Seed Preparation
Stems were stored in a cool, dry environment for no more than 90 days before we manually separated seeds by type. Chasmogamous seeds were shaken from inflorescences and manually extracted with forceps when necessary. We tested three approaches to separating cleistogamous seeds. Most were manually extracted from stems by carefully slicing the stems so as not to damage seeds before removing them either individually or as a group when possible. However, we also soaked a random subset of stems containing both cleistogamous and chasmogamous seeds in room temperature tap water to facilitate cleistogamous seed extraction and sorting with a light table, hereafter referred to as soaked seeds. We compared these to an additional randomized subset of cleistogamous seeds that were still enclosed within the stem but separated into individual seed units, further facilitating seed processing, hereafter referred to as sheathed seeds. Once we extracted all seeds, we randomly weighed a subset of non-soaked or sheathed chasmogamous and cleistogamous seeds (~20 each) from each maternal plant to calculate average seed weights by maternal plant.