Root Biomass on Native Range and Mine Spoils in Southeastern Montana

Abstract

Research was conducted on native range and revegetated strip mine spoils near Colstrip, Montana, in August of 1975 to determine the weight and distribution of root biomass at five locations. Study sites included native range in excellent, good, and poor condition; a naturally revegetated 40-year-old leveled, ungrazed strip mine spoils; and a 5-year seeded and fertilized mine spoils. Total root biomass was highest on the 5-year-old seeded and fertilized mine spoils. Good condition native range had a higher root biomass than excellent or poor condition native range. The root biomass of the 40-year-old mine spoil did not differ from excellent condition native range. Root biomass distribution in the four zones studied did not differ between sites. Over 55% of the root biomass was in the upper 15 cm of the soil profile at all five locations.