I've been cruising the Smokies via Terraserver alot lately looking at aerial photos, and noticed that the upper part of McKee Branch looked promising for hemlocks. McKee is a branch running SSE to NNW, flowing into Caldwell Fork. It is one of a series of branches that drain into Caldwell Fork from the south side. The other branches that drain on that side in generally the same manner are Den, Palmer, Sag, Snake, McKee, Clontz, and Double Gap. The Park geology map shows that side of Caldwell Fork as being Thunderhead sandstone. 

They are mostly similar in many ways, dense hemlock stands in darker, wetter areas, with stands of open hardwoods pretty consistently showing up, white pines shooting up on the ridges above. They're all a little different as well, partly due to the fact that each is generally higher in overall elevation than the last. Palmer, Den, and Sag have more white pines down lower in the coves. Double Gap Branch, farther upstream, has I think comparatively the largest undisturbed northern hardwood type stand in the upper flats- NROs, sugar maples, and ash. To my knowledge, McKee and Clontz haven't been really looked at yet. Clontz shows up on disturbance maps as mostly undisturbed, but looks as though it has less hemlock than most of the others. I'm curious to see that one soon.

The lower flats of McKee were all farmed, but the upper reaches were left alone. There is a large flat area between the upper forks and along the west side that looked full of hemlock on the aerial photos, and they didn't lie. While the area was not mind-blowing or record-breaking, it was an impressive forest of many consistently large (10-14 feet circumference) 130-140 foot hemlocks, interspersed with a few moderately large and very old tuliptrees, with a smattering of birch, sugar maple, and buckeye all coming from a dense thicket of rhododendron. Abruptly, just on the east side of the east fork, the forest was practically devoid of hemlock and rhododendron, totally open with very old but not very big tulips, lots of cucumbertree, northern red oak, chestnut oak, bitternut and pignut hickory, sugar maple, a little blackgum, black birch, and more big downed chestnut corpses than I've seen anywhere in Cataloochee. The understory had a good bit of buffalo nut, mountain holly, and flame azaleas.

I did not explore the flats thoroughly by any means. I avoid dense rhodo solo backcountry bushwhacking, so I only went through the lower half of the flats between forks before taking the easy way out and heading out to the open side and traveling up a ways beside the flats. There is more territory, and worth checking out again- I might try to access it next time from Cataloochee Divide above to get in faster. I got fairly accurate heights on a few, but I could not see the bases of most of the trees in the flats because of rhodo, so I just took girths and shot up into the crowns to approximate height.
In the flats between the forks:

Tuliptree- 14'4" cbh, app. 135'
Hemlock- 12'6" cbh , app. 140
Tuliptree- 17'7" cbh broken top, app. 110'
Tuliptree-14'5"cbh app. 150'
Tuliptree-app. 15'cbh, 156' (base unclear)
Tuliptree 15' 10" app. 145'
Buckeye- app. 135'
East side:
Cucumber magnolia- 135.4
Black birch- 100.6'
Hemlock- app. 11'cbh, 142.3
Blackgum-7'8" cbh, 114.9'
Tuliptree-app. 13'cbh, 124.8

On the way up to McKee Branch, along Caldwell Fork trail, I counted rings on a couple of trail-cut hemlocks. One was cut about 10' from the base, and I got 432, another was cut about 40 feet from the base, I counted twice and got 461 and 470, I guess it's somwhere close to that. The rings in the center, that far up the trunk, were really tiny. That is one old tree. It'd be nice to cut slabs off some corpses up there, and I suppose soon enough there will be plenty. Of course the forest floor was dusted with adelgid fuzz. The hemlocks up McKee like the ones in most of lower Caldwell are, while infested, not as far gone as the ones in upper Caldwell fork I saw last summer.

Mike