With all these attributes, it might seem tempting
to plant many more escarpment oaks. It would
be tempting to plant more tough bur oaks (Q.
macrocarpa) as well. However, San Antonio is
overly stocked with oaks, pecans, and cedar
elms, according to Holinsky. The oaks (Fagaceae
family) are vulnerable to oak wilt, and cedar
elms (Ulmaceae family) can get native elm
wilt. Holinsky is trialing trees outside of these
genera, like Kentucky coffeetree (Gymnocladus
dioicus, in the Fabaceae family) and catalpa
(Catalpa bignonioides, in the Bignoniaceae
family). "These trees are showing promise
for us, for their heat tolerance," he says.
Established Mexican sycamores (Platanus
mexicana), native to northeast and central
Mexico, have been weathering the drought
well, according to Holinsky. Mexican syca-
more evolved in dry, rocky, alkaline >>
According to the 2023 USDA
Hardiness Zone Map, San Antonio,
Texas falls in Zones 8b (15°F to 20°F)
(-9.4 C to -6.7 C) or 9a (20°F to 25°F)
(-6.7 C to -3.9 C) depending on the
elevation and microclimate of the
part of the city one finds oneself in.
An iconic Texas live oak (Q. fusiformis) at the historic Alamo in San
Antonio. Photo by Rei, Wikimedia Commons, CC BY-SA 3.0
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