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• Historically, seeding rates for establishing vegetation on reclaimed mine sites were based on a <br />combination of this range restoration work and agricultural practices for grain or row crops used <br />in the more humid mid-westem and eastern United States. Agricultural seeding rates were based <br />on pounds or bushels of seed per acre that were designed to maximize crop yields. Nominal <br />consideration was given to seed size, germination, and purity; life cycle; active growth period; or <br />seed distribution when they were adapted to reclamation plantings on western mines. These <br />seeding rate practices have been carried over to reclamation of lands disturbed by road <br />construction, mining, fire and other large disturbances. <br />Typically, early seed mixtures for reclaimed rangeland had relatively few plant species. <br />Generally, plant available soil moisture and precipitation were adequate to allow seed to be <br />drilled in rows at fairly high seed density. These planting methods most frequently resulted in <br />mono-cultural stands of aggressive cool-season grass species. These cool-season grass stands <br />were effective in reducing weed infestations, but their biologic diversity was low and the stands <br />were more susceptible to disease (R. McGuffin, 1987). <br />One of the first modifications to this high density seed rate/low species diversity seed mix <br />mentality finally came in 1968 with the publication of "Restoring Big-Game Range in Utah" by <br />Plummer, Christensen and Monsen. They compiled more than 10 years of reseazch initiated by <br />the Utah Fish and Game and the USFS in 1955 to determine the methods to stabilize watersheds <br />and improve range productivity. Their reseazch determined that seeding rates of 8 to 10 pounds <br />of seed per acre was adequate to establish a good stand of native grass, forb and shrub species if <br />• the seeds were of acceptable purity and viability (Plummer et al., 1968). This seeding rate is <br />estimated to be approximately 18 seeds per square foot. These reseazchers initiated the concept <br />of Pure Live Seed ("PLS"). PLS is determined by multiplying the purity by germination and <br />dividing by 100. For example, if purity of a given seed sample is 95 percent and germination is <br />80 percent, the PLS would be 76%. Seeding rates on sites with less than 12 inches of <br />precipitation were applied at rates approximately 25 percent lower than sites with more than 12 <br />inches of precipitation or approximately 13.5 seeds per square foot (Plummer et al., 1968). <br />Since the late 1970's, coal mine reclamation has been mandated by various state and federal laws <br />(SMCRA, 1977). These laws required the establishment of a diverse cover of native vegetation. <br />Initially, vegetation plantings focused on establishing a thick cover that protected the soil from <br />erosion while having the ability to produce significant amounts of forage for livestock use. Seed <br />mixtures and application rates on western acid and semi-arid lands continued with established <br />traditions resulting in reclamation with acceptable cover and productivity, but dominated by <br />aggressive cool-season grasses and low species diversity. <br />As these mining laws have been adapted to western arid and semi-arid reclamation in the last two <br />decades, increased focus has been placed on the establishment of vegetation communities on <br />reclaimed lands that have higher biodiversity. This focus includes diversity within and between <br />vegetation communities. In response, reclamation reseazch has begun studying the issue of <br />species diversity and seed mix composition and rates. Recently, Munshower (2000) published <br />what many field-experienced reclamationists have observed during their years of reclamation <br />• Appendix G 8 06/28/02 <br />