The natural forests of the Agua de la Virgen area are sub-Andean forests described as hygrophytic or subhygrophytic and equivalent to the montane and submontane ombrophilic tropical forest of the UNESCO classification (1973) and the humid, very humid and pluvial forests of the premontane and low montane from Holdridge (1967). They correspond to premontane, primary and secondary cloud forests, where the frequency of the fogs tends to raise the ambient humidity and decrease evapotranspiration.

The Reserve is made up of conserved secondary forests in an advanced state of growth, with a canopy that reaches 15 m in height and some trees reaching up to 20 meters, as is the case of Barbatuscos (Erythrina sp.), Guamos (Inga sp. .) and Sloanea sp. In general, the forests are dominated by a bamboo called locally “reed” (Rhipidocladum racemiflorum), which is the preferred feeding site for the Recurve-billed Bushbird. The most characteristic families observed in the understory are Bromeliaceae and Rubiaceae.