Sitka spruce is the world's largest spruce. The root system of Sitka spruce is shallow and platelike with long lateral roots with few branchings. Sitka spruce reproduces both sexually and asexually. Sexual maturity varies from 20 to 40 years.
Germination is epigeal.
Germination and seedling survival are greater on rotting logs then on the forest floor. Sitka spruce shows strong trends in hardiness and growth in relation to geographic origination. Sitka spruce reproduces asexually by layering. Sitka spruce has a stong affinity for soils high in calcium, magnesium, and phosphorus in the soil orders Entisols, Spodosols, Inceptisols, and Histosols. Flowering Fruit Ripens Seed Dispersal Alaska April to June late Aug. to mid-Sept.