It's common for many cypresses to discolor during the colder months. Last winter I had two Sequoia sempervirens survive 11F while in pots! They also showed discoloration just the potted Giant Sequoia, a few feet away, did.

The foliage starts to get a bit browned at about -15°C, with significant dieback below about -20°C and killed outright below about -25°C. The actual figures can vary a bit depending on other factors such as relative humidity (low humidity increases desiccation burn), wind speed (strong cold winds burn worse), and duration of the cold (a long cold spell is worse than a short snap).

"I go by celsius"
Very wise, it's the only sensible way to measure temperature ;-)
(unless you're a physicist dealing in Kelvins!)

Resin

Large, long-established trees singed in Seattle by winter producing readings ranging from 2-12F in different parts of town.

95' (29 meter) large, 45 year old trees visibly unaffected by 0F in Williamsburg, VA.

There is a large tree at the Scott Arboretum (Swarthmore, PA outside Philadelphia) that must have seen at least -20C and probably lower at some point. Unfortunately, Camellia Forest lost their source plant derived from it to this summer's drought, so they will not be offering the hardy clone again any time soon. Of course, the Arboretum can't bother to offer this during their fundraiser sale, focusing on the more important plants like Echinacea 'Razzmatazz'. Oh year. F--- yeah.

Any fossil record for sequoia outside North America just interested

Resin

Do you know of any sequoia fossils outside North America
was Sequoia in Asia? Europe? im very interested.

Difficult to say, depending on whether fossils are true Sequoia or belong to related (but now-extinct) genera. Fossils resembling Sequoia include Sequoia abietina (Europe), Austrosequoia (Australia: Q'land, Tas), Yezosequoia from Japan, Drumhellera, Yubaristrobus (Japan), Quasisequoia (Sweden, central Europe), Peltaconus (Greenland). More dubious fossils include Geinitzia Araucarites, etc.

Resin

Hi Resin

Thats very interesting I think many conifers couldn't
complete against the flowering plants and climate change
was also another factor.However many genera like Wollemia
found a niche so maybe Austrosequoia could have found
a niche in Australia or Tasmania.

The fossils of Austrosequoia are mid/late Cretaceous, about 95 m.y. ago, so not much chance of it still being around. Some suggestion that it may be allied to an ancestor of Athrotaxis, though.

Resin

Wollemia nobilis is 200 years old so it just shows that
some species can find niches and survive up to the present
day.

200 years is a lot less than 95 million years . . . about 500,000 times less ;-))

Presume you meant 200 million . . . but the fossils that age which some have associated with Wollemia don't show all that much similarity to it. They could be almost anything, and likely are not allied to Wollemia. Hype to help sell the plant, not real scientific evidence.

Resin

Resin,
you seem highly knowledgable how on earth do you retain all that info; i find it difficult to keep track of genus species names; is there a trick to it?

He's a natural.

The tricks to life conecollector:
Write: Rewrite: Write again.
Read: ReRead: Read again.

It isn't magic man. His brain is hotwired. Like an athlete. Althought he contends to have quite a lot of resources.

You'll get old and wise someday. Some learn a little quicker but he's still a natural, it's in his genes. I've been on this forum since late 2001 and I still don't know much about him other than that he knows where "Methusolah" (The ancient Bristlecone Pine) is and that he lives in England, and that He writes descriptions for conifers on webpages; He lives in England. He's on the board of "people" who decide and vote on the names of conifers, i.e. The discovery of the new Vietnamese Cypress. And he's mentioned that he "reads." Now Idea how old you are Resin. Unimportant always!

Dax

He also travels to parts of the world to learn hands on!
Can't forget that boss! lol

Dax

"you seem highly knowledgable how on earth do you retain all that info; i find it difficult to keep track of genus species names; is there a trick to it?"

Things called 'books' . . . still worth investing in, even in this internet age ;-)

Yes: part of knowing what to do is knowing where to look, when you need to. Even a professor has a wall of books in his office. I've been criticized recently for quoting from books here. That I do that doesn't mean I've been looking everything I post up. There are multiple reasons for excerpting from outside sources, as part of a discussion. That's why there's an Optional Link URL box provided by the site.

Another idea that has popped up more than once in discussions on this site is that if it's in a book it's invalid, the flip side implication being that if someone types it off here or better yet says it to your face it's automatically more valid. No, books are just another format for information. They can reproduce baloney or be worth their weight in gold. They do have the advantage of being edited (with varying degrees of success). The only "peer review" or "editing" that occurs here is follow-up posting.

Yep! And the better the professor, the larger the bookshelves in his (or her!!) office is likely to be . .

Resin