Mark McCaughrean

Who knew? 😳

While there are only 80,000 of those iconic giant redwoods left in their native California (I blame all those rubbish speedbike riders in Return of the Jedi), there are 500,000 now growing in the UK.

Smaller so far, given that they’re much younger, but apparently the warm wet weather conditions suit them well & the largest are already over 50 metres tall.

Story & pix by my lovely friends Becky Morelle, Ali Francis, & Tony Jolliffe at the BBC: https://www.bbc.com/news/science-environment-68518623

Giant redwoods: World’s largest trees 'thriving in UK'

A survey of giant redwoods growing in the UK reveals the trees are doing well - and growing fast.

Mar 13, 2024 at 9:25amIceCubesApp
Show threadFrank Bennett 🇯🇵Mar 13, 2024
@markmccaughrean So good to hear!
Show threadksircombeMar 13, 2024

@markmccaughrean Looks like they are doing much better than the surviving redwoods that were planted in Canberra 100 years ago against all advice (basically Canberra is fairly dry, 500 mm a year about a quarter of what a redwood tree really needs).

I pass the forest frequently and always feel sorry for them. They have recovered a bit since this video in 2020 - somehow they hang on!

https://www.gardenhistorysociety.org.au/publications/pialligo-redwood-forest/

Show threadPauline von HellermannMar 13, 2024
@markmccaughrean I listened to that this morning - so interesting to hear! One of those 500,000 #giantredwoods is at New Cross Gate station in London, olanrd by a rail worker a few years ago. Hope it will continue to thrive!
Show threadJonathan HendryMar 13, 2024

@pvonhellermannn @markmccaughrean

It better thrive or it's going to make a mess of that station when it falls, never mind any rains passing at the time.

Show threadPaul MartinMar 13, 2024
@markmccaughrean Sadly it appears they cannot reproduce here.
Show threadMark McCaughreanMar 13, 2024
@nowster Yes, I spotted that part of the story & it surprised me. Can they be “helped” to reproduce locally or have all 500,000 trees been grown from imported fertilised seeds?
Show thread@richh has movedMar 13, 2024
@markmccaughrean @nowster IIRC, part of their lifecycle is forest fires opening up the seed pods. Something many Botanic Gardens are unwilling to replicate for some reason! 🤷‍♂️ I assume individual specimens in parks and gardens would also have difficulty getting fertilised, so require artificial propagation.
Show thread@richh has movedMar 13, 2024
@markmccaughrean @nowster On the wildfire front, I believe this realisation is one reason US National Parks are doing more prescribed burns - burns are important for controlling wildfires (clearing out understory), but also no new sequoia were germinating when they had their policy of just trying to suppress fires - turns out that was why. They were interrupting the reproductive cycle.
Show thread@richh has movedMar 13, 2024
@markmccaughrean @nowster Should also note on “helping”, 500k non-natives is a healthy population to be going on with. We have critically-endangered species like Black Poplar which need immediate help. Just a few hundred left in the UK (often isolated with no neighbours to pollinate with). Not to diss sequoia because they’re incredible. But reinstating Celtic rainforest and other native woodlands/habitats needs to be the main priority for preserving biodiversity.
Show threadLaura LangdonMar 24, 2024

@richh @markmccaughrean @nowster Exactly this! Our redwoods reproduce best after fires and floods, so they don’t do well in areas where humans prevent these things. But they reproduce asexually, so they don’t need friends, just Extremely Dramatic Weather.

Real-life phoenixes, our redwoods!

Show threadInsertUserMar 13, 2024

@nowster @markmccaughrean

Annoyingly, I can't seem to find anything online saying why not.

Show threadPermacultureandpoliticsMar 13, 2024
@markmccaughrean you can buy redwood seedlings from Burnt Ridge nursery in Washington. Anyone who lives in PNW and has an area unlikely to be developed should consider planting them. California redwoods are likely to burn up if humans don’t get very serious about #ClimateChange and #wildfires so let’s plant these magnificent trees wherever they will thrive, for future generations.
Show threadxs4me2Mar 13, 2024

@markmccaughrean

Great!

Show threadRachel GreenhamMar 13, 2024
@markmccaughrean @lisamelton wonder if they'll also stay smaller no matter how long they live, because they're not getting all that salmony protein goodness they get in the PNW… (though not sure the salmon thing applies in California)
Show threadMatt GoddenMar 13, 2024
@markmccaughrean There’s a colony of them in Australia, Victoria near the 12 apostles, if I recall correctly.
Show threadTree of LifeMar 13, 2024
@markmccaughrean Yay. Got one in my garden. A young coast redwood. Bought it online as a titchy thing - now 25 feet tall.
Show threadÓscar Morales VivóMar 13, 2024

@markmccaughrean I honestly don’t know where that 80k number comes from. Maybe at the nadir of the logging era? Or are they mixing up redwoods and sequoias? (The latter only grow in the Sierra and are a lot more threatened but it’s not the ones that are thriving on the UK).

I have probably walked past more than 80k redwoods myself. A lot of their logged range just sprouted again once left alone and is thriving. They survive fires better than anything else in the forest and grow in an area that isn’t very affected by climate change so far since the nearby ocean keeps things more stable than elsewhere.

It’s pretty cool that there’s a bunch of them in the UK though. I wonder if they’d grow well in Galicia and northern Portugal.

Show threadSamhain NightMar 13, 2024
@MyLittleMetroid @markmccaughrean Yeah, I was going to say that number sounded a little off. Do they mean redwoods, Giant Sequoias or just regular sequoias, because Costco is selling 10ft sequoia saplings right now.
Show threadMark McCaughreanMar 13, 2024
@MyLittleMetroid @markmccaughrean The article talks specifically about giant redwoods / sequoia (Sequoiadendron giganteum), but the linked Royal Society paper says that the UK number of 500,000 trees also includes coastal redwoods (Sequoia sempervirens). How many of the latter there are in California & the PNW, I can’t immediately find, but perhaps many more.
Show threadMark PauleyMar 13, 2024
@markmccaughrean good luck getting rid of them. In Santa Cruz, they are famous for pushing up shoots through several feet of asphalt parking lots a few years after being clear cut. They are like California bamboo
Show threadKetumbraMar 13, 2024
@markmccaughrean Brexit benefit? /Sarcasm
Show threadBrownsBayMar 13, 2024
@markmccaughrean I remember spotting one while on a walk in the Cotswolds. Our walking guide didn't believe me. These trees are a common landscape tree in the Seattle area, easily recognized by their form and solid trunk mass.
Show threadglasspshrMar 13, 2024
@markmccaughrean well hey I'm taking care of the two I have in my yard here in California, but good to hear
Show threadCosvakMar 13, 2024

@markmccaughrean idea for a movie. Remake of Robinhood set in a post apocalypse future where most of great Britain is a giant endor style redwoods.

Interject aliens if it works

Show threadFionaMar 13, 2024
@markmccaughrean Pesky speederbikers...but the Ents of America had enough I guess and emigrated to the UK, good for them
Show threadarceuthobiumMar 13, 2024
@markmccaughrean the Endor scenes starred coast redwoods, not giant sequoias.
Show threadMartin SeegerMar 13, 2024
@markmccaughrean Not only there. I know of specimen in northern Germany.
Show threadAllie PottsMar 13, 2024
@markmccaughrean a few are growing in North Carolina too. https://www.wral.com/story/hidden-in-plain-sight-huge-redwoods-grow-in-raleigh-wilson-chapel-hill/19195428/. It’s a fun game of, “is that what I think it is?”
Hidden in plain sight: Huge redwoods grow in Raleigh, Wilson, Chapel Hill

In the Redwood Forest in California, the trees are so tall they block the sun, forcing drivers to use their headlights even at noon. The trees are so thick that cars can drive right through the middle of some Redwood trunks. Many people have no idea that these giant trees also grow right here in the Triangle.

WRAL