That is so weird, because they only seem to do better with age here 😕 I have seen small ones die from cold but larger ones do much better.
I have seen bigger ones die because they become so good at taking water in that they rot in the winter. This is becuase of bad drainage, they have a root system that spreads and is very good at taking water in. When they are young they can handle more water, and need more water.
Normaly Yucca Brevifolia should have no problem if a larger specimen in -23C I have seen one for many years in Pocatello Idaho take down to -20F maybe even -25F back in the 1980's. But it was a larger one and had excellent drainage.
There is also some very large ones in Saltlake City Utah that have seen close to -20F in the eighties that are still there. I think it has to do with the wet more than cold?

I have a couple of tree ferns in my garden. My largest specimen I planted in 1994 has over 4'ft of thick trunk and 8'ft fronds. It is rare that they ever turn brown from cold. I have only seen that happen once since I planted it. They are as lush as can be right now and by late March 2 dozen new ones will start to unfurl. I have smaller tree fern as well and it is also nice and green. In colder climates it would be good to protect the fronds if you want to keep them green overwinter. Cheers, Joe

I have a couple of tree ferns in my garden. My largest specimen I planted in 1994 has over 4'ft of thick trunk and 8'ft fronds. It is rare that they ever turn brown from cold. I have only seen that happen once since I planted it. They are as lush as can be right now and by late March 2 dozen new ones will start to unfurl. I have smaller tree fern as well and it is also nice and green. In colder climates it would be good to protect the fronds if you want to keep them green overwinter. Cheers, Joe

Your right it is a wet cold that killed it. It was covered in ice.

Joe do you have pics of your tree ferns 🙂

Hey Desertdave,

I've never heard of Live Oaks sprouting up from the roots after a killer winter, but it might be possible. What they do want is a mild, moist winter with a hot, dry summer. The Ponderosa Pine is, of course, a beautiful tree with many benefits. It does, however, drip sap. A killer sap that will kill anything underneath it for obvious reasons. They are a beautiful tree though. As for "squirrel attacks"-- I don't know what that is. Are you saying that you have killer squirrels in you area? What do they do?

Yah I have killer squirrels. They used to dig up my oaks to pluck the acorns off of them, but once I started removing the spent acorn when the seedling had grown a bit, now they seem to attack everything I grow from seed, often by cutting them down. Maybe they snap them by trying to climb them? Dunno, don't care... I will buy replacements. I may booby trap my seedling beds as well, with rat traps...

The squirrel is what killed that oak tree; it had apparently survived the two cold blasts. Did not quite look as robust as the other one I have, but still pretty sturdy. I have read somewhere that Q. chrysolepis is anecdotally hardy to zone 5; if that is so, a Dec. 1990-style Arctic blast might get them, but that is one reason I am trying to grow them, to see if they will grow here or not.

chalk a couple more up for the dead 🙁

1-Echinocereus engelmannii

2-Echinocereus Coccineus, not all of them but some I had for a few years now 🙁 They were looking good also 🙁