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Chapter 1
“Land of
Contrasts”
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Sizing Up Texas
• Every 10 years the United States is
required by the Constitution to count its
people, or conduct a census.
• According to the census of 2000, the
population of Texas is almost 21
million. That’s 7% of the total
population of the United States.
• There are approximately
85 people per
square mile.
Why is it important to know how
many people reside in the state
and where they reside?
• Members of the House of
Representatives are chosen based
on the number of people in the
state. To ensure that people are
equally represented, officials must
know how many people are in the
state and where they reside.
• Texas is comprised of 254
counties.
• More than half of the population
lives in only 8 of them.
• The least populated county in
Texas is Loving County. It has a
population of 67.
• The most populated county in
Texas is Harris County. It has
about 3,400,000 people.
Loving
Pop. 67
Harris
Pop.
3,400,000
nd
2
Texas is the
largest state
in the U.S. Only Alaska is
bigger.
*The total area of Texas is
268,581 square miles.
* This is 7% of the total
area of the United States.
If you wanted to hike around the
boundaries of Texas, you would
have to walk 3,822 miles.
801
miles
Texas stretches
801 miles from
the northwest
corner of the
Panhandle to the
southeast corner
by the gulf.
773 miles
The state
stretches 773
miles from
west to east.
In contrast,
the coast along
the Gulf of
Mexico lies at
sea level.
Guadalupe
Peak is the
highest point
in Texas at
8,749 feet.
Orange
averages
59 inches
each year.
El Paso
averages 8
inches of rain
annually.
Rain, RainGo away!
The face of Texas
changes dramatically
as one travels from
the southernmost to
northernmost point.
(Map in text on page 32)
The southernmost point
in Texas lies on a mostly
level plain. This point is
very near sea level
where Texas meets the
Gulf of Mexico.
South Texas
Running along the southern
coast a few miles offshore is
Padre Island. This long thin
strip of land covered with sand
dunes is a barrier island
protecting the mainland shore
from ocean waves. The bay
between Padre Island and the
mainland is a rich fishing area.
Padre Island
Moving northward, the land
slowly rises and begins to
gently roll. This part of Texas
is covered with a tough and
prickly mixture of grasses,
mesquite trees, cacti,
blackbrush, and other plants
that thrive in a hot, dry
climate.
Cutting across Texas in a great
curving arc is an escarpment, or
long cliff. The Balcones
Escarpment, formed millions of
years ago by a giant earthquake,
follows a weak part in the earth’s
crust called a fault. Long ago, the
land sank east and south of the
fault. North and west of it, the land
rose many feet, forming the
escarpment.
The Balcones Escarpment
The Balcones Escarpment
marks the beginning of a
region of Texas known as the
“hill country.” This part of
Texas is a plateau, or
tableland, covered with small
trees and brush.
Hills on the rim of the plateau
were formed by streams
cutting and smoothing over
the plateau’s limestone
edges.
There are more streams and
rivers in this part of Texas
than in any other.
The land gradually gets flatter
and higher as you travel
northwest. One abrupt change
disrupts this plains region. The
Caprock Escarpment, also
formed along a fault, has cut
great gashes in the caprock.
Palo Duro and Tule Canyons
hold some of the most beautiful
scenery in Texas.
Palo Duro Canyon
A trip starting at the
easternmost point in the state
would also begin on a plain.
Again, the level of the land
gently rises as you travel
westward, After crossing the
Balcones Escarpment and the
hill country, you finally reach
the plains to the west.
West Texas has landforms
that do not appear in other
parts of the state. Most
noticeable are the mountains,
which are a part of the Rocky
Mountain Range. This part of
Texas has 91 mountains more
than one mile high.
Guadalupe Peak, at 8,749 feet above sea
level, is the highest point in the state.
“Wrong Way” Rivers of Texas
• Texas Rivers are sometimes
called “wrong way” rivers
because they carry water from
the dry part of the state, where
it is needed, to the eastern part,
which normally has plenty of
water.
To keep precious water
from running unchecked
into the Gulf of Mexico,
many rivers in Texas
have been dammed,
forming lakes.
Dam on Colorado River
The Rio Grande
The Rio Grande, which forms
the southern border of Texas,
is one of the longest rivers in
the United States – almost
2,000 miles in length.
The Rio Grande was formed
between 15 and 30 million
years ago, when forces within
the earth caused the crust to
drop forming a rift, or gash,
more than 5 miles deep in
places. The basins of the rift
filled with runoff rain and
snow to form inland seas.
Earthquakes caused the seas
to overflow, and the Rio
Grande was formed. The river
connected basin after basin,
finally reaching the sea about
a half-million years ago.
Texas Lakes
• Texas has nearly 200 lakes.
• Texas ranks third behind Alaska and
Minnesota in the surface area of its
inland waters.
• All but one of the lakes were formed
when rivers were dammed.
• Only Caddo Lake in East Texas
began as a natural lake. Now, even
Caddo Lake has been dammed.
Uses for Texas Lakes
•
•
•
•
•
Flood control
Water conservation
Irrigation
Water for cities and towns
Manufacturing
Aquifers
• Aquifers are another major water
source in Texas. Aquifers are
natural underground water
reservoirs, which are replenished
with rainfall. Enormous amounts of
water are pumped from the
aquifers to supply the water needs
of cities and irrigate farms.
The Edwards Aquifer
• The Edwards Aquifer is found
between the cities of Austin to
San Antonio. Large amounts
of rainfall refill this aquifer,
making it a dependable source
of water for years to come.
Barton Springs in Austin
•
Porous Limestone
Texas Blind Salamander
The Ogallala Aquifer
The future of this aquifer remains a
major concern. It lies beneath the
Texas High Plains, a region of Texas
that does not have a dependable
supply of rainfall. More than 5
million acres are irrigated by this
aquifer, and its levels continue to
decline.
Not every Texan is concerned
with protecting our water
resources.
Wastes and chemicals from
cities, factories, and fields often
empty into our rivers, lakes,
aquifers, and bays. Because of
this pollution, fish and seafood is
sometimes declared unsafe to
eat.
Three Vegetative Regions
In general, Texas has three
types of natural vegetative
regions:
I. forests
(for timber)
II. grasslands (for farming)
III. savannas (for ranching)
Forests
• Three major forest regions are found in
Texas, all in the eastern third of the
state where rainfall is greatest.
• Timber is one of the top cash crops in
Texas, usually outranked only by
cotton.
• The lumber, plywood, and paper
industries provide many jobs in East
Texas.
Grasslands
• Early settlers established farms on
the grasslands because they had
to clear only a few trees. These
areas are still major farming areas.
Grasslands
Soil is a valuable resource
• The rich soil of Texas is one of
its most valuable resources.
• Major crops include cotton,
spinach, watermelons, wheat,
rice, corn, soybeans,
vegetables, and peanuts.
Savannas
Much of central and west Texas
has a dry, rocky soil that
supports only short grasses
and small desert shrubs, and
in some places scattered trees.
Savanna
Desert Savanna
Land that is not suitable for
farming can often be used for
ranching. Texas usually leads
the nation in the number of
cattle, sheep, and goats
raised, and in the amount of
wool and mohair clipped.
Mohair
Natural Mineral Resources
• Texas is the nation’s most important
producer of minerals.
• It leads the nation in the production of
mineral fuels, with petroleum the most
valuable and natural gas the second
most valuable.
• One-fourth of all the energy produced
in the entire history of the United States
has been produced in Texas.
Other Texas Minerals
• Texas produces about 1/5 of the nation’s salt.
You can find salt mines and domes in many
parts of the state.
• Coal is found in north central and west
Texas. A low-grade coal, called lignite is
found along the coastal plain. Coal is used
to fuel boilers, steam-engines, and furnaces.
• Sulfur is used in insecticides and
gunpowder.
• Gypsum is used to produce drywall for
construction.
• Granite and limestone are used for building.
• Clay, lead, iron, magnesium, zinc, and
uranium are also mined in Texas.
Mining for Coal
The Climate of Texas
• Hot summers and mild winters
generally characterize Texas’s climate;
however, Texas covers such a large
area that other factors contribute to its
climate as well.
• These factors include:
I. Absolute location
II. Relative location
III. Elevation
I.
ABSOLUTE LOCATION
• Texas lies in what are called the
“middle latitudes,” the region about
midway between the equator and the
North Pole.
• Because Texas is not very far from the
Equator, it experiences warmer
weather. South Texas is milder than
North Texas.
I. Absolute Location…
• The middle latitudes are also a meeting
place of cool air moving from the north
and moist, warm air moving from the Gulf
of Mexico. Violent storms may result
from this mixing of cold and warm air.
These may produce thunderstorms, hail,
and tornadoes.
• Texas has an average of 153 tornadoes
each year.
Tornado
II. Relative Location
• The location of Texas relative to the Gulf
of Mexico has a major influence on the
climate of the state. Most of the year,
winds blow inland from the coast for 200
miles or more. These gulf breezes cool
Eastern Texas in the summer and warm it
in the winter.
• Moisture from the gulf is the source of
most of the rain that falls on our state.
Hurricanes and tropical storms also
originate in the gulf.
HURRICANE
Relative Location …
• In general, for each 17 miles from east
to west in Texas, annual rainfall
decreases by one inch.
• For example, the city of Orange in East
Texas averages 59 inches of rainfall per
year. El Paso, in West Texas, averages
less than 8 inches of rain per year.
III. Elevation
• In general, the average temperature
cools about 3 degrees for each 1,000foot rise in elevation.
• Mountainous areas receive more
rainfall because cooler air is less able
to hold moisture.
• On the northern plains, there are no
mountains to block powerful northers.
Rain on the Mountaintop
THE END