Effect of reciprocal transplanting between extremes of plant zones on morphometric plasticity of five plant species in an Oregon salt marsh

Reciprocal transplants of each of five salt marsh plant species were made to determine whether differences in morphology and anatomy between plants at the upper and lower distributional limits of each species were fixed or plastic. At the end of 1 year, Deschampsia cespitosa, Distichlis spicata, Grindelia integrifolia, Jaumea carnosa, and Salicornia virginica all demonstrated morphometric plasticity. Environmental variables were measured to look for correlations between morphological and anatomical changes and environment. Chemical properties of the transplanted soils of D. spicata and of S. virginica became like those of the surrounding soil, while the properties of soil around G. integrifolia and J. carnosa transplants did not change significantly upon being moved. Soil moisture content was always greatest at the lower elevational site and probably accounts for much of the structural change observed in the reciprocal transplants. For example, the increase in the amount of aerenchymatous tissue in S. virginica plants moved to the lower elevational site was most likely caused by the nearly saturated soil at that location.