Impact of forest liming on growth and crown vigor of sugar maple and associated hardwoods

Abstract

Sugar maple (Acer saccharum Marsh.) has been declining across the unglaciated Allegheny Plateau in northwestern and north central Pennsylvania since the mid-1980s. A long-term study to evaluate the effects of fencing, herbicide, and liming on growth, crown vigor, and regeneration of sugar maple and associated Allegheny hardwoods was initiated in 1985. The study is a split-plot design with fencing (fence - no fence) as the whole-plot treatment and four subplot treatments: applications of herbicide (glyphosate) to control interfering vegetation, dolomitic lime (22.4 Mg.ha-1) to reduce soil acidity, dolomitic lime and herbicide, and an untreated control.