CONTENTS

Articles ROBERTO A. VILLASANA A. and ARLENE SUÁREZ DE GIMÉNEZ Phenological studies of 16 forest species at the IMATACA forest reserve, Bolívar-Venezuela ARMANDO J. BRICEÑO VERGARA Preliminary approach towards an integrated management program for Hypsipyla grandella   (Zeller) in western, Venezuela WILVER CONTRERAS MIRANDA and MARY E. OWEN DE CONTRERAS Building a laminated structural element - Parallam type using Caña Brava wood strips (Gynerium sagittatum) and fenol-formaldehide adhesive WILLIAMS J. LEÓN H. and NARCISANA ESPINOSA DE PERNÍA Crystal inclusions in Cordia thaisiana   Agostini CLIFFORD PEÑA G. and DIXON MORENO P. Evaluation of thirteen cultivars and hybrids of tomato (Lycopersicon esculentum  Mill) in Tocorón, Aragua-Venezuela JAJAIRA OBALLOS Micromorphology of soils in the Capaz basin, Las Cruces - Santa Elena de Arenales region, Mérida-Venezuela JORGE MANRIQUE, GUIDO OCHOA and JAJAIRA OBALLOS Soils in the Santo Domingo basin, Los Frailes sector (Physical-chemical characterization). Mérida-Venezuela JUAN C. VELÁSQUEZ, GUIDO OCHOA and JAJAIRA OBALLOS Soils in the Santo Domingo basin, La Soledad sector (Physical-chemical characterization). Barinas-Venezuela

Essay LUIS E. RODRÍGUEZ P., RAMÓN JAIMES, MIGUEL PLONCZAK and MAURICIO JEREZ Basic considerations about forest management in Venezuela within the frame of sustainable development

Notes BRUNO AÑEZ and HENRY PINO Methods and timing of nitrogen application in Lettuce production LUIS CEDEÑO and CHRYSTIAN CARRERO Cladosporium echinulatum,   causing leaf spots in carnation in Mérida-Venezuela

Thesis EMMERIS IVAN QUINTERO Q. Application of the SWRRB-WQ simulation model in Zarzales - La Grande, Bailadores, Mérida-Venezuela ARNALDO GUEVARA Factibility of Tabebuia rosea   (Bertol D.C.) plantations under de Caparo Method as a silvicultural option in the western lowlands of Venezuela GIOVANNY J. PÉREZ M. Variation of no conventional methods of sampling sediments in suspension. The case of the Boconó river high basin. Venezuela SEIDA R. FINOL R. Validation of the hydrological model SWRRB: water and sediment yield and precipitation in the Guasare basin. Zulia-Venezuela