Travel Reference
In-Depth Information
PLANTS
Flora from the surrounding mountains, deserts, montane forests, arctic tundra and Great
Plains all converge in Greater Yellowstone, where they are grouped into five distinct veget-
ation zones - riparian, foothills, montane, subalpine and alpine. Yellowstone National
Park's herbarium has inventoried 1717 species, seven percent of which are considered rare.
Trees
Harsher climatic conditions at higher elevations strongly favor hardy conifers. With the ex-
ception of aspen, eight conifers dominate these forests and make up 60% of the region's
total vegetation.
Douglas firs, quaking aspens, shrubs and
berry bushes blanket parts of the landscape from
6000 to 7000ft. Lodgepole pine forests, which
range from 7600 to 8400ft, cover 60% of the
park's broad plateaus. Above 8400ft, Engel-
mann spruce and subalpine fir predominate, in-
terspersed with lodgepoles. Above tree line
(10,000ft), alpine tundra supports lichen, sedges, grasses and delicate wildflowers.
Aspen has radiant silver-white bark and rounded leaves that 'tremble' in the mountain
breezes and turn gold in fall. A regeneration species, aspen tends to reproduce by sending
out root runners rather than by seeding. A stand of aspen is mainly cloned from an original
parent tree.
Not a true fir, Douglas fir is a tall, adaptable and extremely widespread tree that ranges
from the foothills to the subalpine zone and from very dry to quite moist locations. It has
flattened, irregularly arranged needles, 4in-long cones, and thick, corky bark that protects it
from fire.
True firs resemble spruces, but have flat, blunt needles and cones pointing upward on
upper branches. The most widespread is subalpine fir with silvery-gray bark bearing hori-
zontal blister scars.
Many lodgepole pines are dependent on periodic forest fires to melt the resins that seal
their cones shut, ensuring seed dispersal after fire has prepared a fertile bed of ash. Lodge-
poles sport needles in bunches of two and straight, narrow 'polelike' trunks that make for
dense stands in recently regenerated forests.
For a leg up on spotting wildlife carry a field guide
such as
Watching Yellowstone & Grand Teton
Wildlife
by Todd Wilkinson.
