Impact of fire on the colonization of supports in a native and exotic honeysuckle vine

Restoration of burning to habitats ranging from prairies to oak woodlands is currently being prescribed for much of the eastern US.  One possible outcome of increasing burn frequency is reducing population size of some invasive species.  Lonicera japonica is an exotic species considered a serious pest throughout the southeastern US and numerous studies have attempted to understand the characteristics contributing to the invasiveness of L. japonica while its native congeners are uncommon to rare within the same communities.  Greater plasticity and the capacity to respond to stresses through the rapid deployment of lateral shoots are traits that have emerged as important in contrasts between the invasive L. japonica and its native congener L. sempervirens .  This study examines the impact of fire on the capacity of these two species to find and climb support trellises.   In an experiment examining the capacity of each species to find and climb support trellises, L. japonica  had placed nearly twice as many shoots on trellis supports as L. sempervirens after 7 years of growth.  The experimental plots were burned in early spring 2007.  Most above ground parts of both species were killed, and both species produced new shoots from nodes near at the ground surface.   These shoots recolonized the trellis supports during the spring, and by early summer, there was no significant difference in the number of L. sempervirens  and L. japonica  shoots on support trellises.   The number of L. sempervirens  shoots on trellis supports after the fire was not different than before the fire, while the number of L. japonica  shoots on trellis supports dropped to about half of the pre-fire number.  While neither species is eliminated by fire, this study provides evidence that the competitive imbalance often seen between these two congeners may be more balanced under an increased burn frequency.