Trip Report: Exploring Austin, part 4

I've written about finding interesting Bauhinia, Catalpa, and Persimmon trees in the Austin area in previous posts.

Mexican Buckeye (Ungnadia speciosa)

On my first morning in Austin I went to a small natural area known as Stillhouse Hollow Nature Preserve, nestled into a neighborhood. The sign at the entrance told about an endangered species, the Karst Invertebrate, which lives in limestone caves. This area is also home to the endangered bird species Golden-cheeked Warblers and Black-capped Vireos. There is a nice path through this park and then an overlook. Near the overlook are signs asking that people stay on the path and respect the native flora and fauna, one of which is this endangered species living underground. I would have loved to explore off the path and find this little cave dweller, but I stuck to the rules and observed from the path only.

Mexican Buckeye (Ungnadia speciosa) seed pod

One item of interest off the path and out of reach was a shrub that had distinct seed pods. After using iNaturalist to identify this as a buckeye I assumed this was a species that I had seen in bloom once or twice before, one of the Aesculus genus. However, I learned that this was a Mexican Buckeye (Ungnadia speciosa). Thankfully even though this plant was well off the path, I came across this plant at nearly every other park I visited in the Austin area and was able to collect seeds from other plants.

Photo by iNaturalist observer caliche_kid.

I researched germination methods for each of the species I brought home. Most require some form of cold stratification and spring planting. This species was the exception, suggesting germination of fresh seeds. I went ahead and planted some of the seeds, setting aside some others to try in the spring if this first batch wasn't successful. In the week after planting the seeds we had consistent rains every few days - unusual for August. After just 10 days I noticed that the seeds had sprouted and were growing vigorously.

Mexican Buckeye (Ungnadia speciosa) seedlings - off to the races!
10 days after planting

Mexican Buckeye (Ungnadia speciosa) seedlings.

15 days after planting.

I'm not exactly sure where I will plant these bushes. From what I can find online they are probably only hardy in zones 8 and greater, but I think my parents' land near Lake Texoma (zone 7b) might work. I'll probably wait to see how many plants I have. If I have plenty then I'll test some in that climate and keep others potted in my greenhouse as insurance.