of fescue on both minesoils was 

 largely confined to the upper 3 cm 

 of the compacted column. The 

 fescue roots seemingly were not 

 able to fully exploit the clay mine- 

 soil at the highest compaction 

 rate. 



Sericea yields were reduced 

 drastically at the highest rate of 

 compaction on both minesoils. 

 Sericea yields were greater on the 

 clay than on the loam at 1.8 and 

 2.0 g/cm3 compaction levels. The 

 primary roots of sericea were found 

 to extend the full length of the 

 compacted column in both mine- 

 soils even at the highest density. 

 At higher compaction rates sericea 

 roots may have failed to branch 

 sufficiently, causing water and 

 nutrient deficits in the plants. 



The results of this study suggest 

 that the effects of compaction 

 may vary with the texture of the 

 reclaimed mine surface. The resist- 

 ance of the minesoil matrix to root 

 penetration is somewhat compen- 

 sated for by the ability of clay to 

 hold water and thus promote growth. 

 Probably, the increased water 

 holding potential of clay reduces 

 the rate of water loss with increas- 



ing compaction. Also, mitigating 

 factors such as selection of plant 

 species assist in offsetting the 

 effects of compaction. The com- 

 paction of the loam soil promoted 

 the increased yield of fibrous shallow- 

 rooted fescue. Moderate compaction 

 may be desirable to reduce minesoil 

 porosity and increase the volume 

 water content of the coarser tex- 

 tured soils. 



The results of greenhouse eval- 

 uations using containers should, of 

 course, be applied with caution to 

 field situations. Even though com- 

 paction may reduce or limit infiltra- 

 tion of water into the soil, water 

 added to greenhouse containers 

 will be retained on the soil surface 

 until it can soak in or evaporate, 

 thus supplying water to plants with 

 very shallow root systems. If watered 

 often enough, the plants will be 

 adequately supplied, whereas under 

 field conditions, water may not be 

 retained on compacted soils. Fine- 

 textured minesoils, when moderate- 

 ly compacted, are more subject 

 than coarse-textured soils to the 

 effects of runoff and erosion. How- 

 ever, moderate compaction of 

 coarser textured minesoils may aid 

 the establishment of vegetation. 



Literature Cited 



Allison, L. E. Organic carbon. In: 



C. A. Black, et al., eds. Methods 

 of Soil Analysis, Part 2. Agronomy 

 9: 1367-1378; 1965. 



Brady, Nyle C. The nature and 

 properties of soils. 8th ed. 



New York: Macmillan; 1974. 

 639 p. 



Day, Paul R. Particle fractiona- 

 tion and particle-size analysis. 



In: C. A. Black, et al., eds. 

 Methods of Soil Analysis, Part 

 1. Agronomy 9: 545-552; 1965. 



Flannery, Roy L.; Markus, D. K. 

 Determination of phosphorus, 

 potassium, calcium, and magne- 

 sium in North Carolina, ammon- 

 ium acetate, and Bray Pi soil 

 extracts by autoanalyzer. In: 

 L. M. Walsh, et al., eds. Instru- 

 mental Methods for Analysis of 

 Soils and Plant Tissue. Madison, 

 WI: American Society of Agronomy; 

 1971: 97-112. 



Taylor, S. A.; Box, J. E. Influence 

 of confining pressure and bulk 

 density on soil water metric 

 potential. Soil Science 91: 6- 

 10; 1961. 



The author is a soil scientist at 

 the USDA Forest Service, Northeastern 

 Forest Experiment Station, Forestry 

 Sciences Laboratory in Berea, 

 Kentucky. 



* U.S. GOVERNMENT PRINTING OFFICE: 1984—705-029/514 



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