Table \. --Relative weight of roots in various soil layers 7.5 

 am. thick. (A substantial portion of the fine roots 

 is not included in these values)^ 



Layer 



; Depth 





: Units in : 

 : sample : 



Weight 



with 



std. error 





— Cm. 









-G./m. 



2 



I 



0-7, 



.5 



6 



77, 



. 1±30. 



7 



III 



15.0- 22. 



,5 



6 



76. 



.0± 7. 







V 



30.0- 37, 



,5 



6 



63, 



.3±13. 



3 



VII 



45.0- 52, 



,5 



6 



45, 



,2± 7. 



7 



IX 



60.0- 67, 



.5 



7 



28. 



,6± 6. 



8 



XI 



75.0- 82, 



,5 



3 



23. 



,2± 7. 



7 



XII 



82.5- 90, 



.0 



2 



3. 



.3± 1. 



3 



XV 



105.0-112, 



,5 



2 



2. 



.7± 1. 



7 



■^Area of sampling unit: 0.092 m.^ 



Table 2. --Mean weights , with standard errors, of roots and underground litter in 

 the first three 7.5-om. layers helow the ground surface^ 



Layer \ Coarse roots ' Medium roots Fine roots \ Total roots ' Underground litter 

 G./m.^ 



I 2i22.0±46.2 17.0±3.0 26.9±2.3 165.9±48.2 177.2±16.5 



II 15. 3± 6.1 28.2±2.4 130.4±4.4 173. 9± 9.2 29. 2± 3.5 



III 4.8± 1.9 26.311.3 121.2±3.7 152. 3± 4.7 20. 9± 1.4 



■^Area of sampling unit: 0.0113 m.^; 90 units in each sample. 



^Underground shoot parts of grass comprise 2.8 percent of weight of coarse roots 

 in layer I. 



Table Z .--Coefficients of variation (standard deviation t mean) of 



root weights'^ 



Layer ' Coarse \ Medium ' Fine ' Total roots 



Percent 



I 357 164 81 274 



II 377 81 32 50 



III 373 46 29 29 



■^Area of sampling unit: 0.0113 m.^. 



