Lots around here (SF Bay Area). I even have one that I grew from seed.

Sara...any chance that you could post a pic of yours? Would love to see it!

Bay Area is probably one of the more ideal locations here for this tree :-)

That's interesting to me, gg, as these pics were taken in Thimphu, at an altitude of around 2300 metres (7000+ ft), with bitterly cold winters, and I didn't see them growing naturally at much lower altitudes...

Shaxhome mine is only about 5-6' tall and hasn't bloomed yet. I grew it from seed which germinated in 2007. There are many specimens at Quarryhill Botanical Garden nearby here, I just checked their website but only have photos of the fruit. What I like about this tree is that it is just as showy in autumn as it is in spring.

Often plants with a Himalayan origin have other limitations over and above cold hardiness. I have a feeling mild summers come into play as well. Generally, this dogwood is shown as being limited to zones 8&9 here in the US. But as is often the case with many less common plants, perhaps its true winter hardiness has not been fully tested.

Just checked the weather for Thimphu and it is hovering just about where we are right now in the Puget Sound area, so maybe not quite as bitterly cold as you think. Or as bitterly cold as compared to just about anywhere in Oz :-)

Ha! Yes, considerably colder than I'm used to in Oz. Winters there only around -5C (23F), but it wouldn't get above 0C (32F) for sometimes weeks on end. And the Bhutanese are hardy folk and quite blase when it comes to heating. I had to wear snow gear inside restaurants on occasion! And I do remember one -18C (0F) night when my plastic bucket of bathwater on the kitchen table froze solid overnight.

"Five species: from the Himalayas to E Asia; five species (two endemic) in China.

Species delimitation within this subgenus is controversial. Over 15 new taxa have been published since the 1950s. This treatment follows Xiang (Bull. Bot. Res., Harbin 7(2): 33–52. 1987), who recognized 13 subspecies among four species, i.e., Cornus capitata, C. hongkongensis, C. kousa, and C. multinervosa. However, a preliminary allozyme investigation by Dudley and Santamour (Phytologia 77: 425–430. 1995) suggested that C. capitata subsp. capitata is quite divergent from C. capitata subsp. angustata. Thus, in the present treatment, we recognize C. elliptica as a species separate from C. capitata. Further studies are needed to test the various species delimitations in the group."

http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=316356

"Plant of the Month: June 2004"

http://www.arthurleej.com/p-o-m-June04.html

I often see trees similar to those here in Canada!

I often see trees similar to those here in Canada!

Yes: type shown resembles C. kousa in these shots.

Wow. Those blossoms are incredible.

Those blossoms are incredible

Whatever exact species placement of example shown it looks mostly like a typical C. kousa - including the floral effect. However getting one of these to persist outdoors in USDA 4 might be a problem. Also soils and summer climate in WY might be excluding, except perhaps up where the conifer forests are in the mountains (moister and more likely to be acidic than in the lower, less steep areas where people concentrate). This may be why the tree is unfamiliar. Where conditions are generally suitable it is much planted.