For years, we knew that the Oregon Department of Geology and Mineral Resources (known as DOGAMI) had LIDAR data for all western Oregon. What is LIDAR you ask. Light Detection and Ranging  (LIDAR) bounces laser light off the earth’s surface to create a detailed image of surface features. And when we say detailed,  we mean VERY DETAILED. Imagine an image so detailed that the diameter of each large tree is revealed!

As you may have guessed, the problem with LIDAR imagery is that the data files are huge. So huge that in 20 years of the CRA working with computer-based mapping and imagery, no one we knew wanted to use LIDAR data.

This year, in stepped Chris Beatty. Chris is spearheading a CRA project to convert LIDAR data (tree height, crown diameter, etc) into forest age classes. This work is super needed since the proposed amendments to the Northwest Forest Plan call for timber cutting in Reserves under 120 years of age.

DOGAMI has a website for viewing their LIDAR data. But the image provided is not all that helpful. Here is an example below:

The first thing Chris did was create a website that reads the DOGAMI tree data and color-ramps trees according to height. Chris named the website Oregon Tall Trees. Here is the link to the Tall Trees webpage. Below is a view of Coast Range forest from Seal Rock to the Heceta Lighthouse from the Tall Trees website. The darkest green areas are the tallest trees. Lighter shades of green signal smaller tree height.

Imagine a map with every large tree identified for all Coast Range forests! That’s a fact of the LIDAR data. Again, you can view your favorite area using the Oregon Tall Trees website. Here’s the web link: Oregon Tall Trees

What about tree age? LIDAR data can not tell the age of a tree. For that, Chris with his colleague Adam, built a special program that merges LIDAR tree height with well known growth tables according to soil fertility. For example, the analysis program will take a 150 foot tall tree and determine that for the tree’s location the tree should be 100 years of age. The analysis program reviews DOGAMI data two acres at a time sampling a set of the tallest trees.

In June, Chris rolled out an initial 100 square mile area of completed analysis. The result is seen in the image below. The area includes parts of Cummins Creek Wilderness in the north, Tenmile valley in the center and Rock Creek Wildernesses in the south.

The final Northwest Forest Plan amendment is to be released this fall. The Forest Service says it will begin implementation in the Spring of 2026. It’s already bad enough that we have to be ready for a potential Forest Service timber attack on Reserve areas. Things could become worse under a Trump administration’s final decision.

Here is the exiting update. Chris reports the core analysis model for is working and stable. Chris and Gavin have focused on increasing productivity to complete an analysis across a huge area. The team made a grid called the “Siuslaw block” which is a rectangle that surrounds the Siuslaw National Forest and adjacent land. It is over 3 million acres. By harnessing multiple
computers with multiple cores and multiple sessions of R on each computer, they have analyzed over a million acres to date!

Chris anticipates completing a first pass of all three million acres of the Siuslaw block before the end of the summer. But much work must be done after the forest age analysis. The analysis must be brought into ArcGIS so that we can build maps usable by local forest defenders. This effort will be a whole second phase of the project.

With enough resources and time, we can take the MARMOT LIDAR analysis north into state forest lands. The state of Oregon is cutting native forests over 80 years of age in the north Coast Range. This is unacceptable. The loss of sequestered carbon alone is reason enough to keep big forests intact. Please consider a donation today so we can push this important work forward. Donate Here.