Coastal 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.
2. These two bigger stumps are just a short distance uphill and across the small creek. Old stumps are more often single, but surrounded by multiple trunks that emerged from the roots. Because almost all of the trees here had been harvested about a century ago, there are now many more secondary trunks per area than there would naturally be. It is not much of a problem yet, but these trunks will likely become more crowded as they mature.
3. These are the same two stumps from the other side. This trunk coming up from within is likely from the same original root system. All trunks that develop from the same root system are genetically identical, so they look very similar from a distance. Some genetically identical groves can be quite broad, and include many trunks.
4. This small coastal redwood trunk is not happy about the fence that is nailed to it.
5. This is more what you expect coastal redwoods to look like. It is impossible to determine from this picture if these trunks are genetically identical secondary trees that emerged from the same root system, but their proximity to each other suggests that they likely are.
6. This epiphyllum is the flower that I promised to those who expressed a concern than my Six on Saturday lacked adequate bloom. I shared a picture of this same epiphyllum earlier, but it has continued to bloom.
This is the link for Six on Saturday, for anyone else who would like to participate:
There are so many big trees in the Santa Cruz Mountains that keep most of us looking up. It is easy to miss much of the understory plants that grow on the forest floor.
The flowers were not completely white. They were very pale hues of pink. The wood sorrel in the last picture was slightly more pinkish than the unidentified cruciferous (of the family Cruciferae) flowers of the first two pictures. Pale flowers, particularly those that seem to be adorned with barely perceptible patterns, are typically those that use infrared and ultraviolet color to attract pollinators that can see such color. If that was their intention, they would not look so bland to the pollinators whom they prefer to attract.
