Sheffield's Seed Company Page

Discover the remarkable adaptability and unique charm of Knobcone Pine (Pinus attenuata), a fascinating tree indigenous to the mountainous, serpentine soils of California and Oregon. Renowned for its knobby pine cones, which persistently cling to branches for up to 20 years, this species has perfected the art of survival through fire-adapted reproduction. When fires reach 200°F, the heat melts the resin sealing the tightly closed cones, allowing seed dispersal and ensuring the continual regeneration of the forest. Knobcone Pine, typically growing to heights of 26–79 feet, can even manifest as a shrub on less fertile sites, demonstrating an impressive adaptability. Its dense, multi-trunked growth is a natural testament to resilience, thriving in poor soils where few others can. This species forms nearly pure stands and interacts, albeit rarely, through hybridization with other pines. Explore how this resilient tree not only thrives in its ecosystem but also plays a pivotal role in soil genesis and nutrient cycling, creating environments rich in nitrogen and phosphorus post-fire.