Application. Stratification of red alder seeds is recommended to improve the speed and possibly completeness of germination if temperatures are expected to be less than optimum such as in the case of most outdoor nursery beds in the Pacific Northwest of the United States in early spring . In the case of seedling production in greenhouses, we suggest that temperatures be regulated to achieve optimum germination results .Abstract . Two-to four-week stratification of red alder seeds slightly increased the speed of germination but did not improve total germination under alternating warm temperatures (30 °C/20 °C), yet significantly improved speed and total germination under cool temperatures (15 °C/5 °C) that simulated early spring outdoor nursery bed conditions . Only seeds that received four-week stratification achieved complete germination at the cooler temperatures. Strong seed source variation in response to seed treatments was observed at the cool regime. The Yacolt source germinated well regardless of seed treatments, even without stratification, while five other sources needed two to four weeks of stratification to achieve above 50% germination . Possible reasons for this variation are discussed .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.