Plate 1 – Sequoiadendron giganteum, General Sherman Tree

Sequoia national park in California is a vast area of forest and woodland covered by some of the most historic significance, sequoia is the second oldest park in the world and started being introduced as a park in early 19th century (1803) when it was guarded by cavalry captain called Parkers.

Plate 2-Parker trees in sequoia, a very bright red of brilliant size sitting together, with the bark beaming off the light, one of the best views in the park.





Plate 3 – close up at parker trees, where bark was come off, due to excess forest firers.

Sequoia national park is home to the largest tree in the world by volume, shown by plate 1, there are other trees in the world that are taller however, a unnamed sequoia reaching 311ft compared to the ‘The General Sherman tree’, which is 275ft, however it does also have the record for the largest and biggest base at 35ft in diameter, a huge size showing the history and dominance of the sequoia trees. ‘The General Sherman Tree’ is about 2,000 years old with some sequoia in the park reaching over 3,000 years old, these are the oldest trees known to man, and have been able to reach high levels of evolution.

Sequoia Trees have far exceeded trees of the rainforest in trunk size with some reaching 5 meters, with a lot fewer trees compared to a rainforest, rainforest tend to have lots of small trees and thin trees, spread over a huge area. Generally spread over a large area, for example at the National sequoia park, most of the trees are the great, ponderosa pine (Pinus ponderosa), see plate 2, which grow in much more favorable conditions.

plate 3- Pinus ponderosa, A tree with 3 needles per fascicle, with a purple immature cone colour and a large trunk at the bottom. The bark has a very interesting effect, like a puzzle as the bark cracks all the way up.

Evolutionary effects and botanical aspects of ‘Sequoiadendron giganteum‘

Most conifers including sequoia have had to develop and produce longer tracheids, these are elongated cells in the xylem that help transport water through the tree, they also help give mechanical structure throughout the plant as they have a secondary thickening known as lignified cell wall, these are shown by the annular rings.

Adaptions have been noted for survival adaptions such as thick corky bark which alllow survival, such as pinus ponderosa (plate 3), Quercus macrophyll and Larix occidentalis, sequioadendron giganteum. The seedlings of sequioadendron giganteum (giant redwood) germinate most intensively after ground fires (Huston, 1994).

Sequioadendron giganteum is monoeciuo, meaning it has both male and female cones, cones start to develop when the tree is about 20 years. Each cone yields an average of 230 seeds, a large tree may be expected to have at least 11,000 cones, which are small about 5-7cm in length.

Soils and topography



Most redwoods grow on a granite residual (parent material) grove and alluvium soil. They grow best in deep sandy loam with a low CEC (Cation exchange capactity) and bulk density (Weatherspoon, C. Philip. 1990).

Fire Adaptions

Rapid growth

fire resistant bark

self pruned lower branches

Fire induced seed release

Hot air produced by fires, reaching high into the canopy results in the release of large quantities of seed over small areas. The increased seed fall caused by the fire related seedbed conditions become favorable for seed germination and seed survival.

Seedling Development

Seed reproduction is an relative unsuccessful process with the sequoia, even with the large numbers of seeds dispersed few numbers contain the conditions necessary for establishment.

There is no account of seed dormancy, surviving seeds will germinate as soon as the conditions are right. The most important factor in the germination of the ‘sequoiadendron giganteum‘ high levels of moisture in the air and protection of the seed from desiccation (when the plant drys up and causes leaves to fall to the ground, a major cause of sequoia seeds not germinating). This moist atmosphere is provided by a fine layer of moist and friable mineral soil.

Sequoia effects to competition

The sequoiadendron giganteum is shade intolerant all the way through its life as well as its neighbour the ponderosa pine (Pinus ponderosa), whereas the incense ceder (Calocedrus decurrens) is is slightly more tolerant of partial shade and is able to survive in different conditions. Another way forest fires help the sequoias and pines alike is by creating a more open canopy and help them develop early in life. Once young sequoia have established themselves and adapted to the light, they become easily dominant, over competitors with rapid growth.

Fire damage

Large sequoias becuase of their thick and non-resinous bark are more resistant than other species, however repeated fires through the bark of the tree’s base will kill of the cambium and produce a blackened scar. Furthermore those scars open up entry for fungi attacking the tree dead material and causing rot.