Category Archives: nature|botany

Trying to Use AI to Solve a Malibu Creek State Park Plant Mystery

Terminal leaf cluster of Purple Clarkia (Clarkia purpurea), after it has flowered.

Recently, while doing the Bulldog Loop in Malibu Creek State Park, I noticed a peculiar plant about a half-mile up the Bulldog climb. The linear, red-tinged “petals” were unusual in the early morning light. I snapped a photo of it, planning to identify it later.

When I looked at the photo later that day, I couldn’t ID the plant. Hoping to get some hint about its identity, I tried various “AI-powered” searches and apps. This included Google Lens, Bing Visual Search, Pl@ntNet, iNaturalist Seek, PlantSnap, Flora Incognita, LeafSnap, and others. The most common matches were air plants such as Tillandsia ionantha and various species of paintbrush.

This wasn’t a huge surprise. The AI-based applications were having the same problems I was having — they were not “familiar” with this particular stage of the plant’s life cycle. They also were not keying on an important element of the image.

After a few days without any progress identifying the plant, I headed back to Malibu Creek State Park to take a closer look at the plant.

That turned out to be more challenging than expected. Even though I had the plant’s GPS coordinates, the time of day was different, with different lighting. The plant was also less colorful than before. I walked up and down a 30-yard stretch of Bulldog fire road several times before finally seeing it.

Once located, it didn’t take long to find examples of the plant at an earlier stage of development. In one case, with leaves on the stem and another with leaves and a flower. This helped solve the mystery.

It turned out the plant was one with which I was familiar — Purple Clarkia (Clarkia purpurea). The title photo is after the plant has flowered and all but a terminal cluster of leaves on the stem have wilted. The 8-grooved, elongated-football-shaped structures intermixed with the leaves are ovaries. These are distinctive. A human expert would have immediately zeroed in on these.

The flowers of Purple Clarkia are usually much larger than seen here. They are typically purple-pink with a wine-red spot on each of the four petals. However, the color of the flowers varies, and wine-colored flowers are not uncommon. The size of the flower also varies. Jepson mentions that the subspecies intergrade extensively.

Using the photo of the plant in flower, some of the AI-based apps identified the genus as Clarkia and/or the species as purpurea, or at least included Clarkia among their suggestions.

Sculpted in an Elfin Forest

Gold dust lichen on big pod Ceanothus along the Garapito Trail.

Sculpted in an elfin forest, this fused, twisted and fluted trunk of a big pod Ceanothus is accented with gold dust lichen, a lichen of the genus Chrysothrix — probably C. granulosa or C. xanthina.

From this morning’s Trippet Ranch Loop trail run from the End of Reseda (Marvin Braude Mulholland Gateway Park).

Manzanita Leaf Galls and Aphids

Manzanita Leaf Galls and Aphids

Was running down the Chamberlain segment of the Backbone Trail Saturday, when a flash of bright red on a manzanita bush caught my eye.

Very bizarre, as nature often is. At first glance I thought the bulbous red objects on the manzanita were some kind of larvae, but on closer inspection could see it was a swelling of the leaf. My first thought was some kind of viral infection.

What they turned out to be are aphid induced leaf galls. Galls generally provide a protective habitat and enhanced food source for the inducing species and their tenants.

Related post: Scrub Oak Apple Gall

If It Looks Like a Hummingbird and Flies Like a Hummingbird…

hummingbird moth feeding on spreading larkspur

I was on the way back from Mugu Peak and about four hours into my run. I’d stopped at an exposure of Miocene age shale along the Upper Sycamore Trail. The gray-brown rubble is home to an intensely blue-purple wildflower called spreading larkspur (Delphinium patens ssp. hepaticoideum).


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I’d just snapped a series of bracketed exposures of one patch of the flowers when suddenly there was the bumblebee-on-steroids buzzing of a hummingbird in front of me.

At least I thought it was a hummingbird. It sounded like a hummingbird and was about the right size. Its blurred wings were shaped like a hummingbird’s. It flew with the precision of a hummingbird, darting from flower to flower, deftly feeding on each blossom’s nectar using its oddly shaped beak.


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But it wasn’t a hummingbird — it was a hummingbird moth — a white-lined sphinx (Hyles lineata). I’d read about hummingbird moths, but to have one suddenly appear and start feeding on a larkspur plant I happened to be photographing was extraordinary.

Apparently the problem of feeding on the high-energy nectar in certain types of flowers is sufficiently definitive as to have produced a very similar evolutionary solution in wildly different organisms.

The sphinx moth is described as flying like a hummingbird, but which lineage produced this elegant solution first? It may have been the moth! A trace fossil of a sphinx moth found in Early Eocene Asencio Formation of Uruguay appears to predate the earliest known Oligocene fossils of hummingbird-like birds! In any case it appears that both hovering moths and birds co-evolved with the flowering plants on which they feed and pollinate.

Related post: Hummingbird Stories

Just Me and the Meadowlarks

La Jolla Valley from Mugu Peak

I had to stop running and take it all in. Soaked by recent rains, La Jolla Valley was renewed and green. To my right a meadowlark warbled its silvery call, and in the distance at first one and then another bird followed in song.

Isolated for weeks by the closure of Pacific Coast Highway and Pt. Mugu State Park, the La Jolla Loop Trail was trackless and in places overgrown. Wet with dew, the mustard choking the trail had soaked my shoes and socks.

Sprinkled among the greens were whites, purples, pinks, reds and yellows of the first stage of a wildflower explosion. A sweet scent drifted on the breeze. Running in the valley was like running in a remote and seldom-visited wilderness.



There had been much to see on the run from Wendy Drive. Before the Park closed in December I had surveyed the aftermath of the December 12 flash floods in Sycamore Canyon, Blue Canyon and Upper Sycamore Canyon. One of the reasons for today’s run was to see what had happened in this part of the Park.

Wood Canyon parallels Sycamore Canyon and is probably its largest tributary. Based on the height of the debris piled against the trees, the flash flood that roared down Wood Canyon must have been astounding! Looking down the stream course reminded me of flash floods I’d seen on creeks and streams during the El Nino’s of 1997-98 and 2004-2005.



Bowl-shaped La Jolla Valley is an independent drainage, separate from Sycamore and Wood Canyons and their tributaries. It acts like a huge rain collector and funnels all the runoff down deeply cut La Jolla Canyon to the ocean. In La Jolla Valley all the creeks were scoured by the flash flooding and the small footbridge west of the group campground was washed out. The vernal stock pool on the Loop Trail above La Jolla Canyon was once again full.



It’s no surprise that the December flash floods washed out the trail in La Jolla Canyon. I can’t think of a steeper and more narrow canyon in the park.  The flow must have been phenomenal! The La Jolla Canyon Trail is closed and barricaded at its juncture with the Loop Trail. Here are archived maps of Rancho Sierra Vista/Satwiwa and Pt. Mugu State Park originally from the NPS Santa Monica Mountains web site. Also see the Pt. Mugu State Park maps on VenturaCountyTrails.org.

In recent years the drought has dramatically reduced the number and variety of wildflowers blooming in the Santa Monica Mountains. Not so this year. Since October 1 Camarillo Airport has recorded 7.0 inches of rain, which is about 92% of normal. Last year over the same period only 0.84 inch had been recorded.



Many species are already blooming and many more will be blooming soon. On today’s run I saw shooting stars, encelia, lupine, nightshade, monkeyflower, paintbrush, California poppy, bladder pod, wild hyacinth, phacelia, wishbone bush and more. A small patch of chocolate lilies were in bloom along the eastern segment of the Loop Trail.

La Jolla Valley and Mugu Peak can be busy places, but today it was just me and the meadowlarks.

Update February 3, 2015. According to the Ventura Star six miles of Pacific Coast Highway from Las Posas Road to the Sycamore Cove Day-use Area reopened today providing access to Pt. Mugu State Park from the south. Note that the La Jolla Canyon Trail is still closed and likely to be for some time.

Some related posts: Pt. Mugu State Park Debris Flows and Flash Floods, Wendy Drive – Mugu Peak Challenge, Laguna Peak, La Jolla Valley, and the Channel Islands

Running Down Diablo

Running the North Peak Trail on Mt. Diablo

More often than not when you run down a mountain, you’ve also had to climb up it. Not so today. Today our Mt. Diablo run started on the summit of Mt. Diablo (3849′), worked over to North Peak (3557′), and then descended the Bald Ridge, Eagle Peak and Mitchell Rock Trails to the trailhead at the Mitchell Canyon Interpretive Center and Ranger Station.

I was more than happy to save the ascent of Mt. Diablo for another day. With the AC100 just a couple months away my mileage has been on the increase. Yesterday, after driving up to San Francisco, Brett had taken me on a run on Mt. Tamalpais. Earlier today I’d done a run to Fort Point and this afternoon would be doing another run when we returned to the city.

Except for an astoundingly steep and slippery section of service road between Prospector’s Gap and North Peak, today’s run was nearly all single track trail. Not the “cruise downhill, don’t have to think about it” kind of single track, but technically interesting single track that tries hard to find a way to trip you up and knock you down.

Mount Diablo fairy lantern
Mount Diablo fairy lantern

One of the reasons for doing Diablo was to see if we could find the rare and endangered Mount Diablo fairy lantern (Calochortus pulchellus). There were a surprising number (50-100) of the yellow flowers along the North Peak and Bald Ridge Trails. It might be assumed that this was due to the area being burned in the September 2013 Morgan Fire, however there appeared to be as many instances of the plant outside the burn area as inside. I think there is another explanation.

The unusual pattern of rainfall that we experienced this rain season in Southern California was replicated across much of the state, including the Bay Area. As of February 1 San Francisco Airport (KSFO) had recorded only 1.5 inches of rain since July 1 and storms in February and early March accounted for a large part of this season’s rainfall.

This pattern of rainfall, sun and temperature appears to have favored wild lilies, particularly mariposa lilies of the genus Calochortus, such as the Mt. Diablo fairy lantern. The butterfly mariposa (Calochortus venustus) was very widespread on Mt. Diablo, numbering in the thousands. It appears to fill a similar ecological niche as the Catalina mariposa (Calochortus catalinae) in the Santa Monica Mountains. The Catalina mariposa was also very abundant this year, along with some other members of the Lily family.

Here are a few photos from the Diablo run.

Coastal Trail Runs and Pacific Coast Trail Runs offer trail running events that start and finish at the Mitchell Canyon Trailhead on Mt. Diablo. Brazen Racing also organizes the Diablo Trails Challenge.

For more information about Mt. Diablo see the Mt. Diablo State Park, Save Mount Diablo and Mount Diablo Interpretive Association web sites. This State Park brochure includes a trail map.

Related post: Diablo Trails Challenge 50K 2018