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Short-term growth responses in individuals of four commercial tree species (Laetia
procera, Simarouba amara, Tapirira guianensis, and Vochysia ferruginea) were
evaluated one and two years after `liberation thinning’ in a young (4.5-year-old), dense
secondary forest stand located in an agricultural settlement in wet, Northeastern Costa
Rica. Liberation thinning involved manual elimination (either by cutting or stem girdling)
of the adjacent `ring’ of competitors in order to release future crop trees (median
diameter: 8 cm DBH), selected on the basis of stem and crown form. The application of
liberation thinning significantly increased diameter growth of future crop trees with
respect to unmanipulated counterparts. Young stands in the region may be attractive
systems for simple silvicultural manipulations due to rapid growth responsiveness,
facilitated by manageable tree size. Detailed observations on stand development and
patterns of crown stratification in coexisting tree species in other dense secondary
stands in the area seems warranted in order to refine silvicultural options aimed at
increasing tree diameter growth.