Category Archives: trails|smmc open space

Running Between Raindrops: Chumash Trailhead to Rocky Peak

Rain in the San Fernando Valley from Rocky Peak. March 12, 2021.
Rain in the San Fernando Valley from Rocky Peak

Was that thunder? I warily eyed the dark clouds over the mountains and pondered the situation.

I was about halfway to the top of the Chumash Trail and was planning to run along the crest to Rocky Peak. The run had started in short sleeves and sunshine, but it was pretty obvious that wasn’t going to last.

Chumash Trail about a mile from the trailhead
Chumash Trail about a mile from the trailhead

A cold upper-level low had brought badly needed rain to the area for the past two days. The low was moving off to the east, but there was still a chance of afternoon showers and maybe even a thunderstorm.

It was the “thunderstorm” part that I needed to pay attention to. I had enough gear to deal with a downpour and cooling temps, but electrical storms are no fun at all.

I decided to continue to the top of the Chumash Trail and reassess. As I worked up the trail, I pictured the counterclockwise circulation around the low, and how convective cells develop over the mountains and then dissipate as they drift south. The concern was that the cells don’t always dissipate.

Rocky Peak Road near Rocky Peak
Rocky Peak Road near Rocky Peak

It looked like things weren’t getting any better at the top of the Chumash Trail, but it wasn’t worse either. I hadn’t heard any thunder for a while, and most of the activity seemed to be a few miles to the west and east. Having been starved of stormy weather for much of the rain season, I turned right on Rocky Peak Road and headed south toward Rocky Peak.

The run from the Chumash Trailhead to Rocky Peak is a challenging mix of technical single-track trail and hilly fire road. There are wide-ranging views of Simi Valley & Simi Hills, the San Fernando Valley, Santa Monica Mountains, Ventura County mountains, and San Gabriel Mountains. On a clear day, the view can extend to the Channel Islands, Saddleback, and San Jacinto Peak.

NOAA radar mosaic Rocky Peak March 12, 2021.
NOAA radar mosaic at the time I was on Rocky Peak

The actual turnaround point for a run to “Rocky Peak” varies. Some like to turnaround at the high point of Rocky Peak Road that is near Rocky Peak. Most of the time, I turnaround at a viewpoint that is at the end of a spur trail that branches off from the high point of Rocky Peak Road. From time to time, it’s fun to hike over to Rocky Peak and scramble to the top. That’s a bit more involved and requires some route-finding.

I felt the first raindrops as I reached the high point on Rocky Peak Road and turned onto the spur trail that leads to the overlook. There was some increased development to the east, but it looked like there would be enough time to get over to Rocky Peak, take a couple of pics, and then head back.

Oat Mountain, shrouded by rain
Oat Mountain, shrouded by rain

I felt a little exposed on top of Rocky Peak. I hadn’t heard any thunder for the past hour, but a cell to the east was spouting heavy rain over the San Fernando Valley, which meant there was probably enough development to produce lightning. I took the title photo and a couple of others and hurriedly descended from the peak.

Back on Rock Peak Road, the sprinkles increased, and the showers became more steady as I ran north toward the Chumash Trail. Under the dark clouds, a raven perched on a large pinnacle cawed incessantly, either enjoying the rain or complaining about it. In the distance, a siren wailed down in the valley. It was cold, and I was very glad to have an extra shirt, sleeves, gloves and a light rain shell.

Mix of sun and rain on the Chumash Trail
Mix of sun and rain on the Chumash Trail.

As I began the descent of the Chumash Trail, the sun briefly broke through the clouds, reflecting brightly on the wet sandstone rocks. I breathed deeply, relishing the smell of the cleansed air and wet chaparral, and continued down the trail.

Here’s an interactive 3D terrain view of my GPS track. Over the run, the temperature sensor on my pack recorded a drop of about 30 degrees — from around 70°F at the start of the run to about 40°F when the showers began! Here’s what a NOAA Radar Mosaic looked like at the start of the run and when I was on Rocky Peak.

Related: Chumash Trail, Rocky Peak, Thunderstorm

Chumash-Las Llajas Loop

Rocky Peak Fire Road between the Chumash Trail and Fossil Point
Rocky Peak Fire Road between the Chumash Trail and Fossil Point

Update of a post from December 30, 2006.

The Chumash-Las Llajas Loop is a scenic 9.3 mile trail run in the eastern Simi Valley. Run counterclockwise, it combines a  strenuous climb on a single-track trail and fire road with a fast-paced 4-mile downhill on a dirt road. The cumulative elevation gain/loss on the loop is about 1600′.

View of Oat Mountain from near the top of the Chumash Trail.
Nearing the top of the Chumash Trail

I like to do the loop starting at the Las Llajas Canyon trailhead on Evening Sky Drive. A short jog up Evening Sky Dr., then across a field, and you’re on your way up the Chumash Trail. From this point, it’s an approximately 1000′ climb over 2.7 miles of rocky trail to Rocky Peak fire road.

After turning left (north) on Rocky Peak fire road, a short downhill is followed by three-quarters of a mile of climbing to “Fossil Point.” A short detour off the main fire road leads to a cairn marking the high point. From here there is a panoramic view of Oat Mountain, San Fernando Valley, San Gabriel Mountains, Santa Monica Mountains, Simi Valley, Boney Mountain, Channel Islands, and Ventura Mountains.

Exposures of fossil shells are found near the high point. According to the area’s Dibblee geology map, these may have been deposited in shallow marine lagoons a couple million years ago.

From the high point, the loop continues north on Rocky Peak Road. At first, it descends steeply, then climbs to a hilltop with a few valley oaks. Partway up the hill, a roadcut reveals the long roots of the chamise plants on the hillside.

Road connecting Rocky Peak Road to Las Llajas Canyon.
Road connecting Rocky Peak Road to Las Llajas Canyon.

Following a short downhill, the road continues past a fallen valley oak that was killed by the 2011-2015 drought. There is a fork in the road here. The road connecting to Las Llajas Canyon goes up a short hill to an overlook of the canyon. From the top of the hill, there are more than 4 miles of downhill through the winding canyon. There used to be oil field equipment on the connector between Rocky Peak Rd. and Las Llajas Canyon, but it has been removed.

If the creek in the canyon is flowing, there are several places where the (usually) small stream crosses the road. In the Spring and early Summer, many species of wildflowers can be found in the canyon.

Cattle on the Las Llajas Loop
Cattle on the Las Llajas Loop

Some of the wildlife, and not-so-wild animals, I’ve encountered on the loop include rattlesnakes and other snakes, deer, longhorn cattle, roadrunners, and a kangaroo rat. Although others have seen mountain lions in the area, I’ve only photographed their tracks.

The loop ends with a short, steep climb up a paved road. At the top of the hill, turn left to return to the trailhead.

Explore the scenery and terrain on the Chumash-Las Llajas Loop trail run using our high resolution,  interactive, 3D viewer. The imagery is so detailed, it’s almost like being there! To change the view, use the control on the upper right side of the screen, the CTRL key and your mouse, or touch gestures. Track and placename locations are approximate and subject to errors. Poor weather, and other conditions may make this route unsuitable for this activity. (It is also possible to start the loop at the Chumash Trail trailhead at the end of Flanagan Dr.)

The title photo is a section of Rocky Peak fire road between the top of the Chumash Trail and Fossil Point. It is from a run on October 6, 2020.

Some related posts: Chumash Trail Rocks & Snow, Exploring Las Llajas, Marr Ranch WildflowersThings Found on the Chumash Trail

Finally — a Few Wildflowers!

Bush sunflower

As of March 1, Downtown Los Angeles had recorded only 1.99 inches rain over the past eight months. Most of that was recorded in one storm in early January. It was the second driest July 1 – February 28 on record.

Following the January storm, temperatures warmed up and stayed relatively warm for much of the next 30 days. In the West San Fernando Valley the high temperature hit 89 °F at Pierce College on February 4, and was over 80 °F for 12 consecutive days. Some plants (and some rattlesnakes) responded as if it was Spring.

In mid February Winter returned, with cool daytime temperatures and cold nights. There were Frost and Freeze Warnings on several nights.

In March the ridiculously resilient ridge of high pressure over the West Coast finally relented, resulting in above normal rainfall. It took awhile, but the March rain and April sun eventually produced an assortment of wildflowers.

Here are some wildflower photos from recent runs at Ahmanson Ranch, Malibu Creek State Park and Topanga State Park.

Red Rock Canyon from the Red Rock Trail

Red Rock Canyon from the Red Rock Trail

Nope, I wasn’t running near Las Vegas or north of Mojave, this Red Rock Canyon is in Old Topanga Canyon, southeast of Calabasas Peak.

Although there’s a trailhead off of Old Topanga Canyon Road, I usually access Red Rock Canyon from the top, using Calabasas Peak Mtwy and Red Rock Road.

Fallen Oak

A large valley oak along Rocky Peak fire road that toppled following five years of drought.

The fallen oak pictured above — one of the larger valley oaks along Rocky Peak fire road — toppled over in the summer of 2016 following five years of drought. Fire and drought are a natural part of the valley oak’s habitat and the trees have evolved to withstand ordinary variations in their environment. However, severe fires or extended droughts, or fire in combination with drought can overcome the tree’s defenses. The drought may have been the culminating factor in the felling of this oak, but fire and other factors may have also played a role.

Base of large valley oak along Rocky Peak fire road that toppled following five years of drought.
Base of large valley oak that toppled following five years of drought. Click for larger image.

According to the Fire Effects Information System (FEIS), the heart-rot fungus Armillaria mellea is usually present in valley oaks and larger oaks tend to be hollow or rotten in the center. The toppled oak was hollow near its base and its interior appears to have been blackened by fire. The FEIS describes instances where the decaying wood in the interior of older valley oaks could ignite in a fire, but leave the exterior bark uncharred.

What fire might have burned the tree? There are two possibilities: the 2008 Sesnon Fire and the 2003 Simi Fire. It probably wasn’t the Sesnon Fire — this photo of the tree, taken about a month after the Sesnon fire, shows little impact. I couldn’t find a photo of the tree following the Simi Fire, but photos taken nearby show a severely burned landscape. Ultimately, it appears fire and drought weakened the tree, accelerating its heart rot and weakening its roots to the point it could no longer support itself.

Photos of the fallen oak are from this morning’s foggy run along Rocky Peak fire road.

Related post: Ahmanson Blue Oak Succumbs to Climate ChangeChumash Trail – Sesnon & Simi Fires