Pluto’s Cave & Haystack (Northern California) 12-Dec-2016

Pluto's Cave Northren California

Northern California’s Shasta Valley, a wide valley extending north from the foot of Mount Shasta, is a pocket of high desert resulting from Mount Shasta’s orographic seizure of moisture from east-bound Pacific storm systems. This wringing-out of the waters creates a sagebrush/juniper biome strikingly at odds with the moist, green forests found just a few miles to the south or north. This orographic lift also raises the odds for sunny, snow-free hikes during the winter months – a possibility we were alerted to by the excellent Hike Mt. Shasta website.  So, when the forecast for the Shasta Valley was for clear and sunny (but colder than squat), and our local forecast offered only more rain and gloom, we went south to explore Pluto’s Cave (Pluto Cave on the USGS map) and hike up near-by Haystack.

We exited Interstate 5 on to Siskiyou County Road A12 at Exit 766, then went south on A12 for about 16 miles to a near invisible dirt road going southwest (right). There’s a Pluto’s Cave sign set back from A12 and a hand-made sign nailed to a telephone pole next to the dirt road but both are easy to miss. It was then a short (0.25 mile) drive on the two-track dirt road to the trailhead (parking for 4-6 cars, picnic table, no toilet). There’s a signboard at the trailhead and the trail out to the edge of the cave (it’s actually a huge lava tube) is well-used and easy to follow. It was a near perfect, but grippingly cold, bluebird day and we had good views out over the juniper forest east to Herd Peak and south to the looming mass that is Mount Shasta.

Pluto's Cave Northern California
Herd Peak (center), with Sheep Rock on far right
Pluto's Cave Northern California
Mount Shasta looms

After a short (0.3 mile) hike on the use trail, we came to the lip of where the roof of the lava tube had collapsed,

Pluto's Cave Northern California
Looking north from the edge of the cave

and then did the easy climb down into the tube.

Pluto's Cave Northern California
Into the tube

The lava tube that is Pluto’s Cave was formed by an eruption – 190,000 years ago – of basaltic lava from a vent about 8 miles to the northeast, between Deer Mountain and The Whaleback.  The cave was used for generations by Native Americans but the first non-indigenous person to discover it was Nelson Cash in 1863, who found it while gathering stray cattle.  He named it after Pluto, the Roman god of the underworld (no Disney characters were involved).  John Muir visited this area in 1888, and in Steep Trails (1918), wrote that: On the north side of Shasta, near Sheep Rock, there is a long cavern, sloping to the northward, nearly a mile in length, thirty or forty feet wide, and fifty feet or more in height, regular in form and direction like a railroad tunnel, and probably formed by the flowing away of a current of lava after the hardening of the surface.  At the mouth of this cave, where the light and shelter is good, I found many of the heads and horns of the wild sheep, and the remains of campfires, no doubt those of Indian hunters who in stormy weather had camped there and feasted after the fatigues of the chase.

Where the trail reaches the floor of the tube, it’s possible to go either right (northwest) or left (southeast). We started by going into the southeast branch, which aside from being strewn with graffiti, also seems to be a nesting place for (judging by the poop stains) large predatory birds.

Pluto's Cave Northern California
The graffiti-defaced southeast branch of the tube

The southeast branch only goes about 100 feet or so before it is blocked by a roof collapse that also created a skylight.

Pluto's Cave Northern California
The skylight at the end of the southeast branch of the tube

At that point, we turned around and made our way back to where the trail first enters the tube,

Pluto's Cave Northern California
Back to the entrance of the left branch of the tube

and then headed northwest into what turned out to be the main part of the tube. We crossed under an arch formed by a remaining section of roof,

Pluto's Cave Northern California
The arch in the northwest (main) branch of the tube

and went through another open area and into a still fully intact stretch of tube where we got our first glimpse of how tall it is – at least 40 to 50 feet at its center. Much bigger than all but one we visited at Lava Beds National Monument and also much taller than some others I’ve traversed in far eastern Oregon.

Pluto's Cave Northern California
The northwest (main) branch of the tube; the LovedOne (arrow) is 5 feet tall

We could see a spot of light at the back of this section of the tube and going toward that light brought us into a not-as-tall, but wider, stretch of tube with a big chunk missing from its roof. Judging from what’s online, this is one of the most photographed parts of this tube.

Pluto's Cave Northern California
The “skylight room” in the northwest (main) branch of the tube
Pluto's Cave Northern California
The skylight was formed by a roof collapse
Pluto's Cave Northern California
A view from leaving the “skylight room”

We followed the use trail along the bottom of the tube through another open collapsed section filled with winter-dormant plants and shrubs, to the mouth of the longest unlit section of the northwest (main) branch of the tube,

Pluto's Cave Northern California
Going toward the mouth of the unlit tube

and started into it. Accounts of how far in you can go vary but the Forest Service says that it’s safe to go in 1,200 feet or so before the tube pinches out in another roof collapse. While we had headlamps with us, we decided to stop here mainly because wandering along an uneven floor in the near-dark didn’t appeal. We also didn’t have breathing masks. The motes in the sunbeams and the back-scatter we got when using the flash  revealed that the air was filled with extremely fine dust (some of which is likely finely ground bird poop) – the very kind of particle you DO NOT want to inhale. So we decided to surface for sunshine and fresh air!

Pluto's Cave Northern California
Fine dust motes at the mouth of the unlit tube

Up top, there’s a reasonably evident use trail that allows you to make a loop back to the trailhead through the juniper forest,

Pluto's Cave Northern California
Back to the trailhead through the forest

with views of Sheep Rock and The Whaleback to the southeast,

Pluto's Cave Northern California
An opening to the tube, with Sheep Rock (S) and The Whaleback (W,) beyond

and Mount Eddy and the Scott Mountains to the west.

Pluto's Cave Northern California
Mount Eddy (E) and the Scott Mountains (S) on the western horizon

One reason we were out here was because this is high desert country, and thus drier than our usual haunts just a little further north. Yet if we looked down into the microclimates formed behind rocks or deep under some of the trees and shrubs, we could find small colonies of moss and mushrooms (this season’s signature “plant”).

Pluto's Cave Northern California
A small patch of moss and mushrooms holding out at the base of a juniper

From Pluto’s Cave, we drove back to A12, then south to Highway 97, and a short ways west along that to the trailhead for Haystack (1,269 feet).  We parked at what we thought was the trailhead – a large area on the north side of Highway 97 – only to discover later that we’d stopped too soon.  The road to the summit actually starts at a green ranch gate about 500 feet further west.  No worries, we found an opening in the deer fence and went a short ways cross-country to connect with the old road.

Pluto's Cave Northern California
The old road below Haystack

We followed this road for several hundred feet to a junction and turned left there (northwest) to start our climb up.

Pluto's Cave Northern California
Starting up the old, old road to Haystack’s summit

From this old road, we had a nice view due east to Yellow Butte – another fun hike similar to Haystack – and the hills beyond.

Pluto's Cave Northern California
View east from the Haystack road: Herd Peak (H), Sheep Rock (S), Yellow Butte (YB), Deer Mountain (D)

On Haystack’s basically flat top, we found a summit register (which now contains a rare VanMarmot business card),

Pluto's Cave Northern California
Pawing through the summit register on Haystack

and a benchmark, but weren’t sure if there was supposed to be a geocache here too.

Pluto's Cave Northern California
The benchmark on Haystack

From the top, we had that same view to the west, only now we were high enough to just make out the snowy Trinity Alps.

Pluto's Cave Northern California
Looking west from Haystack: Mount Eddy (E), Scott Mountains (S), Trinity Alps (T)

And, of course, Mount Shasta filled the horizon to the south – showing what looked like less snow than you’d expect for this time of year (but the storm currently blowing through here today ought to fix that).

Pluto's Cave Northern California
Looking south toward Mount Shasta
Pluto's Cave Northern California
Mount Shasta

After failing to find a local lunch spot in Weed, we settled for a regional chain diner in Yreka, and then headed back over into the gloom on the north side of the Siskiyou Crest. Not much of a hiking day (3 miles total, with only 300 feet of elevation gain) but the cave/tube was an excellent experience and the fully sunny view from Haystack was just what we needed to refresh our spirits going into more of Winter’s gloom!

Pluto's Cave Northern California
Our short, short tracks at Pluto’s Cave and Haystack

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