Pacific madrone (Arbutus menziesii) seeds can be extracted and cleaned in a procedure which utilizes a mortar and pestle, a blender with a rubber blade, and several sieves. The method involves several steps but is not difficult and can result in a large amount of seed in a short period of time. Following extraction, the seeds can be dried and stored at low moisture content (6%) in sealed containers at 3-5°C or given a cold strati cation treatment and then sown. Cold stratification periods of 60 days or longer increased the initial rate of germination compared to seeds stratified for 40 days but resulted in seed losses due to premature germination during stratification. For lots from the Puget Sound Lowlands, cold stratification for 40 days is adequate; seeds in stratification longer than 40 days should be monitored closely for premature germination.
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