The growing interest in medicinal plants from both international industry and local markets
requires management of tree bark harvesting from natural forests in order to prevent inappropriate
exploitation of target species. This study was designed to determine the bark re-growth response of
a selected number of medicinal tree species as a basis for the development of an optimal bark
In 2004, bark was harvested from 925 trees belonging to 12 species in 38 sites in a dry forest in
Benin, West Africa. Two years later, the response of trees to bark harvesting was examined with
respect to re-growth (edge or sheet), development of vegetative growth around the wound, and the
sensitivity of the wound to insect attack.
, showed complete wound recovery by
edge growth. At the other extreme,
very poor edge growth.
showed good sheet growth, whereas the other 11 species had
none or poor sheet growth after total bark harvesting. In contrast, partial bark removal allowed
better sheet growth in all 12 species studied.
Insect sensitivity was species-specific. Insect attacks were negatively correlated with nonrecovered
wound area, but there was a marked species effect for the same rate of regeneration.
had very good and similar re-growth, but
susceptible to insect attack, whereas
appeared to be very resistant. Only a few individuals
developed vegetative growth, and each tree usually developed only one or two agony shoots,
but there was no significant difference between species.
Synthesis and applications
. This is the first study to provide data on the ability of trees to close
wounds after bark harvesting in West Africa. We report large variability in the response of different
species to our bark harvesting technique, and identify just two out of the 12 study species as suitable
for sustainable bark harvesting. Based on our results, we developed a decisional step method to help
forest managers select the best techniques for managing medicinal tree species as an alternative to
bark harvesting, for example, coppice management, harvesting leaves instead of bark, stand establishment,
and collaboration with timber companies.
||bark, medicinal trees, re-growth, West Africa, insect attack, vegetative growth, wound, sustainable harvesting, forest management