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Physical and chemical properties of minesoil reclaimed for forest land use in southwestern Indiana were evaluated to determine suitability for reforestation according to specifications of Public Law 95–87, The Surface Mining Control and Reclamation Act of 1977. Properties of reconstructed minesoil and unmined reference soils were compared. Soil types on the reference area were primarily Ava (Typic Fragiudalf) and Parke (Typic Hapludalf) silt loams and were similar to soils on the mineland prior to excavation. Both the reclaimed mineland site and reference site supported mixed upland hardwood trees and shrub vegetation prior to surface mining. Chemical properties of minesoil were similar to or more favorable for plant growth than unmined reference soils. However, physical properties in the rooting zone were less favorable in minesoil than reference soils. Minesoil had higher bulk density, lower porosity, lower permeability, higher coarse fragment and clay content, and lower available water‐holding capacity than reference soils at comparable depths. Mean bulk density of minesoil, adjusted for rock fragments > 2 mm, ranged from 1.53 Mg m−3 (g cm−3) in topsoil to 1.77 Mg m−3 in graded cast overburden. Mean available water‐holding capacity was 16.5% in topsoil and 10.8 to 11.7% (kg kg−1) in graded cast overburden layers of minesoil. Chemical properties of minesoil should be adequate for cover crop and tree seedling establishment after liming and fertilization to recommended soil test levels of NPK. However, physical properties could adversely affect plant survival and growth.

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One concern of short-rotation intensively cultured hardwood plantations is the accelerated loss of nutrients due to removal of large amounts of biomass and short harvest cycles. In this study, we examine simultaneously the nitrogen trends in all the various pools (trees, weeds, soil, and soil water). We compare the N trends and fertilization rates with leaf N status and tree growth on two soil types over 5 years. The data show a gradual transition from an early herbaceous plant dominated system to a tree-dominated system later in the rotation. On the more fertile site, fertilization was not beneficial to tree growth the 1st year, or even the 2nd, if all weeds were kept out. However, when weeds were present, fertilization was very beneficial to tree growth in the 2nd and 3rd years. After crown closure, fertilization declined in importance as herbaceous vegetation was eliminated, tree foliage biomass stabilized, and N cycling increased. Foliar N was strongly related to fertilizer rate during years 2 and 3 on the fertile site and during the entire 5 years on the infertile site. Form these relations and others, we infer possible critical times for N fertilization during the first 5 years of a rapidly growing hybrid poplar plantation from the time of initial planting through complete canopy closure and shading out of the herbaceous competition.

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