High germinability can facilitate recovery of Adelia vaseyi (Euphorbiaceae), an imperiled Tamaulipan thornscrub shrub

While critical to maintaining dryland biodiversity and drought resilience, reforestation has been limited in subtropical dry forests because of knowledge gaps in seed biology that must be filled to upscale seedling production and ensure recovery of imperiled endemic plants. We characterized seed germination, dormancy, and storage needs for Adelia vaseyi, a threatened endemic shrub commonly included in planting mixes to restore Tamaulipan thornscrub, an imperiled subtropical forest spanning South Texas and Northeastern Mexico. We found A. vaseyi seeds have high germinability (82.0%) and a short mean germination time (3.04 ± 0.08 days). A delia vaseyi seed does not appear to have physical or other dormancies and may have orthodox behavior maintaining their viability with a moisture content of 6.7%, which is adequate for long-term storage. Our results indicate that A. vaseyi can be readily propagated in nurseries and seed banked for future recovery actions. Conversely, its high germinability and lack of dormancy hint there are no inherent constraints to germination, suggesting that natural seedling recruitment may instead limit population growth in the wild. Therefore, reforestation with nursery-grown seedlings of A. vaseyi may be necessary to support recovery of this threatened shrub.