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The seeds of difficult-to-germinate native species of American licorice (Glycyrrhiza lepidota Pursh), angelica (Angelica atropurpurea L.), wild blueberry (Vaccinium angustifolium Ait.), wild mint (Mentha arvensis L.), and purple coneflower (Echinacea angustifolia D.C.), were soaked in 0, 2.5, 5.3, or 7.6 m KOH solutions for 0, 1, 5, 10, 15, or 20 minutes. After these treatments, germination was determined at 10 °C with a 14-hour photoperiod in petri dishes and seedling emergence was conducted at 14/10 °C with a 14-hour photoperiod in a sandy loam soil. In general, KOH treatment for only 1 min enhanced germination and seedling emergence. The optimal KOH concentration and soaking time in improving seed germination and seedling emergence varied with species, being 5.3 m and 10 min for purple coneflower, 5.3 m and 5 minutes for wild blueberry, 7.6 m and 5 minutes for angelica, 7.6 m and 1 minute for wild mint, and 5.3-7.6 m and 10 minutes for American licorice, respectively. Prolonged soaking, particularly in high concentrations, reduced germination and emergence.