Combining biogeographic approaches to advance invasion ecology and methodology

1) Understanding the causes of plant invasions requires that parallel field studies are conducted in the native and introduced ranges to elucidate how biogeographic shifts alter the individual performance, population success, and community-level impacts of invading plants. Three primary methods deployed in in situ biogeographic studies are directed surveys, where researchers seek out populations of target species, randomized surveys, and field experiments. Despite the importance of these approaches for advancing biogeographic research, their relative merits have not been evaluated.
2) We concurrently deployed directed surveys, randomized surveys, and in situ field experiments for studying six grassland plant species in the native and introduced ranges. Metrics included plant size, fecundity, recruitment, abundance, and invader impact, as well as soil properties and root associations with putative fungal mutualists and pathogens.
3) Consistent with key invasion hypotheses, Bromus tectoru...