Only one type of birch tree is native to parts of central Texas. While as many as 20 species of hawthorn trees grow in the state, not all have ranges that include the central region. Birch trees are members of the birch family (Betulaceae) and hawthorns are part of the large rose family (Rosaceae). Both types of trees grow in a variety of places in central Texas and have varied features. Some are useful as ornamentals.
Types and Geography
The sole birch species that grows in Texas is the river birch. It is found only in the far eastern portion of central Texas, typically in fertile soil associated with water, such as along lakes or stream banks.
Meanwhile, many hawthorn species grow in central Texas, including downy, littlehip, parsley, Reverchon and mayhaw hawthorns. The hawthorns occupy many ecosystems, from dry upland sites to moist wetlands.
Similarities exist between the river birch and many types of central Texas hawthorn species. For example, the leaves of the river birch bear close resemblance to those of some hawthorns. River birch foliage is triangular, with wedge-shaped bases and teeth along the edges. The Texas A&M University Texas Forest Service website notes that some hawthorn types also have leaves with these features.
In addition, some hawthorns have exfoliating bark, somewhat like the peeling, showy bark of the river birch.
The river birch typically stands about 40 feet high but can reach heights of 90 feet. The trunks of the tree are generally 8 to 10 inches wide.
Most hawthorn trees are 10- to 20-feet tall, with some appearing to be large shrubs. Some can grow larger, such as the cockspur hawthorns in central sections of eastern Texas. According to the "National Audubon Society Field Guide to Trees," they can be 30 feet in height and have trunks a foot in diameter.
One feature that many hawthorns have is thorns. The Gregg hawthorn, which grows in the plateaus of central Texas southward into Mexico, has many straight spines interspersed on its branches. Some of the spines on Texas hawthorns are large. Those on the downy hawthorn, for instance, can grow to lengths of 2 inches, reports the "Trees of North America" site. The thorns can become a danger when these hawthorns are used as ornamentals in your yard.
The river birch has a reputation as a premier ornamental species, with its colorful peeling bark and attractive leaves and form adding to its appeal. River birches make excellent specimen trees, and their affinity for damp places allows you to use them near ponds and wetlands on your property.
Hawthorns also have ornamental usage in Texas, with such types as the green hawthorn used in hedges and screens. Some hawthorns have the added benefit of producing edible fruit. For example, the riverflat hawthorn produces fruit by late spring that people use in making preserves and jellies.