Four years after chimeric albino redwood cones were discovered, Landscaper Lucas Dexter Vice President of Dexter Estate Landscapes came across another amazing redwood exhibiting the same variegated characteristics. Located in the in the heart of the wine growing region of Napa Valley, a planted Coast Redwood displays an aerial albino more stunning in appearance then the first discovery. With fanning branches in swirls of yellow and green, this mutation revealed something that few have ever seen. Tucked away behind these yellow branches were variegated albino and green chimeric cones.
In the pictures we see the three C's: 'clear characteristics of chimerism' by the well-defined albino/green boarder running through both sides of the right cone. What's intreaguing is how the boundaries between the genotypes do not follow the diamond shape pattern seen when the cones start to split open later in the fall. Seeds originating from these boarder sections may produce chimeric seedings. A joint effort is underway to collect the cones and attempt to propagate the seeds.
Another view of this beautiful aerial albino chimeric redwood.
Aside from this redwood discovery, Lucas has a passion for collecting rare Japanese Maples and has transformed his property into a small personal nursery. Each year Lucas adds to his collection & creates new plant introductions that he grafts himself. Most recently, he has been working with the International Oak Society to introduce a new selection of a Blue Oak that he found. Again, much thanks to Lucas for sharing this amazing find.
Featured in our 2019 news section, below are two incredible redwoods that are growing opposites.
In addition to albino redwood studies, there are numerous green mutations within Coast Redwoods that are noteworthy and deserving of further research & consideration. The trees within this category are truly a unique and testament to this amazing species. Like albino chimeras, some of these mutations listed below are so incredibly rare that only one tree example is known to exist. With the 2019 Save The Redwoods League Redwood Genome Project complete, hopefully scientists will be able to determine what causes these unusual mutations to exist and why. Below is a list of some of the strange and exceptional:
Approximately 100 miles separates two remarkable Coast Redwoods that seem to be polar opposites on the botanical scale. The first sports a massive burl at its base, while the second exhibits uncanny paper-thin bark unseen before within the species.
Ridgway Burl Giant:
Planted in Santa Rosa California around the time of the 1915 World’s Fair, the Ridgway Burl Giant most likely made its humble beginnings during the reconstruction period following the 1906 earthquake. Located within the Ridgway Historic District of the city, the tree sports the largest burl known for a Coast Redwood growing in the urban landscape. Bulbous in appearance like a giant onion, the tree’s burl was measured in 2019 at an impressive 11 feet in diameter. What’s remarkable is the tree quickly tapers down to a modest 3 ½ feet in diameter only 30 feet up from the base, thus giving the tree its unusual appearance. Above this point the tree tops out at a modest 117 feet in height.
According to the Ridgway Burl Giant’s owner, the redwood is approximately 105 years old. When calculating the wood expansion from the tree’s center within that time frame, the radial growth (all things assumed being equal) equated to 66 inches (167.6 cm) from the tree’s center. This equals an average of 5/8 inch (1.6 cm) of annual tree ring growth. This rate of wood accumulation is not uncommon for coast redwoods in a regenerative forest but exceptional for a tree growing in the urban environment.
As you can see from these pictures, the massive burl is taking over the yard in front of this quaint little cottage. One could assume that genetics are the reasons for this impressive growth or possibly an environmental factor may be lending to its unusual appearance. For now, the mystery remains for this stately tree on Ridgway Avenue.
Grey Bark Redwood:
For our next tree you may want to put aside any previous thoughts of what a Coast Redwood is supposed to look like. Unlike the Ridgway Burl Giant, this tree heads in the opposite direction when it comes to amazing growth. Instead of living up to the species reputation for size & height, this redwood has remained incredibly small. If scientists could cross a Sitka Spruce with a Coast Redwood this tree might be the odd result.
Known simply as the Grey Bark Redwood by Sacramento area arborists, this dwarf Coast Redwood is the sole representative known within the species. Standing approximately 32 feet in height exhibiting a weeping top, this tree’s features are so unusual that it would be easy to misidentify even by an expert. The redwood’s bark is the most striking attribute when first approached. It’s incredibly thin and smooth in appearance, exhibiting strange whirls and checkered like patterns. This uncharacteristic look is in contrast to normal Coast Redwoods that exibit stringy, soft, &, verticality aligned ridges within their bark. It’s only after a closer inspection of the tree’s foliage that one can tell is truly a Coast Redwood by the alternate needle arrangement. For those of you wondering if this could be a Dawn Redwood, that species exhibits an opposite needle arrangement and is deciduous unlike their coastal cousins.
According to historical records, the Gray Bark Redwood was planted around 1965 and is approximately 54 years old as of this writing (2019). Within that time frame the tree has grown just a mere 11.5 inches in diameter. This is far below what would be considered average for a tree living for more than five decades. When calculating the average growth from the tree’s center within that time frame, the radial expansion (all things assumed being equal) equated to just 5.75 inches (14.6 cm) of growth from the tree’s center. This equaled just 53/500 of an inch (2.70 mm) of annual ring growth. To put this in perspective, the wood accumulation on this tree is so slow that each year the tree’s rings add the thickness equivalent of just two dimes. With that said, the wood is assumed to be incredibly dense.
Some of the reasons proposed for the tree’s unusual growth is a combination of genetics and the tree’s environment. There’s a possibility that a nutrient deficiency may be at play in its unusual growth. For now, this small coast redwood is another example of how amazing and versatile the Sequoia sempervirens tree species is.
Brad Buttram is an autodidactic tree enthusiast born and raised in northwest Oregon where he resides with his wife and kids. Brad's love and fascination for trees started as a child being in awe of the giant sequoias planted in and around Forest Grove and Hillsboro, Oregon. His fascination for trees grew after he discovered an ancient Oak tree in Washington state that he named ‘Goliath’ when he was only 6 years old. In October 2018 Brad was put in contact with Chimera Redwoods by Crowfoot Nursery after discovering the largest periclinal Grand Chimera known in Oregon. Since that discovery, he has been on a hunt for these strange mutations on planted redwoods throughout the state. Brad has discovered multiple albino redwood sites, including the first NCV known in Oregon. Aside from searching for albino redwoods, Brad is also collecting data on the naturalization of the redwood species in northern Oregon as it relates to climate change.
Dave Kudy a docent at Henry Cowell Redwood State Park shares with us a refreshing video about albino redwoods. He explains that these unique trees are one of nature’s treasures in the forest. As the protector of albino redwoods, Dave hopes to balance the public’s curiosity with protecting these trees into the future.
Redwood enthusiasts who are lucky enough to know where these elusive albino redwoods reside have discovered that some of these peculiar trees tend to dieback and regrow in cyclical patterns. Some basal albino redwoods exhibit large amounts of leaf litter accumulation while others show very little accumulation. As if the albino redwood mystery wasn’t complex enough, some experts have suggested that this dieback & regrowth pattern occurs because the mutations are easily prone to environmental stresses. Specifically: heat, cold, and drought conditions appear to play a role in albino redwood mortality. Research at UC Santa Cruz has shown that albino redwoods do indeed transpire at much higher rates in summer compared to their green counterparts as seen here in this paper: The water relations and xylem attributes of albino redwood shoots These discoveries have led experts to speculate that albino redwoods overall may have inefficient stomatal control leading to excessive moisture loss and death within their needles. Stomata are pores on plant leaves that help regulate transpiration and water loss. In normal green redwoods, cool humid conditions will prompt stomata pores to open allowing for a greater surface area for transpiration to occur. Conversely in warm weather accompanied by low humidity, stomata will close down to conserve water. The situation for albino redwoods is more problematic and appears to run counter to the normal function of the plant. In hot weather, if albino redwood stomatal cells don’t closedown enough to limit moisture loss, the foliage will cavitate, wilt, and die. On the other hand, if temperature and humidity levels are ideal, but there isn’t a sufficient amount of sugars readily available from the parent tree, the mutation will dieback due to deprivation. This is a catch 22 situation that albino redwoods must face on a daily basis. Even when surviving in this precarious state, it’s not known if reliance on high transpiration rates is definitive reason why there’s a tendency to see dieback on these trees. While it’s generally understood that all redwoods (whether albino or not) will experience some form of die back under extreme moisture stress, it’s not known if the parent redwood is sacrificing the mutation at the expense of water or energy conservation.
Additionally, other seasonal factors like excessive heat, & freezing temperatures have led to further assumptions that albino redwoods may not have adequate coping mechanisms for extreme weather conditions.
Pictures of a basal albino redwood in the natural range. The photo on the left was taken in June 2012 while the one on the right was taken June 2018. Notice how the albino redwood almost appears dead in 2012, only to return to a more vigorous state in 2018. Some may attribute this to the drought that was experienced between 2011-2016. If this is true, why do surrounding green shoots appear unaffected in both the 2012 & 2018 pictures?
If these reasons aren’t enough to show albino redwoods are at a real disadvantage, other factors such as fungal pathogens, insect damage, vandalism, and animal browsing can further add to the demise of these trees. Sudden oak death which has made headlines in the last couple decades produces minor dieback on both green and white foliage. Various insects such as thrips and mites which are common in redwood forests attack redwood needles and discolor foliage. Vistors at times take albino foliage as souvenirs also adding to further losses. Deer which have been known at times to rub their antlers on young trees during the fall rut also contribute to additional damage. The culmination of these external causes doesn’t appear to add up to a cyclical pattern of dieback seen in albino redwoods, but can further contribute to their destruction.
With the culmination of the above, albino redwoods are indeed in a precarious position and must find a balance to survive. These disadvantages alone, make researchers question how these anomalies of nature can survive in an environment where the deck seems stacked against them. But are albino redwoods truly fragile mutations or robust warriors? Some may indeed exhibit poor stomatal control, but are they really at the mercy of the weather or is there another factor at play pointing to albino redwood mortality? What advantages do healthy appearing albino redwoods have over their counterparts and what can their life cycles tell us about the overall health of the redwood forests? These questions may seem daunting as if one was to begin tackling a 10,000-piece jigsaw puzzle. It seems current research is only now starting to place together the outer edges of the mystery.
Cotati Tree Chimeric Albino redwood illustrating various mosaic patterns seen within these mutations.
In order to start putting the pieces into place, several key questions needed to be asked and formed into a hypothesis.
Are albino redwoods fragile due physiological, ecological, or environmental causes?
A) Are climate factors contributing to albino redwood dieback or longevity?
B) Does temperature variation effect stomatal control?
C) Can albino redwoods endure weather extremes?
D) What implications will these results have on the species?
Because naturally occurring albino redwoods in the wild are very rare, studying a various group of trees in the natural setting was deemed impractical for logistical & ecological reasons. The concern was to conduct a study which would yield the best possible answers, yet not leave the human footprint within the forest. In order to achieve this, a group of 25 propagated chimeric albino redwoods were selected & planted a test plot within the Central Sierra spring of 2017. Ten trees were initially planted in the ground with the remaining planted out over the course of summer. Trees selected for the study exhibited traits that were morphologically very similar to albino redwoods in the wild and ranged from 3-8’ in height. Both the wild & planted albino redwoods exhibit sectors that had mutated foliage supported by healthy green foliage. Observing the growth patterns with propagated albino chimeric redwoods allowed researchers the opportunity to see daily changes in a controlled setting that otherwise wouldn’t be possible with albino redwoods in the wild. Various chimeric albino redwoods from different parts of the natural range were selected for the study to gain a wider genetic sampling on how these chlorophyll deficient mutations would respond.
Seven-foot-tall chimeric albino redwood at the Sierra test site.
The location chosen for the test plot was well removed from the native range of Coast Redwoods by more than 100 miles. The site was situated in a lower montane forest at an elevation of approximately 3500’ elevation. The test plot’s climate fell within USDA hardiness zone 9a which exhibits average winter low temps between 20 to 25°F. At this elevation, snow is frequent in winter adding additional element of stress to the trees that otherwise would not be seen regularly in the natural range. Summers exhibit hot conditions with temperatures frequently running from the low 90’s to the low 100’s°F. Additionally, humidity ranged only between 13-60% during the summer months. Some might consider this a hostile environment well beyond the scope of what would be seen in the natural setting. Because of these climate extremes, all trees were given supplemental irrigation during the summer months so as not to induce water stress. The experiment was looking for stomata control in relation to heat & cold tolerance in albino redwoods & not the test subjects’ ability to withstand drought stress.
During the summer of 2017, all subjects were exposed to temperatures of over 100°F. Daily temperature fluctuations averaged between 68-93°F per day and did not exceed a temperature swing more than 30°F in a single day. By late fall of that year, remarkably only 5% of the albino foliage from the 2017 growth season exhibited some form of dieback. A modest 20% of dieback occurred on albino foliage that was two seasons or older.
Tree #14 originating from Santa Cruz County endures the full afternoon sun on July 29th 2017. A nearby weather station recorded the daily high temperature at 98°F . Note how a majority of the albino foliage appears healthy despite the intense heat. The all-time high for the year was recorded a month later on August 28th, 2017 at 104°F.
Picture taken after the trees were planted on Nov 3rd, 2017. Notice how little albino foliage has died back on tree #14 during the summer months despite days of temperatures over 100°F.
As winter approached, it was not known if the albino foliage would be as resilient to cold weather as it had with coping in the summer heat. February daily winter temperatures averaged between 55°F -35°F per day with humidity ranging between 35% & 85%. As with the summer results, the albino foliage on 90% of the test subjects exhibited cold tolerant characteristics unseen before in albino redwoods.
In the dead of winter, albino foliage appears mangy on Tree #14 but is otherwise healthy under the snow. Picture taken February 21st, 2018. Two days later on the 23rd the lowest temperature of the year was recorded at 18.7°F.
Tree #8 originating from Sonoma County shows the contrast of albino & green foliage in the snow. At times, these trees were covered in over a foot of snow during the winter 2017/2018. Picture taken February 18th 2018.
The following spring, albino foliage on tree #14 survived remarkably well over winter with minimal dieback. Picture taken in April 1st, 2018.
Close up of tree #14 in April 2018 showing foliage in excellent condition after enduring winter snow and ice. Picture taken in April 1st, 2018.
A closeup of Tree #8 April 2018 exhibiting albino redwood foliage after surviving the winter of 2017 & 2018. Like tree #14, albino foliage shows almost no dieback after winter.
By spring of 2018, only 10% of year old albino foliage exhibited some form of dieback from either heat or cold stresses on all test subjects. A more modest 30% dieback occurred on albino foliage that was at least two seasons or older.
If the weather environment at the Sierra test pot site exhibited temperature extremes higher and lower than what’s normally seen in the natural range, then why did these test subjects perform remarkably well during the heat of summer and cold of winter compared to their wild counterparts? One would assume that more needle dieback on the Sierra test subjects should have been seen compared to the natural occurring albino redwoods along the coast. Another could argue that the test plot trees were given ample irrigation compared to the albino redwoods in the natural range which relies solely on fog drip and ground water. If this truly was an unfair advantage, then why does normal green foliage on the parent trees to albino redwoods appear healthy when albino foliage started to dieback? The answer appears to indicate that redwoods may not exclusively be dependent on how much water is readily available, but how they respond & adapt to rapidly changing weather patterns.
To test the hypothesis that rapidly changing weather patterns is influencing albino redwood dieback, a comparison was made between the weather patterns at the Sierra test plot site to two locations within the natural redwood range. Specifically, the weather patterns at Guerneville in Sonoma County and Felton in Santa Cruz County were used in the study. The hottest three consecutive days in July 2017 were plotted and compared at all three sites.
Data curtesy of Weather Underground.
What's remarkable was the huge 24-hour variation in temperature and humidity reported by the Guerneville and Felton weather stations compared to the Sierra site. The trees within the Sierra test plot rarely experienced temperature shifts greater than 30°F per day and humidity changes of 33%. In contrast, the Guerneville and Felton sites exibited temperature shifts greater than 51 degrees °F in a single day, accompanied by humidity swings exceeding 90% according to Weather Underground data. Cool on shore winds carrying low temperatures and high humidity during summer can quickly reverse to an off-shore weather pattern bringing low humidity and hot dry winds within a matter of hours. This yoyo weather effect induces stress on the native trees that otherwise would not be as pronounced in California’s interior. It’s plausible that in some individuals, the stomata within natural albino redwoods becomes overwhelmed in these conditions, leading to higher transpiration rates, cavitation, and eventual dieback. In comparison, the relatively dry Sierra Nevada test site provided a more stable temperature and humidity environment allowing for more efficient stomatal control in coast redwood albino chimeras.
A second temperature & humidity comparison was made for winter 2018 between the Sierra test plot site and the Guerneville & Felton locations. The coldest three consecutive days in February were plotted and compared at all three sites.
Data curtesy of Weather Underground.
The winter trend lines for temperature and humidity appeared to follow a little more closely between all three sites compared to summer. Temperature fluctuations were less severe averaging a modest 32 degree °F swing at the Sierra site, 20 degree °F swing at Guerneville, & 21-degree °F swing at Felton. As expected, the Sierra site exhibited lower temperatures and humidity levels compared to the coastal locations. The humidity results showed a reversal in winter between the Sierra and coastal locations. The Sierra site showed the largest humidity swing of approximately 71% when compared to Guerneville’s 64%, & Felton’s 58% respectively. It’s speculated that the winter dormancy period combined with a lower variation of temperature and humidity may help preserve albino redwood foliage.
Stepping back and looking at the history of the Felton and Guerneville sites before the old growth forests were removed; temperature and humidity changes most likely were more moderate during times of hot and cold weather periods compared to today. The dense stands of trees acted as a temperature and humidity buffer when rapidly changing weather patterns descended upon the forests. Because of these insulating properties, the trees created their own protective weather bubble by limiting moisture loss which is not seen at these sites today. Without the support of large tree stands, it’s assumed that the genetics of these individuals may not be as adaptive or tolerant to rapidly changing weather conditions as redwoods growing in more interior locations. Field observations have shown that albino redwoods growing in the natural range which exhibit fewer signs of cyclical dieback are most likely to be found growing in isolated interior groves. These trees are far more likely to be subject to weather extremes than their coastal brothers. These redwoods exhibit better stomatal control than trees near the coast & may be better adapted to coping with rapidly changing weather environments. In the broader sense, these implications may have a larger impact for the redwoods species as scientists delve into the questions of climate change. The answer may not lie with redwoods just adapting to new climates, but one that offers adequate moisture and a minimal shift in daily temperature & humidly variations. Redwood trees that can withstand large temperature and humidity shifts may be better suited to planting in new environments.
The Amador Sentinel growing high above the banks of the Mokelumne River & Highway 49 is a normal green coast redwood located in the Sierra foothills. The tree is situated on a dry south facing slope surrounded by grasslands. How this tree survives hot scorching summers may be in its ability to conserve water through strong stomatal control and adaptation to an environment that favors lower variation in temperature & humidity.
Can you spot the redwoods growing in this picture? Believe it or not, these coast redwoods are thriving amongst Ponderosa, Gray, & Knob Cone Pines which are species specifically adapted to drier environments. The trees are growing in an isolated interior grove within Pope Valley in Napa County. These redwoods endure colder winters, hotter summers, and drier conditions compared to trees near the coast. What’s remarkable is these redwoods have adapted to survive in this difficult environment.
In conclusion, the foliage in albino redwoods has shown remarkable resiliency to survive the harsh weather extremes of the Sierra Nevada Mountains. The results were quite astonishing for a mutation that once was considered quite fragile. This study demonstrated that albino redwood foliage does have adequate stomata control within a certain temperature & humidity band. It also shows that albino foliage does have the ability to adapt to weather extremes so long as the changes are gradual. Looking at the species as a whole, the key to redwood endurance may not hinge on a gradually warming climate, but an environment that lends itself to where trees can readily adjust to rapidly changing weather conditions. Whether the climate is hot or cold, it appears an environment which offers a lower variation of temperature & humidity may favor long term survival for coast redwoods. The implications of these results may lend to normal green redwoods being genetically selected for more efficient water conservation qualities. This in turn could lead to trees that are better adapted to shifting weather patterns and drier conditions as the species faces the challenges of climate change. Individuals that exhibit robust stomatal control may be key in preserving the species into the new millennium.
Do you want to learn more about albino redwoods & see these fascinating trees up close? This Labor Day weekend fellow Albino Redwood Researcher and Arborist Tom Stapleton will once again return to Humboldt Redwoods State Park to host two special events:
Interpretive Walk September 1st, 11 am:
Come join us on a park sanctioned walk to see some of the most unique albino redwoods within the park. On this outing, you'll have the chance to learn about these mysterious trees and see the fascinating aspects how they differ from normal green redwoods. This will be a rare opportunity to see albino redwoods which are normally not disclosed by park personnel. The highlight of the walk will be the chance to see the largest aerial albino redwood known. The gathering location will be at the HRSP Visitor Center. From there we'll caravan a few miles away to an undisclosed location within the park to see the trees. Be sure to bring your camera! Duration is approximately 90 minutes, difficulty is easy, & admission is free!
Campfire Talk September 1st, 8:30 pm:
Later that evening, Tom will put on a slide show presentation about albino & chimeric redwoods to park visitors and guests. Here we'll learn that redwoods are not only famous for their size and height, but also for their mutational colors. The talk will consist of the history of albino redwoods, the various types found, & the latest cutting-edge research. This will be an opportune time to see live chimeric albino redwoods on display. The campfire talk will be held next to the HRSP Visitor Center. Duration 50 minutes & admission is free.
Hope to see you there!