Results and Discussion 



Growth and yield data for fescue 

 and sericea are shown in Table 2. 

 Plant height of both species gen- 

 erally decreased with increased 

 compaction. Height and growth of 

 sericea were more adversely affect- 

 ed by increased compaction than 

 was the growth of fescue. The 

 yield data for the greenhouse pots 

 were subjected to analysis of vari- 

 ance (Table 3). Treatments were 

 considered to be factorial sets of 

 density and species. A split plot 

 with blocks nested in textural types 

 was used to evaluate the data. 

 Texture and compaction significant- 

 ly influenced the final dry matter 

 yield of both fescue and sericea. 

 The interaction of texture and 

 compaction also proved to be signif- 

 icant. With one exception, 

 yield of both species decreased at 

 the highest level of compaction 

 (2.Q g/cm 3 ). Fescue yields on the 

 loam increased with increased 

 compaction (Table 2) even though 

 plant height decreased. With the 

 exception of sericea yield on loam, 

 yields of both species increased at 

 the first increase in compaction 

 (1.6 g/cm 3 to 1.8 g/cm 3 ). Total 

 dry mass production of both species 

 was greater on clay than on loam 

 (456.3 g vs. 381.2 g). 



The moisture retention capabil- 

 ity of the loam seemed to improve 

 with increasing compaction to 

 promote better growth of fescue. 

 Increased growth at the highest 

 density (2.0 g/cm 3 ) indicates that 

 water and nutrients both were 

 available for plant growth. The 

 closely packed loam reduced the 

 normal minesoil porosity and main- 

 tained moisture in a form readily 

 available to fescue roots. This 

 agrees with findings of Taylor and 

 Box (1961) that an increase in avail- 

 able soil moisture went with an 

 increase in compaction on a silt 

 loam soil. Fescue yield decreased 

 at the highest level of compaction 

 on clay minesoil. Root development 



Table 2.— Plant height and yield data 



Species Compaction Plant Heights 



Yield b 







Loam 



Clay 



Loam 



Clay 





g/cm 3 















■cm 





g 



Sericea 



1.6 



73.5 



78.4 



51.65 



50.74 



Sericea 



1.8 



65.4 



61.5 



25.37 



60.94 



Sericea 



2.0 



21.3 



27.1 



16.12 



23.44 



Fescue 



1.6 



47.4 



41.6 



81.87 



111.59 



Fescue 



1.8 



46.9 



39.6 



92.01 



114.63 



Fescue 



2.0 



40.6 



41.6 



114.21 



91.96 



a Height is averaged among three replications, 

 were taken immediately prior to harvest. 



Measurements 



^Yield is total amount of oven-dry plant material at each 

 compaction rate. 



Table 3.— ANOVA table for plant yield 



Source 



DF 





ss 





MS 





Observed F 



Texture (T) 



1 



11. 



,773. 



82 



11,773 



.82 



115.34* 



Block in T (B) 



4 





408. 



34 



102 



.08 





Treatment (R) 



5 





732. 



78 



146 



.56 



4.98* 



TR 



5 



11: 



,457. 



68 



2,291 



.54 



77.86* 



BR in T 



20 





588. 



69 



29 



.43 





♦Significant at the .01 level 



4 



