Antimicrobial Activity of Bark from Four North American Tree Species.

Introduction: Although many backcountry first aid kits contain antibiotic ointment, the supply can be quickly exhausted if a patient has extensive wounds or if there are multiple patients.

Methods: We assessed the antibacterial properties of bark extract from four North American woody plant species known to native Missourians as medicinal plants (, , and ). We tested their antimicrobial properties, with the disc diffusion technique, against four common pathogenic bacterial species: , , , and (now known as )

Results: We report evidence of antibacterial activity of bark extract from all four plant species.

Conclusions: Our results confirm that traditional uses of these species may be useful in fighting infection and could be especially useful in a wilderness setting when modern antibiotics are exhausted.