Data from: Common alien plants are more competitive than rare natives but not than common natives

Success of alien plants is often attributed to high competitive ability.
However, not all aliens become dominant, and not all natives are
vulnerable to competitive exclusion. Here, we quantified competitive
outcomes and its determinants, using response-surface experiments, in 48
pairs of native and naturalized alien annuals that are common or rare in
Germany. Overall, aliens were not more competitive than natives. However,
common aliens (invasive) were, despite strong limitation by intraspecific
competition, more competitive than rare natives. This is because alien
species had higher intrinsic growth rates than natives, and common species
had higher intrinsic growth rates than rare ones. Strength of
Interspecific competition was not related to status or commonness. Our
work highlights the importance of including commonness in understanding
invasion success. It suggests that variation among species in intrinsic
growth rates is more important in competitive outcomes than inter- or
intraspecific competition, and thus contributes to invasion success and
rarity.