Seeds of Pinus aristata Engelm., bristlecone pine, from the type locality at the headwaters of Clear Creek in Colorado have a germination of 80 percent. Germination occurs within 10 days with or without vernalization. Scarified seeds are invaded by fungus and less than 10 percent germinate. Seedlings 10 and 180 days old do not survive exposure to −10C (14F) even when exposed to gradually decreasing temperatures to −4C (25F) for five weeks before treatment. Rapid germination, scarification mortality, and lack of cold hardness in seedlings work against the reproduction of bristlecone pine.
Reid, William H.
"Germination of Pinus aristata Engelm.,"
Great Basin Naturalist: Vol. 32
, Article 10.
Available at: https://scholarsarchive.byu.edu/gbn/vol32/iss4/10