Historical extent of permanent snow fields

[wnshall]

Forest Service maps for Mt Hood, even the 2016 versions, show narrow fingers of permanent snow fields extending down in many places on the mountain. Some prominent examples are the narrow valley where the Vista Ridge trail joins the Timberline trail, the Ladd Creek crossing just East of Cairn Basin, the creek crossing West of Cairn Basin (maps show this snow field extending far down the creek valley, below Cathedral Ridge). None of these areas have permanent snow fields today. My understanding is that the main Forest Service topo maps were updated in the '60s. What I'm wondering is, did these places really have snow year-round back in the 60s? Does anyone have personal knowledge/experience hiking Mt Hood in the 70s, 80s, or 90s and seeing these snow fields? Just curious about the timescale of the change going on.

I suppose a related question is, when will maps be updated to show more realistic permanent snow field boundaries?

[Splintercat]

The did, indeed -- at least what I saw back in the mid-70s and 80s. Some were more stable than others from year to year, but there was a LOT more snow well into summer. There were a bunch of spots on the Timberline Trail where the route crossed perpetual snow and one way to spot them is the generally terrible "trail" that exists today in these ares now that the snow has become seasonal. One prominent example is between Gnarl Ridge and the Cooper Spur junction -- there used to be a series of permanent snowfields that had to be crossed where now you have to stumble through boulders on user paths, as the USFS has never built proper trails where the snow once existed (something I'm working on via TKO).

One in particular that shows up on the topo sheets if you look closely is the very bottom of the Zigzag Canyon. There used to be amazing snow tunnels there well into the 80s where the TT crosses the creek -- both upstream and downstream. The falls just upstream from the crossing used to drop into a snow tunnel!

-Tom

[wnshall]

The did, indeed -- at least what I saw back in the mid-70s and 80s. Some were more stable than others from year to year, but there was a LOT more snow well into summer.

Wow, well into the 80's huh? That's kind of amazing to think it's changed so much in such a short time.

One prominent example is between Gnarl Ridge and the Cooper Spur junction -- there used to be a series of permanent snowfields that had to be crossed where now you have to stumble through boulders on user paths, as the USFS has never built proper trails where the snow once existed (something I'm working on via TKO).

I was thinking of this segment as another example, although even I can recall times crossing some snow fields at the highest points on the trail there.

I first started hiking Hood around 2000, and while I can't remember for sure, I feel like I crossed more snow fields back then than I do now. For example, I feel like the area where Vista Ridge trail joins the Timberline trail had snow into the summer much more than now. And I'm pretty sure the whole slope heading up above where Vista Ridge trail crosses that snow tongue, up towards the more or less permanent snow field above, was mostly open and devoid of tree saplings: now it's crowded with 6' mountain hemlock.

So I guess it makes sense: trees slowly expanding into these areas that were formally under snow most of the year until 20-40 years are now reaching significant size.

One in particular that shows up on the topo sheets if you look closely is the very bottom of the Zigzag Canyon. There used to be amazing snow tunnels there well into the 80s where the TT crosses the creek -- both upstream and downstream. The falls just upstream from the crossing used to drop into a snow tunnel!

That is very cool.