.236 





.260 





.347 









.664 



1.857 



.776 



.344 



.290 







110 days after seeding (Sept. 26): 

 Hillsdale sandy loam 



.576 

 .713 

 .591 

 .738 

 .532 



1.865 

 1.681 

 2. 115 

 1.294 

 1.291 



.719 

 .795 

 .607 

 .536 

 .637 



.329 

 .390 

 .462 

 .423 

 .280 



.249 





.326 





.286 





.277 





.229 









.630 



1.649 



.659 



.377 



.273 







Averages for each soil: 



.664 

 .658 

 .608 

 .724 

 .656 



2.206 



1.878 

 2.225 

 1.729 

 1.832 



.717 

 .988 

 .648 

 .614 

 .747 



.283 

 .411 

 .425 

 .384 



.278 



.255 





.302 





.308 





.263 





.249 







i Moisture-free basis. 



Fonder in 1929 investigated the composition of the leaves and 

 stems of several plants grown in different soil types in different areas 

 in Michigan, and he attempted to correlate his data with the com- 

 position of the soil solutions (188, 189, 190, 191). Some of his data 

 are presented in table 12, because they show how the mineral composi- 

 tion of one part of the plant may vary when the plants are grown in 

 different soils. The data for alfalfa leaves only are given here, but 

 the discussion would also apply to the composition of the stems of 

 alfalfa or of leaves and stems of the green bean plant or pea plant 

 which Fonder also studied. The data show that alfalfa leaves grown 

 in the Plainfield loamy sand contain less calcium than the average 

 throughout the growing season, while those growing in the Fox sandy 

 loam contain more than the average. The average calcium through- 

 out the season in the plant leaves growing in the Plainfield soil is 

 1.648 percent, and that of the plant leaves growing in the Fox soil is 

 2.609 percent, a significant difference. The magnesium in the plant 

 leaves grown in the Brooktons loam is low throughout the season, in 

 contrast with the data of Austin (table 11), while that in plant leaves 

 grown in the Fox sandy loam (table 12) is high. The potassium 

 data are not so consistent throughout the season, but well-defined 

 trends are observable. The data show also that calcium accumulates 



