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The invasion of jumping worms, a small group of pheretimoid earthworm species from Asia, has increasingly become an ecological, environmental and conservation issue in forest ecosystems and urban-suburban landscapes around the world. Their presence is often noticed due to their high abundance, distinctive “jumping” behavior, and prominent granular casts on the soil surface. Although they are known to affect soil carbon dynamics and nutrient availability, no single paper has summarized their profound impacts on soil biodiversity, plant community, and animals of all trophic groups that rely on soil and the leaf litter layer for habitat, food, and shelter. In this study, we summarize the biology, invasion, and ecological impacts of invasive jumping worms across North America. We highlight potential impacts of this second wave of earthworm invasion, contrast them with the preceding European earthworm invasion in temperate forests in North America, and identify annual life cycle, reproductive and cocoon survival strategies, casting behavior and co-invasion dynamics as the key factors that contribute to their successful invasion and distinct ecological impacts. We then suggest potential management and control strategies for practitioners and policy makers, underscore the importance of coordinated community science projects in tracking the spread, and identify knowledge gaps that need to be addressed to understand and control the invasion.

The magnitude of the change in tree growth caused by climate warming can be highly dependent on biological context, including factors such as the presence of associated decomposers and their behaviors. We test the hypothesis that 1) the presence of earthworms modifies the response of soil inorganic N and tree growth to warming via the change of cast production; and furthermore 2) the type of soil as food for earthworm differentiate the earthworm response and its effects on the plant-soil system. We conducted a microcosm experiment rearing a geophageous earthworm species (Aporrectodea rosea) and birch (Betula ermanii) seedlings with two types of soil (sedimentary soil and serpentine soil) under two temperature regimes (ambient and ambient +3.3 °C). While the warming increased the cast production by the earthworms in the serpentine soil, it did not influence cast production in the sedimentary soil. The net nitrogen mineralization rate and the net inorganic N production showed similar dynamics to cast production under the warmer conditions, although the net nitrification rate did not. A significant increase in tree height from warming was observed only in the serpentine soil with earthworms, and the tree height was positively correlated with inorganic N production. The context-dependent change of soil N dynamics to warming could be caused by differential feeding activity of earthworm, and it results in the modification of the growth characteristics of birch seedlings.