Tree crowns of the north-west corner of the permanent sample area in the Kaluzhskiye Zaseki Nature Reserve

The studies were conducted in the Kaluga Zaseki Nature Reserve on a permanent sample plot (PSP) established in an old-growth broadleaved forest. The stand on the PSP has a complex structure, consisting of several tiers. There are 6 species of broad-leaved trees in the stand: oak (Quercus robur), ash (Fraxinus excelsior), elm (Ulmus glabra), sharp-leaved maple (Acer platanoides), field maple (A. campestre), linden (Tilia cordata) and 2 small-leaved trees - birch (Betula spp.) and aspen (Populus tremula). The oldest oak trees are about 300 years old. The size of the PPP is 440 × 200 m, this work was done on a 40 × 40 m plot located in the northwest corner of the PSP. For tree detection, orthophotomaps were used based on aerial photography materials taken with a DJI Phantom IV Pro quadcopter. Photogrammetric processing was carried out in Agisoft Metashape software (version 1.6.1.10009). The data set contains two fragments of multi-season orthophotos in tif format and corresponding files in shp., dbh. and shx. formats, which contain information on crown boundaries and species of marked trees.