Species distributions are changing across the world due to climate change, affecting biodiversity and ecosystem services. Wide variation in the directionality of these distributional shifts suggests that more complex interactions beyond warming temperatures are influential. The role of interactions between the abiotic and biotic environment, which may provide insight into the unexplained variation in distribution shifts, remains largely unexplored. We aim to test the relative importance of abiotic, biotic, and abiotic-biotic interactions for range shifts by manipulating soil moisture concurrently with competition and herbivory in seedlings of three eastern US temperate tree species: Acer rubrum, Liriodendron tulipifera, and Liquidambar styraciflua.