The bark of Giant Sequoias are very fire resistant. The thick, fibrous, cinnamon-red bark contains tannin, a natural fire extinguisher, which also is suspected to inhibit wood borers and fungi. The outer bark can be up to 24 or more inches thick and is completely lacking of resins, making it essentially fire proof. It is reported that the General Sherman in the Sequoia National Park has outer bark in excess of 4 feet thick. There are current investigations as to what extent these wounds and mechanically induced wounds serve as infectious courts for insects and disease.
Sequoia cones are serotinous, releasing seed only when subjected to extreme heat.
The cones of the Giant Sequoia are surprsingly small, obtaining a maximum length of only 9 cm. The cones take in excess of 2 years to mature and may remain on the tree up to 20 years. The Giant Sequoia develops on average 1,500 cones per year. Hot air created by fire is convected high into the canopy and stimulates the cones to dry, open, and finally release seeds. The larvae of the beetles mine in the fleshy part of the cone and as a result, sever the vascular connections and ultimately free the seeds from the cone.