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species outnumbered annual species by fourteen to six. Seasonality of 1987 • Reclamation Area species was split between cool season, warm season, and deciduous species. Graminoids were evenly split, six were cool season, and six were warm season species. With the exception of He/ianthus annuus, all forb species were identified as cool season. The shrub species was deciduous. Eight species (six grasses and two fortis) represented greater than three percent relative cover. These species included Calamovilfa longifolia (48.96%), Bouteloua graci/is (9.50%), Bromus marginatus (8.01%), Agropyron cristatum (6.53%), Agropyron smithii (4.45%), Mdropogon hallii (3.26%), Helianthus annuus (3.26%), and Kochia scoparium (3.26%). COMPARISON OF RECLAIMED AREAS AND REFERENCE AREA Evaluation of revegetation success was accomplished through comparisons of the 1985, 1986, and 1987 Reclamation Areas with the Osgood Sand Reference Area as required by the approved CDMG permit. The reclaimed areas and reference area were quantitatively compared with regard to mean total vegetative cover. A standard was established for species composition and there is no requirement for establishment of woody plants in the 1985, 1986, and 1987 Reclamation Areas. A Students-t test was used to compare equivalency of the 1985, 1986, and 1987 • Reclamation Areas and the Osgood Sand Reference Area for the parameter of total vegetation cover. The form of the Students-t parametric statistical test used is as follows: Q.9XZ - Ri t= Sxl_XZ where: t =the Student's t distribution value X I = the sample mean from the reclaimed area X2= the sample mean from the reference area Sx t _xZ =the standard ertnr of the difference between the means If the t value calculated from the sample information is less than the table t value, the hypothesis that the sample means are equal is accepted. With regard to comparisons of the reclamation areas and reference area, a calculated t value less than the table t value indicates that there is no significant difference between the total vegetation cover on the reference and the reclamation area. -10.