Replication data for: The effect of reforestation on bird communities in two types of forests in the Nevado de Toluca, Mexico.

Numbers of individuals and volumes of the plant species from the three strata (herbaceous, shrub, trees), for the native forest (natural forest; Amanalco) and reforested forest (Cacalomacan), as well as the corrresponding Importance Value Index (IVI). The vegetation attributes were measured in February and March 2016 within a 20 x 12 m rectangle. Inside each rectangle, a mist net was the symmetry axis (dividing the rectangle in two). We counted all the trees from each species inside the rectangle and measured the diameters of all the trees at breast high (DBH) to the nearest 0.5 cm in small trees, and to the nearest 1.0 cm in large trees. We estimated the volume of each tree at DBH, and both the density of all the tree species. To estimate the attributes of shrub and herbaceous strata, we traced 20-meter-long perpendicular lines at the limits and at the midpoint of the net, being the net the midpoint of these lines. We estimated the volumes of the shrubs crossed by these lines. When it was possible to distinguish an individual shrub, we approximated its volume as the volume of a cylinder. When the shoots of different individuals were indistinguishable (“shrub wall”), we approximated their pooled volume as the volume of a cuboid and counted the number of shoots. The volume of the herbaceous stratus was estimated in a similar manner (Fig. 2). The determination of the volume of the species refers to occupation and was read from the regular cylinder formula (w × l × h), where: w – width, l – length and h – height. The total volume of each species was estimated as follows: 1. When it was possible to distinguish between individuals of the same species, the total volume was obtained by adding the volumes of the stems of each plant. 2. When it was not possible to distinguish between individuals of the same species, the total volume was measured as all the individuals as one. A different group of individuals was considered if there was a distance equal to or greater than 50 cm between two neighboring groups. For each rectangle, dominance was obtained by dividing the total volume of each species by the total volume of all the species. Density was obtained by dividing the number of individuals of each species among the total number of individuals of all the species in the stratum. The importance value index (IVI) was obtained by summing the dominance and the density. The same indices were calculated for shrubs and herbaceous.