46 



WILTING COEFFICIENT FOE DIFFERENT PLANTS. 



Table XIII. — Wilting- coefficient determinations in soil No. 30 (fine sandy loam), 

 moisture equivalent 18.5, for different plants grown simultaneously in the same pot 

 with Kubanka wheat — Continued. 



Plant species or variety. 



Coeffi- 

 cient. 



Mean. 



Comparison with. Kubanka wheat. 



Amaranthus retroflexus 



9.1 

 9.7 

 11.0 

 9.4 

 9.6 



10.2 

 9.8 

 10.1 



9.3 

 10.7 

 10.0 

 10.9 

 10.7 



9.9 



9.8 

 10.0 



10.3 





Do 





Do 





Do 





Do 



"Wilted simultaneously. 





Do 





Do 



Do. 



Artemisia gnaphalodes 





Do 





Do 





Do 





Do 





Do... 



Do. 







For all determinations, soil No. 30. 



9.7 



± .02 

 ± .04 





Probable error of mean 







Probable error of single observa- 







tion. 







Table XIV. — Plants grown simultaneously in the same sealed pot with Kubanka wheat, 

 G. I. 1440, but no soil-moisture determinations recorded. 



Plants. 



Water cress 



Ranunculus septentrionalis 



Ranunculus abortivus 



Acorus calamus 



Peltandra virgmica 



Bamboo 



Datura stramonium 



Adiantum pedatum 



Polystichum acrostichoides 



Hepatica triloba 



Salixsp 



Heteranthera reniformis 



Allium cepa 



Notes. 



8 Wilted simultaneously. 



Do. 



Do. 

 Wheat wilting; flag dying back. 

 Wilted simultaneously. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 

 Wheat wilting; onion dying back. 



The results obtained by the method of simultaneous culture are 

 in practical agreement with the determinations already discussed, as 

 will be seen by referring to Tables XIII and XIV. 



In nearly every instance the plant under observation wilted simul- 

 taneously with the wheat growing in the same pot. The corn showed 

 a little more discoloration than the wheat in some instances, while 

 in the case of the sorghum the leaves did not roll quite so much as the 

 wheat. The emmer showed a tendency to roll more than the wheat. 

 With the remainder of the plants tested the wilting occurred simul- 

 taneously with the wheat, as nearly as could be determined. 



A single wheat seedling was used in each pot. Since the root dis- 

 tribution of this seedling was not sufficient to permeate the whole 

 mass of soil, we would expect the wilting-coefficient determinations 

 to show in a modified degree the differences exhibited by coarse- 



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