A tree is generally defined as a woody plant having one well-defined
stem and a more or less definitely formed crown, usually attaining a
height of at least eight feet. Using water and minerals from the soil,
gases from the air and energy from the sun, a tree manufactures the food
it needs for growth and reproduction. Trees, like man, grow rapidly when
they are young but gradually their growth decreases; they begin to
deteriorate and eventually die. Nature then reduces them to the elements
from which they were derived.
The terms “hardwood,” “softwood,” “deciduous” and “non-deciduous” are
often encountered in tree literature. These terms are confusing and
often misleading. Needle-bearing or cone-bearing trees are designated as
softwoods even though the wood may be dense. Hardwoods are the
broad-leaved (unlike needles or scales) trees, the wood of which may be
dense or soft.
The conifers, or softwoods, generally retain their leaves more than one
growing season and produce seed in cones; however, there are exceptions.
Baldcypress, a conifer, is deciduous since it sheds its leaves in
autumn. Cedar and juniper produce berry-like cones that scarcely
resemble cones.
The hardwoods, or broad-leaved trees, are generally deciduous; i.e.,
they shed their leaves in autumn. Texas has many exceptions, for
example: southern magnolia, live oak and American holly which retain
green leaves through the winter.
More than half of the 1,100 species of native trees in the United States
are found in the South. Of these, more than 200 species and varieties
are native to Texas. In addition, many exotic species have been
introduced and now grow in many parts of the state.
The four main forest regions of Texas include: the Southern pine forest
in East Texas; the central hardwoods, the post oak and cross timbers of
North-central Texas; the semi-tropical forest in the Rio Grande Valley
region of Texas; and the mountain forest, the timbered areas of West
Texas which are a continuation of the timber types of the Southern Rocky
Mountains. In Texas, trees are the principal vegetative cover on an
estimated area of 28,805,617 acres.
[Illustration: TREE REGIONS]
PINE-HARDWOOD
CEDAR BREAKS
POST OAK
WEST CROSS TIMBERS
EAST CROSS TIMBERS
MOUNTAIN FORESTS
Texas also has minor tree areas which are almost restricted to Texas;
the cedar breaks and the oak shinneries. Some of the shinnery trees are
among the smallest in America. In places, fully matured trees are not
over knee-high and resemble pigmy forests. In other areas, the same
species grows 20 to 30 feet tall to form almost impenetrable thickets.
The pine-hardwood forests of East Texas, comprise 12,525,417 acres in
all or part of 42 counties. Lumber, paper, baskets, boxes, ties, poles,
piling, posts, handles and shingles constitute the main forest products
manufactured in the Piney Woods of East Texas.
Farther west, in East Central Texas, the post oak forests cover
approximately 5,030,200 acres in all or part of 39 counties.
The east and west “cross timbers”, occur on an area of approximately 3
million acres. The term “cross timbers” originated with the early
settlers who, in their travels from east to west, crossed alternating
patches of forests and prairies and so affixed the name “cross timbers”
to these forests.
Farther south in the Edwards Plateau region, are the cedar breaks which
extend over 3¾ million acres. Cedar grows on the steep slopes and
rolling hills common to this region, in association with live oak and
mesquite.
Other tree areas of the state include an estimated 500,000 acres of
mountain forests in the Trans-Pecos Region and the live oak area along
the Gulf Coast.
Two of Texas’ trees, guaiacum and ebony, produce the hardest woods in
the United States. Both species are found in the Rio Grande Valley. The
tree with the lightest wood in the United States, corkwood, grows near
the mouth of the Brazos River. Drooping or weeping juniper, so named for
the drooping characteristic of its branches, grows in the Big Bend area
but has not been reported to be native elsewhere in this country.
Catclaw, huisache, mimosa, baretta, pistache, black persimmon, Mexican
ash, anaqua, flatwoods plum (sloe) and guajillo are other trees common
only in Texas.