Federal and State Listed Species of Texas:
Texas snowbell are native to the drainages of the Nueces and Devils rivers in Edwards, Kinney, Real, and Val Verde counties on the western Edwards Plateau of Texas. They have been introduced in Uvalde County.
Texas snowbell is a deciduous shrub that emerges single-stemmed, but as it matures, grows multiple stems from its base. The plant is 1 to 6 m tall with smooth, gray bark and almost round leaves (2.5-7.5 cm across). Leaf edges are smooth or slightly wavy. The leaves are bright green and hairless on the upper surface, but have a thick layer of microscopic star-shaped white hairs on the lower surface. Leaf veins are arranged in a feather-like pattern, with one main, prominent vein in line with the leaf stalk and multiple smaller veins branching off the main vein. Usually 3-5 flowers hang downward from the same flower stalk, which arises from the same point as a leaf. A very pale green, bell-shaped structure (4-6 mm long and 4 mm wide) cups the base of each hanging flower. The five white flower petals are narrowly oval and 14-20 mm long. Ten male reproductive structures hang from the center of the flower, bearing bright orange pollen. A round, three-sectioned, 7-12 mm wide fruit eventually splits open to reveal (usually) one shiny brown seed.
Without flowers, Texas redbud (Cercis canadensis var. texensis) can be confused with Texas snowbell, except that the lower leaf surface is hairless in Texas redbud, and it has multiple prominent leaf veins radiating out from the point where the leaf attaches to its stalk. Three other closely related snowbell occur in Texas: hairy sycamore-leaf snowbell (Styrax platanifolius ssp. stellatus), sycamore-leaf snowbell (Styrax platanifolius ssp. platanifolius), and Young’s snowbell (Styrax platanifolius ssp. youngiae). Young’s snowbell is only found in West Texas, whereas the other subspecies have overlapping ranges in the Edwards Plateau. Below are tables that can be used to distinguish between the four subspecies, depending on available material. If possible, always use as many characteristics as possible to identify plants.
|Plant Name||White, star-shaped hairs on flower stalk?||White, star-shaped hairs on calyx1 edges?||Density of glands2 on calyx1 edges||Calyx1 edge tooth length||What % of the stigma3 is hairy? (starting from the end attached to the flower)|
|Texas snowbell||yes||yes, thin layer||dense||<1 mm||15-35%|
|hairy sycamore-leaf snowbell||yes||yes||dense||<1mm||50-70%|
|Young's snowbell||yes||yes, thick layer||dense||<0.6 mm||
- 1calyx: green leaf-like structures cupping flower
- 2glands: a small structure that drips substances or looks like it drips substances; in the case of snowbell, glands are minute, red-brown, globular, and have a rough surface
- 3stigma: stalk extending beyond pollen-bearing structures in flower center
|Plant name||Leaf edge||Lower leaf surface hair present?||Scattered hairs on upper leaf surface?|
|Texas snowbell||smooth or slightly wavy||yes, thick layer||no|
|hairy sycamore-leaf snowbell||usually a few, irregular, rounded teeth||yes, but scattered and sparse||yes|
|sycamore-leaf snowbell||usually a few, irregular, rounded teeth||no||no|
|Young's snowbell||smooth, slightly wavy, or a few, coarse teeth||yes, thick layer||yes|
Texas snowbell grow on limestone cliffs, slopes, and gravel streambeds along permanent or periodic waterways.
Life Cycle Events
Flowering occurs from March to April and fruiting begins in April with fruits ripening and releasing seed in late summer or early fall. Germination occurs in spring.
For the most accurate identification, Texas snowbell should be identified while in bloom in March and April.
- Rare Plants of Texas
- U.S. Fish and Wildlife Service
- Flora of North America
- Center for Plant Conservation
- Fulton, S. 2010. Status assessment and ecological study of Styrax platanifolius ssp. texanus. Section 6 final report. Austin: Texas Parks & Wildlife Dept..
- Poole, J.M. 1993. Reproductive biology of Texas snowbells (Styrax texana). Section 6 final report. Austin: Texas Parks & Wildlife Department.