13. Saving South Texas Milkweed: Conservation, Pollinators, and Hope for Asclepias Prostrata

Brought to you by Grow Milkweed Plants

This YouTube video transcript details a three-year research project on Asclepias prostrata, a federally endangered milkweed species in South Texas. The research investigated the plant's distribution, soil preferences, pollinators (including a newly identified wasp species), and successful seed germination techniques. Habitat loss from urbanization, agriculture, and border wall construction threatens the plant's survival. The presenter suggests collaborations with energy companies to utilize cleared land around wind turbines as potential habitat for restoration efforts. High seed germination rates were achieved, offering hope for future conservation.

Understanding Asclepias prostrata: An Endangered Milkweed in South Texas

Source 1: U.S. Fish & Wildlife Service (FWS), "Endangered and Threatened Wildlife and Plants; Endangered Species Status for Prostrate Milkweed and Designation of Critical Habitat"

• Official Listing and Habitat Designation: This section provides a brief overview of the FWS's ruling, which officially classifies Asclepias prostrata as endangered and outlines the designation of its critical habitat in Texas. The document details the legal basis for these actions and where to find the full ruling.

Source 2: Crime Pays But Botany Doesn't, "The Rarest Milkweed in Texas"

• Introduction and Discovery: The author introduces Asclepias prostrata and describes its perennial nature, preferred habitat, and the factors contributing to its decline, mentioning the initial discovery by Mark Fishbein.
• Botanical Observations and Adaptations: This section focuses on the plant's physical characteristics, such as its leaf shape, stem texture, and adaptations to the arid climate of South Texas. The author provides detailed descriptions of the plant's features, highlighting its unique morphology and adaptations for survival.
• Habitat Description and Coexisting Species: The video shifts to showcasing the plant's habitat, including other plant species found within the same environment, such as various legumes, hibiscus, and cacti. The author emphasizes the importance of understanding plant communities and interactions within a specific ecosystem.
• Threats to Survival: The author discusses threats to the plant's survival, including habitat destruction due to road grading, land clearance, and invasive species like buffelgrass. The author criticizes the proposed border wall, highlighting its potential negative impact on the already fragile ecosystem.
• Additional Observations and Reflections: This section features observations of various insects interacting with the milkweed and other plants, including swallowtail butterflies, wasps, and pollinators. The author delves into ecological relationships, emphasizing the interconnectedness of species within a habitat.
• Final Observations and Advocacy: The video concludes with observations of additional Asclepias prostrata populations, emphasizing their precarious situation. The author reiterates the need for conservation efforts and expresses concern over human activities impacting the plant's future.

Source 3: The University of Texas Rio Grande Valley (UTRGV) Graduate College, "Understanding the Distribution and Abundance of Asclepias prostrata in South Texas with Liz Gonzalez"

• Introduction and Research Objectives: Liz Gonzalez introduces her research, focusing on the distribution, abundance, and threats to Asclepias prostrata, highlighting its recent listing as federally endangered and the need for better understanding its ecological requirements.
• Background and Conservation Status: Gonzalez provides background information on the plant's taxonomy, life cycle, preferred habitat, and its ranking as critically imperiled. She discusses the various threats to the species, including habitat loss due to urbanization, agriculture, energy development, and the construction of border walls.
• Soil Mapping and Habitat Suitability: Gonzalez explains her use of soil mapping to identify potential areas of suitable habitat for the plant within protected lands. She details the soil types associated with Asclepias prostrata occurrences and maps their presence on U.S. Fish and Wildlife Service properties, suggesting these areas could be used for restoration efforts.
• Field Observations and Phenology: Gonzalez shares her observations on the plant's growth patterns, noting its preference for full sun exposure and tolerance for high temperatures and low rainfall. She discusses variations in the plant's appearance, including color changes and shade avoidance syndrome when growing in less ideal conditions.
• Pollination Ecology and Insect Interactions: This section explores the plant's pollination mechanism, its reliance on outcrossing for reproduction, and the identification of potential pollinators. Gonzalez discusses the challenges in identifying effective pollinators and highlights the importance of insects like spider wasps in the plant's reproductive success. She also documents the monarch butterfly using Asclepias prostrata as a host plant.
• Extraction, Transplantation, and Root Morphology: Gonzalez describes the unplanned extraction and transplantation of Asclepias prostrata from a ranch slated for border wall construction. She details the process, emphasizing the careful extraction methods used to preserve the plants. Observations about the plant's underground root system, including taproot length and the presence of energy-storing tubers, are shared.
• Seed Viability and Germination Experiments: This section delves into Gonzalez's investigation of the viability and germination rates of Asclepias prostrata seeds. Comparing her findings to closely related milkweed species, she outlines her experimental methods, including seed collection, storage, germination techniques, and the use of clipping to enhance germination success.
• Concluding Remarks and Conservation Recommendations: Gonzalez concludes by emphasizing the need for continued research and conservation efforts for Asclepias prostrata, given the ongoing threats to its survival. She proposes innovative strategies for habitat restoration, including partnerships with energy development companies to utilize cleared land around wind turbines as potential habitat for the plant. She advocates for the importance of public awareness, collaboration with landowners, and securing funding for further research and conservation initiatives.