Forest cover measurements were collected at 1246 native forest sites that form part of a network of permanent 20 x 20 m plots spread throughout New Zealand. A total of 1831 plant species were present in these plots, with the most common being herbs, graminoids, ferns, shrubs and trees. Plant cover (in ordinal categories) was assessed for each species in several tiers at different heights. The cover data we analysed (NZ_native_forest_cover.csv) were the maximum cover recorded over all the tiers at the 964 sites identified as native forests, containing 1311 species with at least one presence. NZ_native_forest_species.csv contains species data including species name, exotic/native, and plant type (tree, shrub, etc.), corresponding to the plant species in the columns of NZ_native_forest_cover.csv. We acknowledge the use of data drawn from the Natural Forest plot data collected between January 2002 and March 2007 by the LUCAS programme for the Ministry for the Environment, New Zealand.