A Call for Enhanced Forest Inventory Practices to Protect Old Growth Ecosystems

We face a struggle in our work to protect the old growth pine forests in Ontario due to the limitations of the Ministry of Natural Resources’ (MNR) Forest Resource Inventory (FRI). While the FRI is useful for commercial timber planning, it falls short in identifying the location and extent of old growth forests.

The FRI provides a map of the landscape identifying the various stands of trees, their dominant species composition, and an estimate of their age (therefore size). The FRI categorizes all stands of trees older than 125 years into a single group. While this may be practical for foresters focused on commercial viability, it does not serve the interests of environmentalists who need detailed information about the age and characteristics of these stands. For instance, knowing whether a stand consists of trees that are 150, 250, or even 350 years old is crucial for effective conservation efforts.

Historically, the FRI was developed through meticulous manual mapping, but as we know, this system has become outdated. Attempts to modernize the FRI in the 2000s using satellite imagery, referred to as the eFRI, did not yield satisfactory results. During the recent Temagami Forest management planning process, environmental experts found little correlation between the eFRI data and the actual locations of known old growth stands. This discrepancy highlighted the inadequacy of the eFRI in detecting and mapping old growth pines, ultimately hindering our ability to protect these vital ecosystems.

However, there is hope on the horizon. The MNR is now experimenting with LiDAR (Light Detection and Ranging) technology, which promises to provide high-resolution data on forest structure and species composition. This advancement could significantly enhance our understanding of forest ecosystems and aid in the identification of old growth characteristics.

To ensure the success of this new initiative, we urge the MNR to incorporate two essential elements into the LiDAR-derived FRI. First, it is imperative that the inventory distinguishes between various age classes of older trees, rather than lumping all stands over 125 years into one category. A comprehensive inventory should clearly identify the locations of 200-year-old and 300-year-old stands, as the ecological significance of these trees varies greatly.

Second, we advocate for the new LiDAR data to be validated against known stands of old growth structure. Ground-truthing the data in collaboration with experienced observers in parks and conservation reserves will enhance the accuracy of the inventory and build public trust in the MNR's assessments.

By incorporating these two critical components, we can reduce conflicts in future forest management planning processes and provide Ontarians—and the world—with a true and complete picture of our rich forest heritage. It is our collective responsibility to safeguard these irreplaceable ecosystems for future generations.

Gord Miller, Chair of the Board - Earthroots

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