New Forests 24: 183–194, 2002.  2002 Kluwer Academic Publishers. Printed in the Netherlands. Mechanical cleaning and prescribed burning for recruiting commercial tree regeneration in a Bolivian dry forest 1 1,2,3, * KIMBERLY HEUBERGER , TODD FREDERICKSEN , MARISOL 1 1 1 TOLEDO , WILLIAM URQUIETA and FREDY RAMIREZ 1 2 BOLFOR, Santa Cruz, Bolivia; The Forest Management Trust, University of Florida, Gainesville, FL, 3 * USA; Current address: TOP BOL 5053, 52-0777, Miami, FL 33152-0777, USA; Author for correspondence (e-mail: nelltodd@bibosi.scz.entelnet.bo) Received 12 March 2001; accepted in revised form 5 February 2002 Key words: Competition, Fire, Logging gaps, Silviculture, Sustainable Forest Management Abstract. A critical component of sustainable forest management is the regeneration of commercially valuable tree species. Mechanical cleaning with machetes and chainsaws, prescribed burning, and a combination of both treatments were applied to recently-created logging gaps in a Bolivian dry forest to evaluate their impact on the natural regeneration of commercial tree species and on control of competing vegetation. The three treatments and an untreated control were applied to logging gaps during the dry season of 1998 and replicated ten times. Eight months following burning, the density of commercial tree regeneration in gaps did not differ statistically among treatments. Relative height growth of total commercial regeneration also did not differ among treatments, although it did vary by species. Reduction in competing vegetation following the application of site preparation treatments was significantly higher, but competing plant cover was beginning to converge among treatments after eight months. Despite better control of competing vegetation, early recruitment and growth responses to burning and cleaning of vegetation in logging gaps do not appear to justify application of these treatments in this forest, especially considering their high costs. Introduction Because a large proportion of Bolivian forests are still intact, management prospects for these forests may be better than many other tropical forests around the world (Fredericksen 2000a). Recently, there has been a growing interest on the part of the Bolivian government and international development groups to preserve forests through conservation efforts and the implementation of sustainable logging prac- tices (Nittler and Nash 1999). However, forest managers are encountering poten- tially conflicting objectives in their attempt to broaden their focus from solely on timber production to include protection and maintenance of biodiversity, and ecological functions (Pinard et al. 1999). Results of ecological and silvicultural research conducted in Bolivia, suggest that these apparent conflicts in the objectives of forest conservation and those of logging can be reconciled (Fredericksen and Putz 2002). However, successful long-term sustainable forest management will be difficult to attain unless regeneration of valuable timber species can be secured (Mostacedo and Fredericksen 1999).