To determine the effects of shade on biomass, carbon allocation patterns and photosynthetic response, seedlings of loblolly pine (Pinus taeda L.), white pine (Pinus strobus L.), red maple (Acer rubrum L.), and yellow-poplar (Liriodendron tulipifera L.) were grown without shade or in shade treatments providing a 79 or 89% reduction of full sunlight for two growing seasons. The shade treatments resulted in less total biomass for all species, with loblolly pine showing the greatest shade-induced growth reduction. Yellow-poplar was the only species to show increased stem height growth in the 89% shade treatment. The shade treatments increased specific leaf area of all species. Quantum efficiency, dark respiration and light compensation point were generally not affected by the shade treatments. Quantum efficiency, dark respiration, maximum photosynthesis and light compensation point did not change consistently between the first and second growing seasons. We conclude that differences in shade tolerance among these species are not the result of changes in the photosynthetic mechanism in response to shade.

Nitrogen deficiency frequently limits mine‐soil revegetation in the eastern USA. Application of organic amendments to these systems may provide a long‐term source of N and eliminate the need for repeated fertilization. A factorial experiment was conducted using lysimeters to determine the degree to which (i) organic amendments (control, 50 Mg ha−1 of whole‐tree wood chips, or 500 Mg ha−1 of native topsoil) and (ii) inorganic N fertilizer (0 or 100 kg N ha−1 as NH4NO3) affected mine‐soil properties and establishment of herbaceous vegetation and pitch × loblolly hybrid pine (Pinus rigida L. × P. taeda L.) seedlings on a newly exposed mine soil from the central Appalachian region. Amendments were tilled into the soil surface prior to application of fertilizer and cover‐crop seed. After 3 yr, total N, mineralizable N, and organic C in the wood‐chip‐amended mine soil were 10, 50, and 18% higher, respectively, than the control. Tree growth after 2 yr was highest with wood chips. A lack of wood‐chip treatment effect on pine nutrition showed that higher soil moisture levels, resulting from lower evapotranspiration, probably accounted for improved tree growth. Topsoil replacement increased total N and mineralizable N by 23 and 46%, respectively, but did not significantly increase vegetation productivity over that of the control. Nitrogen fertilizer increased herbaceous biomass production by 87% during the first growing season but did not affect herbaceous or pine productivity in two subsequent years or produce lasting effects on soil nutrient levels. Organic amendment × fertilizer interactions were not significant for any measured parameters. Results show that the organic amendments provided more stable sources of soil N; however, early revegetation success was more a function of moisture than of soil nutrient availability.

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Herbicide treatments were made to the cambial area of Piedmont hardwoods immediately after chainsaw clear-felling using Roundup® Velpar L ®, Tordon 101R®, Garlon 3A®, and Banvel CST®. Evaluations of the materials used were based on both percent kill of treated stumps and percent control of sprouting. Efficacy was determined for stumps treated during the dormant and growing season and for those growing on good versus poor sites. The interaction between herbicide and season of harvest was significant, with Tordon 101R, Velpar L, and Banvel CST all performing better on the dormant season-harvested areas. Garlon 3A and Roundup gave slightly better control of sprouting on the growing season-harvested areas. Based on percent kill, the Roundup, Garlon 3A, and Tordon 101R treatments were significantly more effective in controlling resprouting than the Velpar L and Banvel CST treatments. Two years after treatment, plots receiving the herbicide treatments had significantly less hardwood competition present. The hardwood basal area averaged 16.1 ft²/ac on untreated areas as opposed to 7.0 ft²/ac on the stump treated areas. South.J. AppL For. 11(1):46-49.