In 1988, the 12 treatments consisted of 11 tree species, and one 'control', in which regeneration would occur naturally. Trees in the surrounding plots soon overtopped the 'control', so it did not prove valuable. Two exotic species have been removed to prevent their spread, and three species have either died or did not establish well.
As of 2003, six of the 11 originally planted species had survived in all four blocks, and formed closed canopies. These six species differ in traits such as N-fixation, rooting depth, and growth rates. The following table is based on Fisher (1995), Haggar et al. (1997), and our 2003 measurements :
| Species | Family | Traits | Mean tree size (age 15 y) | |
| dbh (cm) | height (m) | |||
| Hyeronima alchorneoides | Euphorbiaceae | heavy litter | 22.0 | 21.4 |
| Pentaclethra macroloba | Fabaceae | N fixer | 15.8 | 8.5 |
| Pinus patula (exotic) | Pinaceae | deep roots | 28.6 | 22.0 |
| Virola koschnyi | Myristicaceae | deep roots | 21.4 | 18.0 |
| Vochysia ferruginea | Vochysiaceae | 34.2 | 25.5 | |
| Vochysia guatemalensis | Vochysiaceae | deep roots | 28.4 | 22.3 |
Literature cited
Fisher, R.F. 1995. Amelioration of degraded rain forest soils by plantations of native trees. Soil Sci. Soc. Am. J. 59:544-549.
Haggar, J. P., K. Wightman and R. F. Fisher. 1997. The potential of plantations to foster woody regeneration within a deforested landscape in lowland Costa Rica. For. Ecol. Managem. 99: 55-64.
References for the tree species descriptions (pdf attachments) :
Dvorak, W.S. 2002. Pinus tecunumanii Eguiluz & J.P. Perry. IN: Vozzo, J. A. (ed.). Tropical Tree Seed Manual. Agricultural Handbook 721. Washington: Forest Service, United States Department of Agriculture. p. 514-517.
Flores, E.M. 2002. Hyeronima alchorneoides Allemao IN: Vozzo, J. A. (ed.). Tropical Tree Seed Manual. Agricultural Handbook 721. Washington: Forest Service, United States Department of Agriculture. p. 514-517.
Flores, E.M. 2002. Pentaclethra macroloba (Willd.) Kuntze. IN: Vozzo, J. A. (ed.). Tropical Tree Seed Manual. Agricultural Handbook 721. Washington: Forest Service, United States Department of Agriculture. p. 601-604.
Flores, E.M. 2002. Virola koschnyi Warb. IN: Vozzo, J. A. (ed.). Tropical Tree Seed Manual. Agricultural Handbook 721. Washington: Forest Service, United States Department of Agriculture. p. 772-774.
Fournier, L.A. 2002. Vochysia guatemalensis Donn. Sm. IN: Vozzo, J. A. (ed.). Tropical Tree Seed Manual. Agricultural Handbook 721. Washington: Forest Service, United States Department of Agriculture. p. 778-780.
Rodríguez Sánchez, L. and E. Müller. 2002. Vochysia ferruginea Mart. IN: Vozzo, J. A. (ed.). Tropical Tree Seed Manual. Agricultural Handbook 721. Washington: Forest Service, United States Department of Agriculture. p. 775-777.
Additional References
Flores, E.M. 2002 IN: Vozzo, J. A. (ed.). Tropical Tree Seed Manual. Agricultural Handbook 721. Washington: Forest Service, United States Department of Agriculture. p. 514-517.
Flores, E.M. 2002. Chapter I. Seed biology. IN: Vozzo, J. A. (ed.). Tropical Tree Seed Manual. Agricultural Handbook 721. Washington: Forest Service, United States Department of Agriculture. p. 13-118.
Flores, E. M. 2004 Tree Seed Physiology. IN: Burley, J., Evans, J. & Youngquist, J. (eds.). Encyclopedia of Forest Sciences. Oxford, UK: Elsevier Ltd. P 1590-1600.
Flores, E.M; Obando, G. 2003 Arboles del trópico Húmedo. Valorsocioeconómico. Cartago, Costa Rica: Editorial Tecnológica de Costa Rica. 922 p. (There is a related data base in www.fundecor.org ).
