This species is monoecious, with male and female flowers on a single plant forming on slender, tassel-like structures near the edge of branchlets. The tree flowers in April and the seeds ripen in October. The male and female strobili are produced from buds formed in late autumn, with pollination in early winter, and mature in about 12 months. Male cones emerge on panicles that are inches long. Female cones are round, resinous and green while young. They then turn hard and then brown as the tree matures. They are globular and in diameter. They have from 20 to 30 spirally arranged, four-sided scales, each bearing one, two, or rarely three triangular seeds. Each cone contains 20 to 40 large seeds. The cones disintegrate at maturity to release the seeds. The seeds are long, the largest of any species of Cupressaceae, and are produced every year, with heavy crops every 3–5 years. The seedlings have three to nine, but usually six, cotyledons each.