This dataset consists of three zip archives containing valuable visual and measurement data related to tree assessments conducted using the Apple Vision Pro (AVP) technology. The first zip archive, images.zip, includes images taken in the forest, presented in .PNG and .JPG formats. These images capture various aspects of the study area and the measurement process. The second archive, videos_app_HR.zip, features videos recorded with the AVP using the "Handsruler" app, which focuses on measuring diameter at breast height (dbh) at 22 designated sample plots. Each video file is labeled with a numeric identifier that corresponds to the specific sample plot number, allowing for easy reference and organization. The third archive, videos_app_TM.zip, contains videos from the "Tape Measure" app, documenting dbh measurements taken at 17 sample plots. Similar to the previous videos, the file names indicate the respective sample plot numbers. In addition to the visual data, the dataset includes a comma-separated values (CSV) file named information_all_trees.csv, which consolidates all reference data regarding individual trees and sample plots. Each row in this file represents a single tree and includes several columns, each providing specific details about the measurements and observations. The column headers in information_all_trees.csv are as follows: PLOT_ID: The numeric identifier for each sample plot. tree_species_short: Abbreviation of the tree species. caliper_dbh: The manually measured dbh of the tree in centimeters. AVP_App1_dbh: The dbh measurement obtained from the AVP app "Handsruler" in centimeters. AVP_App2_dbh: The dbh measurement obtained from the AVP app "Tape Measure" in centimeters. res_App1: The difference between the dbh measured by the "Handsruler" app (AVP_App1_dbh) and the manual measurement (caliper_dbh), expressed in centimeters. res_App2: The difference between the dbh measured by the "Tape Measure" app (AVP_App2_dbh) and the manual measurement (caliper_dbh), expressed in centimeters. tree_species: The Latin name of the tree species, with genus and species connected by an "_". tree_class: Classification of the tree into a species-specific category. date: The date of the recordings. time_App_1_min: The duration of all dbh measurements at the entire sample plot using the "Handsruler" app, in minutes. time_App_2_min: The duration of all dbh measurements at the entire sample plot using the "Tape Measure" app, in minutes. time_manual_caliper_min: The duration of all dbh measurements at the entire sample plot conducted manually, in minutes. measuring_person: The individual field worker for conducting all dbh measurements (manual and both AVP apps) at the sample plot. mean_slope_degrees: The average slope of the terrain across the sample plot, expressed in degrees. This comprehensive dataset provides essential insights into the effectiveness of the AVP technology for measuring tree dimensions and contributes to ongoing research in forest management and ecological studies. The included videos and images serve as a visual reference for the measurement processes, while the CSV file encapsulates the quantitative data necessary for analysis. Each row in the CSV file represents a single tree, facilitating detailed examinations of individual measurements and comparisons across different sample plots.