Vegetation

Harvested Area

The first timber harvest at the Andrews Forest occurred in 1951 to study the effects of logging on hydrology, sediment yield, and nutrient losses. Later harvests were done to test different harvesting techniques. Learn more about the history of the Forest on our History page.

First Harvest

The first timber harvest at the Andrews Forest occurred in 1951. Scientists initiated three sets of experimental watersheds designed to study the effects of logging on hydrology, sediment yield, and nutrient losses. Treatments included clearcutting and partial cutting, and one watershed was left in its “natural” forested condition as a control. Learn more about the history of the Forest on our History page.

Plants

Plant species at the Andrews Forest include enormous Douglas fir trees, which can reach 300 feet tall, and the tiniest mosses. The 505 species recorded include plants with flowers, cones, catkins, and fruits. The full list of plants species can be found on our Species Lists page. 

Carbon stored reflects timber harvest history

The amount of carbon stored in tree trunks, branches, leaves and other biomass — what scientists call “aboveground live carbon” — is determined more by timber harvesting than by any other environmental factor in the forests of the Pacific Northwest, according to a report published by researchers at Oregon State University: "Complex mountain terrain and disturbance history drive variation in forest aboveground live carbon density in the western Oregon Cascades, USA" (doi:10.1016/j.foreco.2016.01.036).

Tallest Tree

The tallest tree on the Andrews Forest, a Douglas Fir, was identified by LIDAR imaging.  If you saw the previous version of this Fast Fact, you would have seen that the tallest tree on site was 299 feet, measured in 2008. The height of that tree was verified in 2009 with a measuring tape! This other, now taller tree, was measured by LIDAR in 2016. A cross-section of that LIDAR image is pictured here. As a point of comparison, the Statue of Liberty stands at 305 feet tall, including her base. 

old-growth trees area

Most of the Andrews Forest is covered in dense forest. Huge, iconic Pacific Northwest old-growth conifer forests grow here with cedar, hemlock, and moss-draped ancient Douglas fir trees. See our Forest Description page for more information.

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