Established in 1872, Yellowstone National
Park is the oldest, largest (in the lower 48 states), and
best-known national park. Its 890,000 hectares sprawl across
broad volcanic plateaus that soar some 2,450 meters above
sea level. Three states, Wyoming, Montana and Idaho, lay
claim to Yellowstone's beauty. Enclosed by the Grand Teton
National Park to the south and a half dozen national forests,
the Yellowstone region shelters a tremendous expanse of
unbroken forest, lush grassland, dramatic mountain ranges,
spectacular valleys, deep lakes, and winding river canyons.
It is a geological wonderland of fossil forests, hot springs,
mud cauldrons, painted pots, and geysers. Its diverse wildlife
community includes bear, elk, bison, coyotes, trumpeter
swans, bald eagles, beaver, trout, and a host of smaller
and microscopic creatures. Small wonder, then, that millions
of people from all over the world visit the park every year.
The visitor services and the science research centers at
Yellowstone are among the best in the world. Yellowstone
National Park is an international treasure. So sensitive
and under such intense scrutiny are the eco-systems of Yellowstone
that if a tree falls in the Yellowstone forest, the odds
are quite good it will be heard not only across the U.S.
but around much of the world.
Lodgepole Pine is King
When you drive through Yellowstone,
you'll pass lovely paintbrush flowers, sand verbena, Rocky
Mountain juniper bushes, fields of grassland, patches of
aspen trees, and several species of spruce and fir trees.
But by far and away the most common tree you'll see, covering
some 80 percent of Yellowstone's forests, is the lodgepole
pine. It grows straight and tall and up to 23 meters high.
In forests where the pines are dense, only the tops of the
trees closest to sunlight have branches, and you get the
sensation you have entered a forest of thousands upon thousands
of telephone poles topped with Christmas trees.
How did the lodgepole pine become so common
in Yellowstone? Curiously enough, the reason has to do with
the periodic wildfires that sweep through these forests.
After a fire strikes, while other tree species must wait
for the right conditions or for some spare seeds to drift
in from a neighboring forest, the eager-beaver lodgepole
is prepared, having on hand two types of cones that are
custom-made for fires. Adult lodgepoles produce both open
cones and serotinous cones.
Open cones shed their seeds in the normal
way when the cones reach maturity. Serotinous cones, on
the other hand, have a resin coating, and they only open
when temperatures are 45º C. or higher, which, in the
relatively cool climate of Yellowstone, happens only in
the heat of a fire. As soon as the ground cools off, lodgepole
seeds from the serotinous cones germinate. The seedlings
spring from the ash-enriched soils. These trees also grow
rapidly, maturing (that is, producing their own dual-type
cones) as early as five years after sprouting.