This study proposes a classification of Argentina's cypress forests into three types: marginal, compact and mixed forests (the latter with Nothofagus spp.). The classification is based on the information from seventy eight plots of cypress forest. Significative differences were found in density, basal areas and tree heights among forest types.
Analysis of the allometric relationship of the trees included in this study shows that: 1) the existing linear relationships between diameter and age are not that close, and 2) height growth is faster in the first years of development than in the later ones. Size distribution of the compact and mixed forest stands show inverted "J". Finally a positive linear relationship was found between stand height and mean annual volume increment. From the latter, it could be concluded that stand height could indicate site quality of cypress forests.