Striking out on a mid-week trek, I wanted to observe the native plants and habitats of the Santa Monica Mountains in May. The weather was still cool and slightly overcast in the morning (what the weatherman calls May grey) but it had burned off by the time I arrived. You could still get a feel for the moisture in the air as you moved through it.

Invasive Species

One of the first things I noticed was how profuse the invasive weeds were. Much like what I observed in the Sepulveda Basin the day before, Maltese Star Thistle (Centaurea melitensis) and annual yellow sweet clover (melilotus indicus) were all along the entry trails and sides of the fire roads. This was in addition to the profusion of yellow mustards. I didn’t stop to check closely, but it looked like the same short pod mustard variety growing in the valley open spaces below. Here it was all along the roads and trails. My guess is that it is easily carried by vehicles and feet passing by once it’s set seed. 

While the sweet clover and thistle looked parched (likely with the now lower soil moisture) the mustard was a lush, turgid green seemingly full of moisture thanks to their long taproots. I had to resist the urge to pull them as I walked by. Maybe a silver lining too so many flowering invasives, the butterflies and European honeybees seemed to be enjoying them. The butterflies looked to be variable checkerspot (Euphydryas chalcedona) which was in great profusion flittering from mustard flower to mustard flower. I wasn’t measuring, but with every pace along the entire journey, I observed no less than one checkerspot, in many of those paces seeing 2 or three in the span of my stride. 

Happy buckwheat and sage

Other plants that looked happy in the space were the Buckwheat (Eriogonum fasciculatum) and the sages (California Sage – Artemisia californica and the Black sage – Salvia mellifera). Under full sun and on the flat surfaces of the hilltops, the buckwheat was in full bloom. So too were those on the south-facing slopes. The flowers looked young and fresh in the season. Around them, the buckwheat hosted many bees, grasshoppers, hoverflies, and butterflies. Those plants on the north-facing aspect seemed to be having a slower start to their season.

So too were the sages, both black and California sage. Much of the black sage had been in bloom for several weeks with, now, tired-looking flowers. The “cowboy cologne” California sage was looking resplendent in the season, though not yet in flower. My guess is the late warmth of spring is causing it to lag. This follows with my observations of other similar plants that I check weekly in the basin. I’m seeing what seem to be similar seasonal delays in setting flowers. The plants, however, look turgid with moisture and smelled heavenly when brushed by them.

Amongst the sage and buckwheat were several of what looked like Rock Phacelia or maybe Mountain Phacelia (Phacelia californica or Phacelia imbricata ssp. imbricata) happily inhabiting the space growing profusely with the other sage/chaparral plants in the community. Another neat find was the deerweed (Acmispon glaber) thriving and in bloom with columns of small yellow flowers. This plant was also all along the side of the fire road and steep slopes of the hill seemingly in bloom on the southern aspects and ready to bloom on the others.

Not surprising was the volume of invasive grasses and oats all along the road and trails. It was hard to quantify the types or varieties throughout but much of it was dry and setting seed, already through its early growing season. I would like to go back and collect some samples from the space to compare in the future to see if they remain, take hold, or get eradicated. I suspect they will continue to spread with no native competition.

Read: Becoming A Naturalist

Sage Chaparral Communities

All along the hillsides of the fire road, there were many large laurel sumacs, lemonade berries, and toyons—each in various stages of bloom. I stumbled upon a lemonade berry on a northern aspect already setting its sticky and hairy fruit. Having grown these plants from seed, I have a fondness for them. Chamise, too, was getting ready to explode in bloom on the northern aspects. Many of the plants were covered in creamy white and green flower buds just on the edge of the opening. Another plant in this community ready to burst was the hairy ceanothus (Ceanothus oliganthus).

Anthropogenic Impacts

Bisecting the plant community, the fire roads themselves were very wide and looked to be recently maintained. They were very wide with few passersby. I encountered only a handful of trail runners (no fellow hikers) and as many mountain bikers. All in all, given it was a mid-weekday, the trail was quiet and open with not much in the way of human congestion. One thing worth mentioning is the impact of humans as a good many animal/nature lovers leaving bags of dog excrement along the path. As a user of the trail, I suppose I’m grateful that the dog owners harvested the poop and put it in the proper bright-colored bag. But I’m confused as to why they would leave it on the trail in plain sight of any passerby. I suppose people just don’t get the concept of “leave no trace” when it comes to walking their dog.

Garapito Canyon Trail

At this point in the journey, I arrived at Garapito Canyon trailhead, which was about a mile and a half from the parking lot. This path wasn’t on my original trek plan, but seeing the return trail to Mulholland Road was closed (parts had washed out making it impassible) I choose to instead investigate down into the canyon.

The path down follows a narrow trail that parallels a creek seep from the top of the hill creating a very narrow slot canyon. The footpath is very overgrown with encroaching grasses and mustard plants. Many of the plants along the side of the trail were mature and lush, except for the grasses and mustard at the start of the path. My guess is the top was the victim of fire road rehab with a mass of disturbed soil and no replanting. Nevertheless, once into the canyon, the native plants proved to be a great delight of tightly growing habitat along a slow-flowing creek with several small crossings as the trail wound its way downwards.

Some of the more interesting finds along the Garapito trail were several tall Sycamores jutting up from the floor of the creek bed. In one spot, a tall sycamore grew alongside a tall toyon as though the two were in a symbiotic competition towards the sunlight above. A short distance further, a colony of hummingbird sage (Salvia spathacea) huddled under another sycamore. It was an absolute delight to stumble across it in situ, under a shady canopy on a very quiet trail. Another surprise was a very mature colony of wavy-leafed soap plants (Chlorogalum pomeridianum), some about to bloom—just along the trail. In total, I counted 19 plants in this colony of various ages, each looking haggard, but happy and growing well in the space. The ones ready to flower had stalks nearly 5 feet in height and flowers just days from opening.

Not only was the trail full of plant life, but so too did it team with an abundance of birds and insects. Of note, I recorded several butterflies (more checkerspots, orange tips, and Bernadino Blue) but also orange wing grasshoppers, Pacific velvet ants, towee birds, and woodpeckers. It was further evident that, in the grasses along the trail edges, some larger mammals pressed their way through making some large transit paths and littering the trail edge with scat. I even happened upon the slithering S track of a snake freshly crossing the fire road above.

It was at this point, about halfway into the trail that I made my way back up the trail to the start of my journey. The sun was nearing its zenith and bringing with it the heat. Exploring just a few detours back to the front, I spent some time at the park entrance reading the signage on the history of the space and ended my excursion sitting at a picnic table enjoying the cool breeze flowing under the shade of a tree.

Field Observations

• Discarded bags of dog poop (several).
• Walkers/Trail runners.
• Mountain Bicyclists.
• MRCA work crews (very friendly).
• Lots of butterflies, lizards, mustard, and invasive grasses.
• Wide and well-groomed fire roads.

Observed Species

• Poison Oak – Toxicodendron diversilobum
• Coast Live Oaks – Quercus agrifolia
• Western Sycamore – Platanus racemose
• Toyon – Heteromeles arbutifolia
• Lemonade Berry – Rhus integrifolia
• Sugar Bush – Rhus ovata
• Wavy-leafed soap plant – Chlorogalum pomeridianum
• Black sage – Salvia mellifera
• Southern Bush Monkeyflower – Diplacus longiflorus
• Chaparral yucca – Hesperoyucca whipplei
• Twining Snapdragon – antirrhinum kelloggii
• Cliff Aster – Malacothrix saxatilis
• Parish nightshade – Solanum xanti
• Deerweed – Acmispon glaber
• Mahogany Jerusalem Cricket
• Orangetips butterflies – Anthocharis cardamines
• Bernardino Blue butterfly – Euphilotes bernardino
• Pacific velvet ant – dasymutilla aureola
• Silverpuffs – Uropappus Uropappus lindleyi
• California Orange Winged Grasshopper – Arphia ramona
• Hummingbird sage – Salvia spathacea
• Chamise (greasewood) – Adenostoma fasciculatum
• California Sage – Artemisia californica
• Rock Phacelia – Phacelia californica
  • or could be Mountain Phacelia – Phacelia imbricata ssp. imbricata
• Buckwheat – Eriogonum fasciculatum
• Maltese Star Thistle – Centaurea melitensis
• Annual yellow sweetclover – melilotus indicus
• Hairy ceanothus – Ceanothus oliganthus

An impromptu trip around the Wildlife Reserve to look at recent plantings (habitat restoration with CNPS LA/SMM and L.A. Sanitation and to get a feel for the state of the invasive mustards and grasses in May.

Most everything was still green and lush. This is on the heels of lots of recent rain from a very wet winter. Add the cooler overcast mornings and threat of monsoonal like rains and the planting/growing season is reaching into late May and early June. In particular, the last several days in the San Fernando Valley have been gloomy and overcast to start, burning off to warm, almost hot, afternoons. Summer is just over the horizon.

Like much of the flowers and blooms, the Sepulveda Basin has been slow to show flowers and is enjoying a late into the season bouquet. The clarkia are still a taunt pink, purple and fuchsia—just starting to set seed. The poppies, as sparse as they may be, are vivid and eye grabbing, mixed into the tall invasive grasses and mustard. And lupine showing their purple spears poking through the brush. Normally I would consider this landscape as mostly sage chaparral, but with the invasion of non-native plants, it’s become more a grassland meadow. I’m worried this will be problematic as we get into fire season.

Read: June Wildflowers in Bloom: A Colorful California Delight

The mustard gets its own mention as they have become nearly 6 feet in height in some places. Each plant is a happy oasis of green and yellow choking out anything that tries to get in its way. To say its thick would be an understatement. But you can see how the areas that the California Native Plant Society and Friends of the LA River have worked to remove it have allowed the native plants to get a foothold.

An interesting consequence of this mustard removal is where other invasives have moved in and established residence. In particular, annual sweet clover (Melilotus albus) and Maltese or Napa star thistle tocalote (Centaurea melitensis). Both have carpeted areas and are growing unchecked. Good that it’s not mustard, but no-less problematic as mono-crops occupying the space growing and ready to set seed.

Also of note, different types of mustard are flourishing. In the east field, Hirschfeldia incana (or short pod mustard) is springing up in areas untouched in years since the fire in 2019. In the west, Rapistrum rugosum (better known as bastard cabbage or turnip weed) is flourishing. Unsurprisingly, the mustard spread seems to be following the paths of humans and their companions. Mustard lines the trail edges and carried by foot and fur as people, dogs, bicycles and joggers enjoy the space. In some locations, the mustard encroaches both sides of the path creating a canopy of mustard “trees.”

Along the path in the west field on the north side, I did happen upon a racquet ball sized wasp gall in a Valley Oak (Quercus lobata). It had a great deal of heft and density to it as I tested its weight in the tree. It looked to be fresh if that’s possible.

The one last observation of note was the density of the California wile rose (Rosa californica). On the lake side, the rose is absolutely flourishing. So much so that it forms thickets that would prohibit the most armored of gardeners wading into it. Almost nothing can grow out of it. I say that as a toyon (Heteromeles arbutifolia) our group planted in 2022 is sending stems vertically rather than horizontally trying to catch and hold the sunshine. It’s good to see it fighting for the space but I worry the struggle may be more than it can bear.

I should note, the Hollyleaf Cherry (Prunus ilicifolia) blooms are on their way to setting fruit. Still present but looking tired. And the Golden Currant (Ribes aureum) are outstanding. Most of the berries are a deep red-gold with a few ripe for the picking (and tasting). Sweet with a hint of tart. It’s a fantastic treat out in the field. I make it a point to stop and try them whenever I happen upon them.

With that, my observation trip was complete, and I made my way back to the parking lot and concluded my observation trip.

Field Observations

• Lots of invasive mustard and grasses.
• A few people walking and enjoying the space.
• Some walkers had dogs; most were off leash.
• Restoration plants were doing well.
• A few critters (cabbage moth and sphinx moth caterpillar).
• A wasp gall in a valley oak.
• An unopened Trojan condom on the path.

Observed species

• Valley Oak – Quercus lobata
• Mustard – Rapistrum rugosum
• Mustard – Hirschfeldia incana
• Maltease Star Thistle – Centaurea melitensis
• Annual yellow sweetclover – melilotus indicus
• Elegant Clarkia – Clarkia unguiculata
• california poppy – eschscholzia californica
• California Wild rose – Rosa californica
• Toyon – Heteromeles arbutifolia
• Hollyleaf cherry – Prunus ilicifolia
• Golden Currant – Ribes aureum

I began this excursion by entering from the north of the lake. My first encounter was the shouldering remains of what looked like a campfire beneath a large poplar tree. The poplar tree has a wide sweeping open space around its trunk with all the leaf litter and debris (literally) broomed away by the now, absconded camper. Having burned close to the trunk the fire had been dealt with by another passing naturalist. 

This visit was to do a bit of reconnaissance and species observation.

The surveying was for upcoming fall planting west of Haskell creek into the open field that opens out to Victory Blvd. As a wild space, it’s been woefully neglected and ravaged by years of neglect and damage from repeated fires.

Burning to the ground in 2019, the Sepulveda Basin Wildlife Reserve became a moonscape of ash replaced with mustard, weeds, and fennel. The planting plan for 2022-23 is to install 60-70 different individual plants:

• Trees (sycamore, oak, and bay laurel)
• Shrubs (toyon, lemonade berry, sugar bush, and laurel sumac)
• Herbaceous scrub (several sages, buckwheat, and other pollinator and bird-friendly species).

I’m hopeful that this mix and volume of planting will jumpstart a natural process in the space that we can build on in the years to come.

Past Plantings

Checking on plantings from 2021-22, many of the installed plants in late 2021 and early 2022 seem to be thriving. Most have survived their first season in the wild. The three Toyons from 2020 have tripled in size as have buckwheats and Artemisia Californica planted in 2022. Milkweed seems to have found some footing on the north side, making it to fat fluffy seeds ready to float away on the breeze.

South of Burbank

Moving through the tunnel to the south (dam) side of the Sepulveda Basin wildlife reserve revealed jewels amidst the dry invasive mustards and grasses. Along the path that parallels Burbank Blvd. are a few sugar bush (Rhus ovata), toyon (Heteromeles arbutifolia), lemonade berry (Rhus integrifolia), and buckwheat (Eriogonum fasciculatum).

These native gems were stand-outs against the fields of mustard that had been left to take over the space. Another gem was a stand-alone majestic oak. This grand old tree was hard to miss.

Also, not hard to miss was the burn scar from an arsonist or encampment that occurred in the last week of July. As I heard it, the Los Angeles Fire Department ran a bulldozer through and cut a tiny loop fire line around it. I’m sure the fire had a big impact, but the brute force of the dozer line added to the damage. Ash and charred vegetation ringed by dozer tracks. I’m not sure what a better solution would have been. Maybe better management of the space? More patrols and more enforcement? Most of the city resources are stretched so thin. 

Through the dam side of the reserve, I made a wide loop to where the Los Angeles River runs into the Sepulveda Dam and circled back up through the tunnel and back to the parking lot. Temperatures had reached a hot and humid 100, give or take, and the air felt heavy. The open space was teaming with people fishing, flying drones, and riding single-wheel dirt scooters. What I didn’t see were a lot of were people soaking in nature around in the open space of the basin.