Switchgrass Seed Dormancy and Stratification
The seed of switchgrass is very small and has a hard seed coat. A high percentage of newly harvested seed is usually dormant. Newly harvested seed can have little as 10% germination or less. However, aging for a year, storage in warm temperatures, or treating it with water and chilling temperatures either through manual or natural stratification will break dormancy. Stratification is the process of subjecting seeds to both cold and moist conditions. Many seed species undergo a dormancy phase, and generally will not sprout until this dormancy is broken through stratification. Seed dormancy is usually overcome by the seed spending time in the ground through a winter period and having its hard seed coat softened up by frost and weathering action. By doing so the seed is undergoing a natural form of stratification. This cold moist period stimulates the seed embryo. Its growth and ensuing development eventually break through the softened seed coat in its search for sun and nutrients.