Response of aspen genotypes to browsing damage is not influenced by soil community diversity

Abstract

Both environmental and genetic factors influence plant growth and foliar chemistry. The purpose of this experiment was to investigate the independent and interactive effects of soil community (and soil community diversity), tree genotype, and simulated browsing damage on the growth, biomass allocation and foliar chemistry of Populus tremuloides. We employed a factorial randomized complete block design with four soil treatments of varying diversity, five aspen genotypes, and a simulated ungulate browsing treatment. In the second year of growth, half the trees were subjected to simulated ungulate browsing, and 2 mo later trees were harvested and analyzed for biomass, biomass allocation, and foliar chemistry. Tree genotype was the strongest driver of foliar chemistry, but simulated browsing was the strongest driver of plant growth. Soil community influenced plant growth but not foliar chemistry, and soil community effects were rarely modified by tree genotype or simulated browsing. While environment and genotype had relatively equal influences on plant growth, tree genotype had a stronger influence than environmental effects (soil and simulated browsing) on foliar chemistry. We also documented negative plant–soil feedbacks for tree biomass. Our results highlight future opportunities for research on the potential effects of soil community diversity on trees.