Forest Sciences Commons^™

The Ecological Significance Of The Herbaceous Layer In Temperate Forest Ecosystems, Frank Gilliam

Frank S. Gilliam

Despite a growing awareness that the herbaceous layer serves a special role in maintaining the structure and function of forests, this stratum remainsan underappreciated aspect of forest ecosystems. In this article I review and synthesize information concerning the herb layer’s structure,composition, and dynamics to emphasize its role as an integral component of forest ecosystems. Because species diversity is highest in the herb layeramong all forest strata, forest biodiversity is largely a function of the herb-layer community. Competitive interactions within the herb layer candetermine the initial success of plants occupying higher strata, including the regeneration of dominant overstory tree species. Furthermore, …

Response Of The Herbaceous Layer Of Forest Ecosystems To Excess Nitrogen Deposition, Frank Gilliam

Frank S. Gilliam

• 1 This review brings into focus what is known about the response of the herbaceous layer of forest ecosystems to increasing nitrogen deposition. The emphasis on forests in general is important for two reasons. First, forests often occupy areas receiving high rates of atmospheric deposition of N. Second, compared with herb-dominated communities, about which much is known regarding response to excess N, forests generally display greater biological and structural complexity. The more specific focus on the herbaceous layer – here defined as all vascular (herbaceous and woody) plants ≤ 1 m in height – is warranted because most of the …

Interspecific Divergence In Foliar Nutrient Dynamics And Stem Growth In A Temperate Forest In Response To Chronic Nitrogen Inputs, Jeffrey May, Sarah Burdette, Frank Gilliam, Mary Adams

Frank S. Gilliam

We studied the effects of excessive nitrogen (N) fertilization on foliar nutrient dynamics and stem growth in three important tree species in a mixed-deciduous forest. Stem diameter growth, foliar N concentrations, nitrogen–phosphorus (N/P) ratios, and nutrient resorption were determined for Acer rubrum L. (ACRU), Liriodendron tulipifera L. (LITU), and Prunus serotina Ehrh. (PRSE) on two 30-year-old watersheds at the Fernow Experimental Forest, West Virginia, USA: WS3, fertilized annually with 35 kg ammonium sulfate ha–1 since 1989, and WS7, an untreated control watershed. In an earlier (1992) study, foliar N concentrations of all three species averaged 11% higher in WS3 than …