We compared growth and herbivory in an introduced, invasive vine Lonicera japonica (Caprifoliaceae), and its native congener L.  sempervirens in a deciduous forest in central Mississippi. Twenty pairs of congeners were matched for proximity (< 3m apart) and initial size. L. japonica grew more rapidly than L sempervirens in length, leaf area, and in the number and length of branches. The incidence of herbivory was similar for the two species in the first year of our study. During the second year, which was drier in late summer than the first, L. sempervirens not only suffered more damage from herbivores but also abscised damaged leaves, resulting in a substantial loss of leaf area in late summer. By contrast, L. japonica retained even severely damaged leaves and continued to increase in leaf area throughout the summer. Since L. japonica suffered less damage from herbivores than its native congener in one of the two years for which we have data, release from enemies may account in part for its success as an invader. However, L. japonica also appeared to respond differently to the combined stress of drought and herbivory, retaining even heavily damaged leaves. The ability to produce and maintain a large leaf area despite herbivory and adverse growing conditions may also contribute to the success of L japonica as an invader. Our results, obtained by measuring unmanipulated paired congeners in the wild, are in accord with the results of previous studies of these two species in experimental plantings.