Growing Media 



Premining: Infertile fine san- 

 dy soils and sandstone 

 rock outcrops; sodium 

 absorption ratio is 1 on 

 unmined topsoil and 10 

 on reshaped spoils; pH 

 6.9-8.0; no toxic condi- 

 tions. 



Postmining: Loamy clays 

 and sandy clay loams 

 containing stone: 



Premining: Pinyon-juniper woodland; big sage- 

 brush, snakeweed, fourwing saltbush, rabbit- 

 brush, galleta, Indian ricegrass, blue grama, 

 broom snakeweed, sand dropseed, fescue, and 

 prickly pear. 



Postmining: Only revegetated area (1978) limited to 

 Russian-thistle with scattered grasses, sweet- 

 clover, alfalfa, Indian ricegrass, blue grama, and 

 fourwing saltbush due to overgrazing by sheep. 

 Areas now fenced. 



Species Diversity 



Premining: Probably 

 more than 20 

 species. 



Postmining: About six 



species. 



Produaivily 



Premining: 12^32 lbs/acre for 

 native vegetation (excluding 

 pinyon-juniper). Heavily 

 overgrazed, potential not 

 estimated. 



Postmining: Revegetation lim- 

 ited; area subject to severe 

 overgrazing. 



Premining: Clay to sill 

 loams; sodium absorp- 

 tion ratio as high as 19; 

 pH 6-7 on unmined 

 areas, 5.3-8.1 on mined 

 areas. 



Postmining: Mix of rubble, 

 soil, and rocks; blown-on 

 straw mulch. Topsoiling 

 began in 1978. 



Premining: Primarily pinyon-juniper, big sagebrush, 

 blue grama, galleta, western wheatgrass, Indian 

 ricegrass, and needleandthread. 



Postmining: Fourwing saltbush, sagebrush, and 

 western and crested wheatgrasses. Some saltbush 

 are volunteer seedlings. 



Premining: 163 species. Premining: No data. 



Postmining: Natural 

 succession on raw 

 spoils; 72 species (34 

 maximum on one 

 plot), mostly in- 

 troduced annuals or 

 native herbaceous 

 plants and a few 

 saltbush; Russian- 

 thistle dominant. In- 

 itially one species 

 planted (crested 

 wheatgrass). As of 

 1978, new seed mix- 

 tures being tried. 



Postmining: Highly variable with 

 location and aspect — north 

 slopes produce much more 

 than south slopes. 



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