This study documents the characteristics of upper montane forests within Cotacachi-Cayapas Ecological Reserve, a protected area in northern Ecuador. On Cotacachi Volcano, there are remnants of forest vegetation extending from about 3650 m down to a crater lake at 3150 m. We examined these forests at four sites located within a deep ravine; the forests were sampled with 50 x 10 m inventory plots placed at 100 m elevation intervals between 3630 and 3330 m. We noted changes in vegetation composition and structure along the altitudinal gradient, as well as variation in these parameters with distance from the forest edge. There were important differences in structure and composition with elevation, but some were unexpected and appear to be related to the influences of past anthropogenic disturbances. For example, the trees at the higher elevations were taller and more massive, suggesting they had not been cut or burned by escaped grassland fires, processes known to have occurred at lower elevations. Little evidence of edge effect was documented within the plots, which is expected if deforestation has converted most of the forest into edge habitat. These patterns may be typical of other remnant forests in the Andes, and provide a basis for understanding the nature of human impact on Andean forests.