The first things you notice about a giant sequoia forest are the huge, orange trunks, bigger than any you have ever seen. The initial stage of climbing into the crown of a big tree seems like ascending a wall. Here Dr. George Koch pauses on his ascent of a 280–foot–tall tree.
The crown of a giant sequoia is even more impressive than its main trunk near the ground. Huge branches and limbs extend far from the trunk and carry great quantities of leaves. Here Marie Antoine pauses while crown–mapping a 298–foot–tall tree.
Like its close relative the coast redwood, giant sequoia responds to injury by reiteration. The distal portion of this limb broke off, but the proximal portion remains alive and supports reiterated trunks. Note the epicormic sprouts emerging from the side of the limb.
All old giant sequoias have been blasted by lightning and had their crowns burned in fires. This 283–foot–tall tree is no exception. Much of the upper trunk is dead and slowly decaying, but the tree has re–built a thriving crown with reiterated trunks.
Some of the most impressive giant sequoias have dead tops looming above their highest living leaves. Here George Koch glances up as I climb to the top to get a better view.
Killed by lightning and fire, the dead tops of giant sequoias persist for centuries in the sun, drying, cracking, and collapsing very slowly. The long–dead upper crown of this giant sequoia is still remarkably sturdy.
After being blasted and burned, giant sequoias can still reach impressive heights. Here is a view from the top of the tallest known giant sequoia, a 311.4–foot–tall tree with two large reiterated trunks emerging from a broken main trunk 250 feet above the ground. Only four other tree species on Earth are taller (Sequoia sempervirens, Pseudotsuga menziesii, Picea sitchensis, and Eucalyptus regnans).
In most groves, nearly every giant sequoia has living leaves above its highest piece of dead wood despite the fact that the tree’s top has died back many times.
Other tree species share the forest with giant sequoia, but none rival its height, size, resistance to fire and decay, or age. To me, giant sequoias seem to lord over the forest, taking little heed of lesser trees.
Giant sequoia groves are relatively small and end abruptly, giving way to mixed conifer forests that stretch on for many miles. Here is a view of the edge of a giant sequoia grove from above the highest leaves on a 280–foot–tall tree.
Like coast redwood, the bark of giant sequoia is inhospitable to most epiphytes, but exposed dead wood is often covered with lichens and a few mosses. The bright yellow lichen in this and other photographs is Letharia.
The seed cones of giant sequoia persist on the trees for decades and acquire an interesting community of lichens. The pale gray lichen in this photograph is Hypogymnia.
Dead leaves, bark, and wood accumulate in crotches and fire caves and contribute to limited soil development in giant sequoia crowns. Many plants that normally grow on the forest floor occasionally occur as epiphytes on giant sequoia, such as this Quercus seedling and the herb Gallium.
Ribes shrubs, whose fruits are dispersed by birds and mammals, are common epiphytes in fire caves of giant sequoia crowns.
Conifer saplings rarely occur as epiphytes in giant sequoia crowns. Here Cameron Williams inspects the relatively expanded leaves of a giant sequoia sapling rooted in soil on top of a dead branch stub 200 feet above the ground.
