Tree Images and Identification

Texas Forest Service, Trees of Texas banner

The Texas Forest Service Trees of Texas portal helps users identify both native and non-native trees in Texas.

NPIN logo


The Ladybird Johnson Wildflower Center provides images of over 277 trees found in Texas.

Houston's Tree Population

Table 1. Most Common Tree Species (10 Million or More Trees)

Tree Species Number% of All Trees*
Chinese Tallow 152,498,00023.0
Loblolly Pine 123,974,00018.7
Cedar elm 45,546,0006.9
Water oak 35,608,0005.4
Hawthorn31,771,0004.8
Sweetgum30,699,0004.6
Sugarberry26,788,0004.0
Green ash 24,388,0003.7
Baldcypress21,628,0003.3
Willow oak20,993,0003.2
Red maple 17,162,0002.6
American hornbeam 11,809,000 1.8
Southern red oak 11,322,0001.7
Black tupelo
10,436,0001.6
Table from Houston's Regional Forest Report , US Forest Service, 2005, pg 9.

*Region-wide average

Houston Area Regional Forests

The Houston Metropolitan regional tree population consists of 663 million trees. Thirteen percent, or 84 million trees, are found in areas classified as "urban" and the remaining trees are classified as "rural" with 71% located in forests and 12% in agricultural/range lands.

Houston Region Land Cover Map, map by the Houston Advanced Research Center using NOAA C-CAP 2005 dataHouston Region Land Cover Map [Figure: Houston Advanced Research Center using NOAA C-CAP 2005 land cover data].


Threats to Houston's Forests

Four insect pests have been identified as major threats to Houston's trees.  These are the gypsy moth (Lymantria dispar), southern pine beetle (Dendroctonus frontalis), Asian longhorned beetle (Anoplophora glabripennis), and the emerald ash borer (Agrilus planipennis). An infestation of any of these 4 insects is capable of causing billions of dollars worth of damage.

The Chinese tallow (Triadica sebifera) is the most important invasive tree species in the Houston region.  As of 2005 this species accounted for more than 152 million trees (23%) in the region.  In the southern portions of the Houston Metropolitan region, mostly in agricultural and range land cover types, Chinese tallow accounts for up to 80% of trees in the area.

The biggest threat to Houston's tree population is conversion of forests to residential/urban lands. Urban expansion in the region from 1992-2005 was the major factor behind a 24% decline in forested area in the Houston region.

Table 2. Change in Houston Regional Tree Cover from 1992-2005.
Year Sq. Mi of Forest % of Total Region Area 
Sq. Mi. Loss per Year
1992
2,817
 32.02%-
1996
2,386 27.12%107.7
2001
2,226
 25.29%32.2
2005
2,137 24.29%22.0
Table from Counting on Quality of Place: Air Quality, Parks & Trails, Trees, Center for Houston's Future, 2009, pg 33.


Urban Forests: Ecosystem Services

Urban trees provide many benefits to their surroundings.  Click each image to see a schematic of each ecosystem service provided by trees.

Mitigate Urban Heat Island Effect
Schematic of Urban Heat Island Effect

Reduce Stormwater Runoff
Schematic of Trees and Stormwater Management

Lower Energy Use
Schematic of Energy Conservation from Trees

Sequester Carbon Dioxide
Schematic of the Role of Trees in Carbon Sequestration

Scrub Air Pollution
Schematic of Air Pollution Scrubbing by Trees

Other services include noise pollution reduction and aesthetic and social benefits.

The NBII Program is administered by the Biological Informatics Program of the U.S. Geological Survey
About NBII | Accessibility Statement | NBII Disclaimer, Attribution & Privacy Statement | FOIA
Science.gov Logo       USGS Logo       USAgov Logo