P90223KCoastal redwood, Sequoia sempervirens, are remarkable stable trees. They rarely fall, which is how they get to be thousands of years old. They prefer to live in groups, where they mesh their roots together, and shelter each other from wind. Those that live outside of a group stay shorter than forest trees, and typically develop multiple trunks that function as a group.

However, they are also remarkably weak in regard to their structural integrity. Limbs are easily broken away from their vertical trunks by wind. Snow, which is rare within their natural range, causes significantly more damage than wind, which is probably why their natural range does not extend into snowy climates. Trees with co-dominant leaders (double trunks that divide from single trunks above grade) have potential to split at the union of the double trunks. Such unions are typically at such acute angles, that the trunks press against each other rather than fuse together through impenetrable compressed bark.

Leaning redwoods such as these that were shown earlier this morning, are potentially hazardous, not because they are likely to fall over, but because they might be likely to break. The trunks are designed to support weight vertically. The asymmetrical distribution of weight supported by these two trunks exerts inordinate lateral tension on the trunks. To make matters worse, the trunk to the left is divided into two co-dominant leaders, although the union does not appear to be at a typically acute angle. (The lower trunk is now behaving more as a big limb than as a secondary trunk.)

I would guess that these two trees are genetically identical trunks from the same root system. Such seemingly pliable trunk structure is uncommon, and it is very unlikely that two such similar trees would just coincidentally appear within such minimal proximity to each other. Redwoods often develop multiple trunks from the same root system, particularly as they regenerate after harvest.

The good news is that these two trunks have survived like this long enough to develop ‘reaction’ wood, which is just like it sounds; a bit of extra wood to compensate for compression on the inside of the bend. Also, they are sheltered from wind by the other redwood in the forest around them.

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6 thoughts on “Redwoods Are Family Oriented

  1. I read this past year about how trees work with each other. if one is int trouble, another will send nutrition. They can also warn each other about disease (chemically, of course; this ain’t Babes in Toyland). So hearing they weave their roots together is interesting.

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    1. The native people who lived here a very long time ago revered their family values.
      Coastal redwoods happen to be among the few specie that survive fire by being resistant to it. Before their forests were harvested and regenerated with so many other trees mixed in, they were not so combustible. They excluded other trees by shading them out, and by preventing their seedlings from germinating. Therefore, they are not as nice to others as they might seem to be. (Most trees and other specie here use fire to their advantage, rather than resist it.)

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    1. The redwood forests were harvested for timber to rebuild San Francisco and adjacent regions after the Great Earthquake and Fire of 1906, and then to build much of the urban sprawl of the Santa Clara Valley. Our local forests were harvested early because of the proximity to the development. Because redwood regenerate so aggressively, I doubt that new trees are grown for reforestation like pines and firs are. If so, such trees would be grown from seed from trees that are endemic to each particular project. We grew redwoods on the farm only for landscape purposes, but such trees are ‘garden variety’ trees, which are cloned by cutting. ‘Soquel’ is the standard cultivar. They are much easier to grow from cutting than by seed. They are even easier to grow from burl suckers. The suckers can be peeled off of the burls with callus grown already producing roots. Years ago, rooted burl suckers could be purchased at airports and trains stations as souvenirs of California. Sadly, they do not like the climates outside of their native range; although they can grow as odd houseplants, and can survive for centuries as bonsai.

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  2. Here in central Pennsylvania my mother makes a mission to pot up and share Dawn Redwood trees. Hundreds, I’m sure! Mom celebrates her 89th birthday in March. Hers show no trouble going through four seasons, their fresh green in early spring, changing to deep orange in fall, reaching dizzying heights with straight centers.

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    1. Dawn redwood was a fad here in the 1990s, The fad sort of ruined it for some of us. Besides, it does not compare to the native coastal redwood. There is a tall specimen at work that is designated as a historic tree. There is also a giant redwood right nearby, with the native coastal redwoods all around. There is a plaque explaining the differences between the tree. It is nice to have them all in the same spot.

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