In '08 I had planted a 3 ft specimen of Tsuga canadensis in a somewhat protected location, it had wintered with very little damage. This gave me hope and I planted yet another one, this time in a much more protected site. Unfortunately, last winter they were both hard hit and pretty much lost all growth above the snowline, so this was a disappointment with these lovely trees.

Terry

Over the years, I've seen a few dwarf weeping hemlocks in the area, the largest being about 4 ft ... though, none of these had been looking too terribly thrifty.

I know that with Austrian pine there is a lot of variation in cold hardiness. So much so that some sources say zone 5, some zone 3. I have 200 2 year olds now. 1/3 of them are dead or sad looking, 1/3 ok. and 1/3 lush and growing well.

Douglas fir has two recognized types: coastal and interior. And one suppler also carries eastern slopes doug fir.

Some taxonomists recognize interior alpine fir as a separate species. And I read a paper that the latitude/altitude of the source affects spring frost tolerance. Northern ones tend to break bud early to take greatest advantage of short summers, while more southern ones live in a habitat that has more chaotic spring weather, and so are a bit more cautious.

So the key is going to be to find a batch to try that come from a cold dry climate.

Hmm.

There are a few native outposts of Tsuga canadensis growing in zone 3 Minnesota. I have wondered if their genetics would really be different from the northwestern species front in Wisconsin, and have conclude that the probability is low. This, mainly because the species has only been within reach of Minnesota for only a thousand years or so, hardly long enough for differentiation to occur. Still, a Wisconsin seed source is certainly better than one from Tennessee, Pennsylvania, or even Ontario. It's not only the cold temperature that is in consideration, but also the dry winter winds. I am not sure what Manitoba is like, but Minnesota is quite sunny in winter compared to more easterly states.

Northern ones [varieties] tend to break bud early to take greatest advantage of short summers, while more southern ones live in a habitat that has more chaotic spring weather, and so are a bit more cautious.

That is exactly right (in general). Kudos to you on your research! Likewise, seed dormancy broken by cold stratification is usually shorter for species native to extreme cold climates where soils freeze deeply.

Rick

Looking at the distibution maps, either the minnistota island, or just north Algonquin park along the Quebec Ontario border. I figure that I want seeds as far from the lake as possible to avoid lake effect winters.

Manitoba winters are sunny and cold, as are Alberta winters. Alberta isn't as cold.

This is often a problem: Sun and still airs make for warm pockets of air on the south side of the trees. Buds and needles dry out. Roots of course can't bring more water to replace the loses.

Couple that with LONNNGGGGGGG winters, and you have situations where trees that can take the cold can't take the dry.

I would tree T.c as an understory tree. Plant it into a grove of poplar, and try to convince customers to mix it with balsam fir when planting.

I grew up in the Kapuskasing area of Ontario and we had Hemlock growing up there. Was low growing but must be hardy as it gets down to -40 or lower in the winter. These grew wild not in yards.

Interesting. That's way north of the boundary in the Silvics manual. I wonder if that manual has a bias toward, "commercially viable size" e.g. you have to be able to get a 2x4 stud out of it before your grandchildren go grey.

You said low growing. Would 'low' be consistent with freezing down to the snowline most years? I see this a lot near timberline with alpine fir. The bits that stick up, get sunburned, dehydrated, and, for all I know, eaten by mountain sheep.

How much snow does Kapuskasing get?

Mountain hemlock is nominally hardy to zone 3, but supposedly only grows where there is so much snow that the ground doesn't freeze.

I don't quite believe that. I have 40-50 survivors out of 250 planted in styroblocks. -- And last winter was tough, with the warm fall, then sudden cold, and freezing temps before any snowfall.

When I lived up there there used to be lots of snow and most of them were covered and growing in a the bush certainly protected. For sure you could not make 2x4's out of them. But maybe lots of tooth picks. Lots of lakes and muskeg up there so maybe the climate here might just be too dry. Do you ever plant into pots before outside as I have all kinds I'll take to the recycling depot if no one wants them

I go through about 3000 pots a year. Don't chuck them just yet. (I get landscape contractors to save them for me, and buy them for $100/pickup load.)

Am wondering if those so far north are atucually Taxus canadensis. Have you ever seen cones? Taxus canadensis like the moist boggy places. Tsuga canadensis, although will grow with high water tables, seem to prefer more solid ground in comparison, rather than the unstable, sponginess of bogs or ancient bog remnants, at least in Minnesota and Wisconsin.

Taxus canadensis grows in a sprawling nature, but with branches always upturned, rather than spreading, and has longer needles. (Branch leaders always turned up toward the sky.) Tsuga canadensis, if it is dwarfed or not, will have branches that will be growing horizontal in it's entirety. Tsuga canadensis has the tendency for leaders to not go straight up until wood has become a few years old. Then it straightens up. Taxus canadensis is just the opposite, growing straight up at first, but then sprawling and bending as it ages.

I wouldn't be surprised if there is Tsuga canadensis that far north, but they would be isolated outpost(s) and very uncommon.

Rick