Text Box: Do you know what kind of trees you have on your property?  In the mountains of Fremont County many different tree species exist.  Trees common to the area include: Rocky Mountain juniper, limber pine, Douglas-fir, lodgepole pine, Engelmann spruce, sub-alpine fir and aspen.  The following are descriptions and some interesting facts about each of these species.
Rocky Mountain Juniper

This hardy and drought tolerant tree is often described as a shrub due to its bushy appearance.  Most specimens are pyramidal in form, have several stems and do not exceed 20 feet in height.  Rocky Mountain Juniper can be found at lower elevations and is often associated with sagebrush and limber pine.  The leaves are scale-like, pointed, about 1/8 in. long and overlapping in pairs.  The cones resemble a small blue berry and are a prominent food source of many birds.
Limber Pine








This hardy and long-lived tree is common on harsh sites, often growing at high elevations, on rocky and wind-blown sites.  Limber pine has a broad elevational range and can be found at elevations from 5,000-11,000 ft.  The needles are 2-3 in. in length and are clustered in 5 needle bunches near the end of the branches.  The cones are the largest of any conifer in the area, measuring from 3-6 in. in length.  Currently, limber pines in Wyoming are experiencing abnormally high mortality Text Box: rates due to a disease called white pine blister rust.
Douglas-fir
Douglas-fir is considered the tallest tree species in Wyoming.  It can reach heights of 120 ft. on good growing sites.  In the Pacific Northwest, Douglas-fir grows to heights of 300 ft. and is considered the second largest tree in North America.  In Wyoming it is a mid-elevation species that is fairly drought tolerant.  The needles are fairly flat, approximately 1 in. long and fairly soft to the touch.  The cones are 2-5 in. long and have very distinct 3-pronged bracts protruding from beneath the scales.  Currently, many Douglas-fir in the South Pass area are being killed by Douglas-fir beetle.
Sub-alpine fir
Sub-alpine fir is a high elevation species that exists in mixed stands with Engelmann spruce and alone on exposed sites near timberline.  On protected sites, trees attain a maximum height of 100 ft. and develop very narrow, pointed crowns.  Open-grown trees in alpine areas form dense low growing shrub stands that rarely reach heights over 20 feet.  Needles are 1 in. long, rounded and fairly soft to the touch.  The cones grow upright, instead of hanging down and commonly do not fall to the ground but disintegrate on the tree.  Sub-alpine fir is considered a short-lived species due to the many insects and diseases that afflict this tree. 

Text Box: Engelmann spruce
Engelmann spruce is generally considered a high elevation species but is also found on moist sites at lower elevations, such as along the Wind River.  It grows to a maximum height of 100 ft. in Wyoming and is well known for having a very straight trunk.  It is often associated with sub-alpine fir and often forms dense thickets of young, pole-size timber before natural thinning occurs.  The needles are 4-sided, approximately ¾-1in. long and are fairly sharp to the touch.  The cones are 2 in. long, ovoid-oblong and somewhat papery.  Engelmann spruce is a fairly hardy tree and lives to around 400 years.
Aspen








Aspen is the only deciduous tree common to the mountains of Wyoming.  Aspen is the most widely distributed tree of North America.  An aspen stand has one common root system and is therefore, considered one organism.  In fact, the largest living organism in the world is an aspen stand in Colorado.  The “quaking” leaves and white bark make aspen easy to identify.  Aspen stands are excellent wildlife habitat and are home to a wide variety of animal species.  Young aspen and aspen bark are commonly grazed upon by big game species.  Aspen has been on the decline in the western U.S. due to competition by conifers, over grazing by cattle and big game species and the lack of stand replacing events, such as wildfire and timber harvesting.     
by Mark ‘Oly’ Ellison
Wyoming State Forestry Division
Text Box: What Tree Is That?

A variety of trees that are common in the high country of Fremont County