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North American pines
About 65 species of pines are native to North America. Thirty-six of
them grow in the United States. Botanists divide pines into two groups:
(1) soft pines and (2) hard pines. The trees of these groups differ mainly
in the way their needles grow.
Soft pines, also called white pines, typically produce needles in bundles
of five. Hard pines, also known as yellow pines, ordinarily produce needles
in bundles of two or three. In addition, hard pines generally have heavier,
harder wood than soft pines.
Both hard and soft pines grow naturally in areas throughout North America.
This article divides North American pines into three groups: (1) eastern
pines, (2) southeastern pines, and (3) western pines.
Eastern pines. The eastern white pine is the only soft pine native
to eastern North America. It is common in New England and grows as far
west as Minnesota and as far south as northern Georgia. This huge, majestic
tree may reach a height of over 100 feet (30 meters) and measure more
than 4 feet (1.2 meters) in diameter at its base. It has long, slender
cones and is prized for its white, smooth-grained lumber.
Two important hard pines that grow in Canada and the northeastern part
of the United States are the red pine and the jack pine. The red pine
is found in areas near the Great Lakes, in New England, and in southeastern
Canada. It gets its name from its reddish-brown bark. It has long needles
that grow in bundles of two and is an important timber tree. The jack
pine grows chiefly in sandy soils from the northern Great Lakes region
to northwestern Canada. Its needles grow in bundles of two and it bears
small, curved cones. The cones may remain closed and hold their seeds
for many years. The jack pine is often one of the first trees to grow
after wildfires. The heat of such fires causes the cones to open, releasing
the seeds that produce new trees. The wood of the jack pine is used for
paper pulp.
The pitch pine grows in sandy soils in New England and in shallow soils
in the southern Appalachian Mountains. Its cones are spiny and measure
about 4 inches (10 centimeters) long. Its needles grow in bundles of three.
Southeastern pines. Pines grow throughout the Southeastern United
States. The Virginia pine is found in the southern Appalachian Mountains
and the rolling hills of the Piedmont Region. It has scaly bark, and its
cones measure about 2 inches (5 centimeters) in length. Its needles grow
in bundles of two. The shortleaf pine grows in the same area as the Virginia
pine but is a much taller tree. It may reach a height of over 100 feet
(30 meters). Its bark is divided into irregular plates, and its needles
grow in bundles of two or three. The loblolly pine thrives in many environments
throughout the Southeast. It resembles the shortleaf pine, but its needles
always grow in bundles of three. These three pines all grow rapidly and
are common in abandoned fields and pastures. All are important sources
of lumber.
Many pine species grow in the sandy soils of the Atlantic and Gulf coastal
plains. The longleaf pine grows in particularly sandy soils. It has large
cones and extremely long needles that may reach a length of 18 inches
(46 centimeters). The slash pine grows in somewhat moister soils. Its
needles and cones are smaller than those of the longleaf pine. Both species
are important sources of lumber and resin. The pond pine grows in swampy
areas. It can grow back from its roots after the aboveground part of the
tree has been destroyed by fire.
Western pines. Many species of pines grow in the mountains of
western North America. Different species are found at different elevations.
The Digger pine grows at lower elevations in the Sierra Nevada and in
the Coast Ranges of California. This tree has needles that grow in bundles
of three and cones that may measure as much as 10 inches (25 centimeters)
in length. Digger pine seeds were once an important food for Indians.
A number of important pines grow at slightly higher elevations than the
digger pine. The ponderosa pine is common throughout the Rocky Mountains
and the eastern side of the Cascades, and in the Southwestern United States.
This hard pine grows up to 130 feet (40 meters) tall and produces high-quality
lumber. Its needles grow in bundles of three, and its cones are about
5 inches (13 centimeters) long. The sugar pine and the western white pine
are found at middle elevations in the Sierra Nevada. The sugar pine produces
the longest cones of any North American pine. They may reach nearly 30
inches (76 centimeters) in length. The lodgepole pine grows at higher
elevations than the ponderosa pine in the Sierra Nevada and the Rocky
Mountains. It thrives in sandy soils and its needles grow in bundles of
two. Its small cones may remain closed for years after they mature, and
its seeds are released in wildfires.
The limber pine and the whitebark pine are found in the Rocky Mountains
at some of the highest elevations at which trees can grow. In areas exposed
to strong winds and extreme cold, these two soft pines grow to only about
5 feet (1.5 meters) in height. Elsewhere, they grow 30 to 50 feet (9 to
15 meters) tall. Another soft pine found at extremely high elevations
is the bristlecone pine. Some are among the oldest living things. A number
have lived over 4,000 years.
Several species of pines grow naturally only in small areas of southern
California. For example, the Monterey pine is native to a small area on
the California coast. In this area, its wood has little commercial value.
However, this tree has been introduced into the Southern Hemisphere and
now ranks as a major source of timber in Australia, Chile, New Zealand,
and South Africa.
Other pines
Only a few pine species grow in northern Europe. The Scotch pine, a valuable
timber tree, is probably the most important of these. This pine also is
grown in many areas of North America, where it is widely used as a Christmas
tree.
Many species of pines grow in the countries that border the Mediterranean
Sea. The black pine, also called the Austrian pine, is an important source
of timber in this region. It also is cultivated worldwide as an ornamental
tree. The Aleppo pine is the most widespread pine of the Mediterranean
region. It grows from Spain and northern Africa near the Strait of Gibraltar
to the mountains of Israel and Lebanon.
About 15 pine species grow naturally in southeastern Asia and Japan.
Most of them grow in mountainous areas. In northern Asia, the Siberian
pine ranks as an important pine species. This pine grows from the Ural
Mountains through western and central Siberia to northern Mongolia.
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