Effects of Liming on Oxalis acetosella and Lycopodium lucidulum in a Northern Hardwood Forest

Abstract

1. Laboratory and field experiments were undertaken to determine the responses of Oxalis acetosella and Lycopodium lucidulum to the application of 'lime' (a mixture containing 96 or 98% CaCO3). In a growth chamber experiment, lime was incorporated into trays at rates of 1.5 and 4 5 kg m2. In a field experiment, lime was broadcast on nine 10_0-m2 plots in a deciduous forest and a wooded wetland at rates of 05, 1.0 and 15 kgm-2. Response of plants was assessed in limed (broadcast and incorporated) and non-limed treatments by measuring their growth and tissue nutrient concentrations. Following these experiments, two subcatchments (1 0 kM2) of the Woods Lake catchment basin, within the Adirondack Park, were treated with 1O 0kg m-2 of lime by helicopter. Plants were harvested and nutrients analysed. 2. In the growth chamber experiment, Oxalis acetosella responded to the 1'5 kg m-2 lime treatment with increased leaf biomass and area. Stem elongation of L. lucidulum decreased with liming. 3. In the growth chamber experiment, in limed trays, concentrations of Ca in aboveand below-ground tissue of 0. acetosella, and also in older-than-current stems, rhizomes and roots of L. lucidulum, were all higher than controls, whilst Mg was lower in 0. acetosella leaves. In field experiments, limed plots were found to contain higher concentrations of Ca than controls in the leaves of 0. acetosella and the older stems of L. lucidulum. In both experiments, K concentrations were lower than controls in leaves of 0. acetosella, but were higher in older stems of L. lucidulum from the limed field plots. 4. Calcium concentrations were higher than controls in 0. acetellosa and L. lucidulum above-ground tissues from limed subcatchments; K concentrations were lower in 0. acetosella leaves but higher in L. lucidulum older-than-current stems. In contrast to the growth chamber experimental findings, N concentrations were lower than controls in 0. acetosella leaves from limed subcatchments.