Search

Sugar maple (Acer saccharum Marsh.) decline disease, decreased growth, and regeneration failure have been related to a low supply of Ca and Mg. There is increased interest in augmenting cation availability via liming, but there is little information on the amounts of lime required and the longevity of the lime treatment. A single application of 22.4 Mg ha-1 of dolomitic limestone in 1985 at four forested sites in Potter County, PA has shown that soil, soil water, and sugar maple foliage chemistry are significantly altered by liming and the changes in soils and foliage persist as long as 21-yr post-treatment. By 2001, only 3 kg ha-1 of lime remained undissolved while increases in exchangeable Ca and Mg, and pH continued through 2006 at depths up to 35 to 45 cm. Exchangeable Mn and Al concentrations were significantly reduced by lime application, though effects were slower to develop at deeper depths. Soil solution chemistry from 1996 was highly variable but reflected the changed soil nutrients. On limed plots, sugar maple foliage had elevated concentrations of Ca and Mg in 2006 samples, indicating the persistence of the lime treatment. Comparison of Ca/Al ratios in soil solution, soils, and foliage show inconsistencies from previous published risk thresholds. Species-specific thresholds of Ca and Mg availability in soil and foliage have better potential management application and should be more rigorously tested as stress indicators. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to determine the relationship of factors that affect health and growth of Sugar maple Acer saccharum in the northeastern U.S. It assesses the presence of nutrients such as calcium (Ca), magnesium (Mg), and manganese (Mn) through foliar and soil analysis. It shows that the growth of the maple tree as manifested by basal area increment (BAI) estimates were largely influenced by the presence of Mg and Ca in spite of the absence of defoliation process.

The article discusses the study on the management of white-tailed deer found at the forest sites of northwestern Pennsylvania which causes damage on forest vegetation, crops, and wildlife habitat. It shows their is no negative effects on vegetation despite of deer densities but species resilient to browsing have indirect effects on plants.

Presents a letter to the editor in response to comments made on the thirty years of change in forest soils of the Allegheny Plateau, Pennsylvania.