tree identification

Asked October 4, 2020, 3:14 PM EDT

I'm curious about two kinds of trees whose branches grow noticeably downward from the trunk. I've seen many of these trees at elevations around and above 5200 feet, near Tumalo Falls and on trails leading upward from the Cascade Lakes Highway. Tree 1 (see photos) has short needles and thick, dark bark with vertical ridges. Tree 2 has longer needles and thin-looking, lighter bark with horizontal and vertical lines. I also noticed a Tree 2 heavily infested with what looks like mistletoe (see poorly focused photo). My questions: What kind of trees are these? Is the propensity for branches growing downward from the trunk peculiar to these kinds of trees, or common among evergreens? Is this Western dwarf mistletoe (which I've seen on Ponderosa pines), or another mistletoe? Thanks! --Jeff McGuire (more photos to come)

Deschutes County Oregon

1 Response

Hi, those are lodgepole pine (Pinus contorta) and Mt. Hemlock (Tsuga mertensiana).

Yes, indeed, the lodgepole pine has dwarf mistletoe infections (Arceuthobium americanum). This is a different species from western dwarf mistletoe (A. campylopodum) on ponderosa pine. But is very common on lodgepole pine.

High elevation snow loads may be responsible for the downward branches, as the snow can be very heavy and wet at times. These high elevation trees tend to be pliable. Mt. Hemlock can have very downward sloping branches, and this may also be due to maximizing foliage exposure to sunlight. (hypthesis)