Influence of nutrient availability and tree wildling density on nutrient uptake by Oxalis acetosella and Acer saccharum

Loss of nutrients following pulses of nutrient input in northern hardwood forests and the general effects of atmospheric deposition on forest communities are of concern. Uptake of nutrients by ground layer vegetation, including herbs and tree wildlings, may be important in both of these processes. We brought plants from the field (Catskill Mts, New York) and grew them under controlled environment conditions at two nutrient input levels to determine responses of Oxalis acetosella and Acer saccharum to increased nutrient input and tree wildling density. Oxalis nutrient concentration increased for many nutrients compared to field plants. Both species doubled their P concentration when P input doubled. Biomass of Oxalis was unaffected by both nutrient input level and Acer wildling density. Acer showed a similar response to increased nutrient input and its density did not affect the response of Oxalis to increased nutrient input. Results indicate that both species may be important to nutrient retention in northern hardwood forests. (C) 2001 Elsevier Science B.V. All rights reserved.