More information: Valentina Vitali et al, Silver fir and Douglas fir are more tolerant to extreme droughts than Norway spruce in south-western Germany, Global Change Biology (2017). DOI: 10.1111 ...

While Douglas fir and sitka spruce seedlings did fine through the summer heat, western hemlock didn't fare as well by: Amanda Arden Posted: Dec 2, 2021 / 09:00 AM PST ...

Dave Powell/USDA Forest Service (retired) / Bugwood.org. All spruce trees have sharp-pointed needles that are often 4-sided or diamond-shaped in cross-section and have four whitish striped lines.

Flies released to attack hemlock-killing pest Date: June 16, 2015 Source: University of Vermont Summary: A team of scientists has shown that two species of silver flies from the Pacific Northwest ...

The species most impacted included Douglas-fir, western hemlock, western redcedar and Pacific silver fir. “Needles appeared brown or red, and in places branch tips and buds were also killed ...

The amount of forest with problems is up nearly 30,000 acres from 2023 and more than the 10-year average of 519,000 acres, ... the western pine beetle and the silver fir beetle.

The Western hemlock looper moth, a native species that defoliates trees, is common in B.C. but it especially likes to prey on the hemlock, Douglas fir, and red cedar found on the North Shore.

The DNR says this poses a threat to both forest and landscape hemlocks. The balsam woolly adelgid is also an insect and attacks true fir trees. Balsam and Fraser firs in Wisconsin are particularly ...