The lower portion of this route is the most traveled winter line on the mountain. Called “Broadway”, the area just above tree line is commonly frequented by tele, randonee, and boarders for its safe ascent/descent during winter storms. Once above tree line, it’s a pretty straight forward line along the broad ridge leading to Green Butte. This section is an exercise in wind survival during storms. There is not much cover for "bivy" sites between 8,000 and 10,000 feet, or higher for that matter. That said, in the shallow dip between high points on Green Butte and Sargents Ridge, will provide the best options, albeit exposed. Keep in mind that Mt. Shasta is “multi-use” and Old Ski Bowl (OSB), just to the east, is outside of the wilderness. Snowmobiles often frequent OSB, so don’t expect a quiet wilderness get away during the day as sledders can challenge the camp aesthetics. From Green Butte, the route is a beautiful line joining Sargents Ridge at approximately 12,000 feet. The bonus of this route is that you will get to enjoy the best challenges of Sargents Ridge as well. Early season it’s a great route with magnificent exposure along the upper third of the route. If you bivouac low enough you can descend via Avalanche Gulch and get in a fun ski/board descent, as well.
Mid and late season this route is void of snow, and is not recommended. If conditions are favorable, and you are in good physical shape, you can do it in a day.
Winter conditions have brought measurable amounts of snow coverage to Green Butte Ridge and the other ridge routes on Mt. Shasta. Snow depth varies depending on elevation from around 13 inches just below tree line (7,800 ft.) to close to 6 feet at higher elevations (10,000+ ft.). The Green Butte Ridge route is popular with backcountry skiers/boarders, but folks will probably want to hold off for a while longer for a ski tour as there is not quite continuous snow from Bunny Flat trail head to treeline. Climbers will want to wait for spring for a climb of this route. If you choose to attempt a winter climb wait for a solid weather window and stable snow conditions.
There are only a couple bivy sites along the ridge top which are fully exposed to the elements. Flat terrain can be found not too far below the ridge top proper. Many will find camping down in the Old Ski Bowl, east of the ridge, to be much better during any sort of inclement wind events. That being said, you should only consider an ascent of this route when there is at least a solid few days of good weather. The crux of the GB ridge route is before The Thumb and along the "sawtooth" section of the ridge where it joins the Sargents Ridge. Most choose to climb along the west side of the ridge and route-find through rock bands. A few might try the east side of the ridge, though many have been turned back due to very steep traverses. One will notice the high consequence falls down narrow "pin ball" gullies that lead into Mud Creek Canyon and the Konwakiton Glacier area. Move fast and efficiently when climbing this route. Two days is advised, but conditions may warrant three days. Be very careful when traversing the sawtooth portion of the route as long falls are possible into Avalanche Gulch. This route does not see good conditions for long. It is best during the spring time. Prior winter mountaineering skill and experience are a must. Have the proper stout winter worthy gear and equipment. Otherwise, we recommend to wait until next season or choose another route.
As with the Casaval Ridge route, many climbers choose to descend Avalanche Gulch. This is a good option as the traverse back to Green Butte ridge from the Lake Helen area (back to your camp) is on a westerly facing slope and does not see the loose wet avalanche problem often encountered on the southeast aspect of Casaval. Call if you have questions.