LAST CALL for private woodland owners to help expand forest inventory. Deadline to apply is midnight June 30, 2025.
Woodland owners with greater than two acres are eligible to participate in a new effort to expand forest inventory. Sign up today.
Forest inventory provides data on the species and volume of trees in the woods, and can offer insight to the health of forests and how they’re changing. This information can be used by land managers to:
- Learn about fire fuel loads and how to reduce wildfire risk
- Improve forest management relating to harvest planning, wildlife habitat, tree planting or trail development
- Create forest stewardship plans to sustain healthy, resilient and beautiful forests for generations to come
To gather this information, the DNR Resource Assessment Program collects remotely sensed data using light detection and ranging lidar-based technology, combined with field data called plot-based inventory (PBI), to create precise forest inventory information across Minnesota’s ever-changing forest landscape.
Until now, PBI has been conducted primarily on public lands, but nearly half of Minnesota’s woodlands are privately owned. Private woodlands are needed to increase the precision and accuracy of these new forest inventory models and maps to get a more complete picture of all of Minnesota's forests. More thorough data will provide land managers of all ownership types with better information to help ensure the continued benefits of Minnesota’s forests.
Types of forest inventory
Lidar based inventory
Airborne lidar (light detection and ranging) uses laser pulses sent from an aircraft to create 3D information of the earth’s surface, capturing natural and built features on the landscape. The lidar-derived information combined with the PBI data is used to create mathematical models that are applied across the entire landscape. Watch the Lidar applications for Plot Based Forest Inventory (PBI) at MNDNR video to help understand how DNR uses remotely sensed data to support PBI.
Plot Based Inventory (PBI)
Professional foresters collect plot-based inventory (PBI) data by visiting thousands of one-tenth-acre field plots across Minnesota. Tree measurements within the plot area are collected, including a precise location of the plot. Watch the PBI Data Collection Tutorial video for a look at how foresters gather this type of data.
Stand level inventory
Forest stand boundaries are polygons drawn in a Geographic Information System (GIS) by foresters based on a variety of parameters, including but not limited to forest classification, areas with similar site conditions, and current, past, or future management objectives. The forest condition and structural characteristics for each stand are summarized for the entire polygon in a forest inventory. The DNR manages their forest inventory in a dataset accessible for download on the Minnesota Geospatial Commons website. This dataset uses stand level polygons and only includes lands administered or managed by the DNR.
Other resources
To find out more about our other services, visit the DNR Resource Assessment Program website or email Resource Assessment.