Pre-treatment: Seeds are placed in fine mesh bags into a 1% hydrogen peroxide (3:1 water/3% hydrogen peroxide) soak for 24 hours, rinsed, and placed in water for an additional 24 hours. The bags are placed in sealed containers in refrigeration at 1 to 3 °C for 30 days. Seeds should be checked weekly for mold and treated with 1% hydrogen peroxide if needed.

Establishment: Female cones are green and mature to brown. Generally ready to collect in the fall. They start to produce seed relatively early. They produce seed every year but is heavier every 4 to 5 years. Grows well in average, moist but well-drained soils in full sun/part shade. Needs to be sheltered from wind. Does best in areas with warm, dry summers and cool, wet winters. Found in California and Oregon, mostly from Coos Bay to the Klamath river with some additional isolated populations near the Trinity Mountains and Mount Shasta.

Source: npn.rngr.net