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

One of the struggles that Earthroots has had when dealing with the information base of the MNR about old growth pine forests is to locate and define the extent and location of these ecosystems so we can work on protecting them. MNR uses a database called the Forest Resource Inventory (FRI) to inform all it’s planning and management. The FRI provides the ministry with a map of the landscape identifying the various stands of trees, their dominant species composition and an estimate of their age (therefore size). The use of this information’s to plan the harvest and extraction of commercial timber. It is not particularly useful in identifying old growth and especially very old growth. The historic mapping lumps all stands where the trees are older than 125 years into one category. This practical to the foresters who consider such stands to be noncommercial but it is not useful to environmentalists who would like to know if stands were distinguished by trees 150, 250 or 350 years old.

The FRI is and old system. The original mapping was done by humans who laboured for hours working with optical stereoscopes over areal photographs. It was highly skilled work but keeping this system updated in these times isn’t practical or economical. In the 2000s MNR attempted to improve the FRI using satellite imagery and computer interpretation. This technique produced a mapping data base that some people called the eFRI. Unfortunately, in the last Temagami forest management planning process, when Earthroots and other environmental experts with field experience tried to match the eFRI data to ground locations withstands of known old growth characteristics there was little or no correspondence. It was evident that the eFRI was not detecting and mapping old growth pines. The resulting Temagami Forest Management Plan could not be used to protect old growth.

But now there is a new development! MNR is now experimenting with the use of LiDAR to remotely measure the stand structural characteristics and species composition of the forest landscape. LiDAR or Light Detection And Ranging is a system in which light is emitted from a fast firing laser.This light travels to the surface and reflects off the ground and also tree branches and bounces back to the sensors on the plane. From the received information the forest structure is revealed (LiDAR is not new technology but its used in forest analysis is recent).

So hopefully we will soon get the kind of high resolution forest inventory information we need. But, there are two things we have asked MNR to include in any future LiDAR derived FRI which are essential. We need for the new FRI to include various stands of older age class trees, not just everything over 125years in one lump. A true and complete forest resource inventory would include the distinct location of 200 year old stands and 300 year old stands.There is an important difference in these older ranches.

And, in addition, we need for the new LiDAR data to be ground truthed against known stands of old growth structure. Perhaps those in some of the parks and conservation reserves where there is data and various human observers are familiar with the forest. As stewards of all the resource riches of the public forest the people have to be confident that our inventories are correctly identifying all the old growth features.

 These are the two things we need to encourage and entice MNR to include in the newLiDAR scanning program. Their inclusion will reduce the conflict with the public in future forest management planning processes and provide the citizens of Ontario and rest of the world with a true and complete picture of our rich forest  heritage.

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