Methods to determine vegetation production on surface mines

State regulatory authorities (SRAs) must evaluate the amount of 1) plant cover and 2) production on revegetated areas and compare them to reference areas or a technical standard to determine if acceptable vegetation exists for reclamation bond release. While most SRAs have adopted a method to evaluate ground cover by plants, only a few SRAs have established a method for determining production. In this study, six methods for predicting aboveground biomass were used to determine if one or more methods would provide an accurate way of assessing aboveground biomass. Correlations were determined between each of six methods and the dry weight of forage clipped from large (65 m ) plots on eight reclaimed sites in West Virginia. Three methods involved visual estimations (quadrat cover, estimated yield, and average height), two methods involved indirect measurements (disk height and probe), and the sixth method used small plot clipping. The visual estimations were made by three individuals and their estimates were analyzed for variance among observers. Results showed significant differences among the observer's estimates indicating that these estimation methods would not be dependable for determining revegetation success. Disk height, and averages of average height and estimated yield were significantly correlated with forage dry weight from large plots (r = 0.82 to 0.87), while cover and probe readings had r vlaues of 0.44 and 0.51, respectively. Small plot clipping (quadrat weight) was highly correlated to field yields (r = 0.85) and especially on five out of eight sites, but overestimated field yields by 35%. Disk height and small plot clipping were the only two methods used in this study that may be recommended for evaluating aboveground biomass for revegetation success.