A few days ago I received a wonderfully detailed and insightful email from Roy van de Hoek. Roy is very knowledgeable about local conservation and ecological issues. He has the added distinction of once having worked at Alondra Park – smack in the middle of the Dominguez watershed and adjacent to the Dominguez Channel. There’s a lot of good suggestions and history in his email, so I thought it best to try to reproduce it as completely as possible.
Here’s an edited version of his email after the break.
First, overall, hooray for Dominguez Creek. Sometimes I refer to it as Victoria Dominguez Creek, the Spanish-Mexican matriarch, and how Victoria Avenue near California State University at Dominguez Hill and Victoria Park in Carson got their names. By the way, Alondra, of Alondra Park fame, [link to Alondra Park map] is the name of specific species of bird, the lark, and not the meadowlark, but the Horned Lark, which was the most common bird of Los Angeles County, forming flocks until the early 1900s, of at least 40,000 to 100,000 individuals. It is a bird of the short-grass prairie, which does particularly well where there are lots of ground squirrels and gophers, which help make the bare ground associated with short vegetation that the Horned Lark liked as habitat. Unfortunately, the Horned Lark has become virtually the rarest bird of coastal Los Angeles County, which is quite ironic. Some say it is essentially to be considered locally extinct (extirpated). So, Alondra Park is named for an extinct bird that was also very beautiful in feather-color pattern, but also in its interesting song and calls, not to mention its fascinating behaviors.
As you can see, I’m interested in history, but as Jeanne points out, Jim Osborne [local historian, arborist, and Lawndale City Council member] is very knowledgeable, more so than I, in many regards, but together we paint an interesting story of the earlier natural history and cultural history of the Dominguez watershed in and around Lawndale, Alondra Park, El Camino College, Torrance, Gardena, and Hawthorne.
I’d like to chime in about the idea of restoration, particularly the concept of “prairie” on the tops of the levee walls of Dominguez Creek. I think this is good thinking, to steer away from coastal sage scrub and chaparral species and oak woodland species as we see on so many restoration projects, which also sometimes incorporate Channel Island (Catalina) island species due to the idea of restoration being confused with gardening, horticulture, and landscape architecture, i.e. the designing of natural.
The first thing that needs to be considered is the “native soil” as it usually tells us what was there. In the case of Dominguez Creek, the soils at Alondra Park, El Camino College, and the bicycle path, and levee areas are all 100% hard adobe-clay soils that develop mud cracks when dry. There is not an ounce of loam and sand in these soils. That being said, a particular type of prairie would only be develop, that called ALKALI PRAIRIE, not a bunchgrass prairie of tall grasses. The word alkali, conjures up the notion of SALTS in the soil, which is good genuine truthful thinking. So if we begin by considering salty clay soils we are on the right path to deciding the plants, unless of course we try to change-fake the soil by adding irrigation and mulch to force the soil to become a loam or sandy soil, which will never work with continual unsustainable “ungreen” methods. Geology and geological history and geography with geomorphology shows us why the soils here are salty and clayey. It’s because several thousand years ago, a shallow-water sea and inlet occurred here, where rivers deposited fine materials in an estuary-like and lagoonal setting.
Alondra Island at Alondra Park is an excellent case study. The soils on the island are salty and clayey and develop mud cracks when dry. I asked Jeanne if I could plant Seaside Heliotrope (Heliotropium curassavicum) in her native garden area. It took off and reproduced vegetatively by rhizome and adventitious roots to multiply approximately, 500% in its coverage. I suspected it would do well because there were a couple of remnant species of the short-grass alkali prairie wetland transition still living on Alondra Island. One of these species dominates the island vegetation, namely Alkali Mallow (Malvella leprosa). In fact, this species is a key component of a specialized prairie, which takes it name from this plant, hence, “Alkali Mallow Prairie.” From past field experience in studying California vegetation from field investigations, from reading of old floras and their floristics, and at herbarium study locations, I discovered that the Seaside Heliotrope and Alkali Mallow are close associates. However, Seaside Heliotrope is more succulent and delicate than Alkali Mallow. Hence, the Alkali Mallow survives where the Seaside Heliotrope disappears. After planting Seaside Heliotrope on Alondra Island, I noticed that seeds were dispersed, likely by ducks, from the south side of the island (Jeanne’s garden area) to the north side of the island, a small disjunction. And so now two small populations of Seaside Heliotrope occur on Alondra Island, both growing slowly, until one day, it will be widespread the way that Alkali Mallow is all over the island. Both species have flowers with nectar and pollen that attract many butterflies, moths, bees, robber flies, hover flies, and other pollinator species, which in turn attracts their avian predators such as thrushes (robin and bluebird) as well as flycatchers (phoebe, kingbird, pewee) and other birds that prey on these birds such as the smaller accipter hawks (Cooper’s Hawk) which visits Alondra Island regularly. We can consider the Cooper’s Hawk a riparian hawk and woodland hawk because it flies between trees, and there are many pines on the island that create that woodland-like habitat juxtaposed with the short-grass prairie environment on the island. Jeanne’s native California plant garden is very good because it does have a focus on Catalina Island plants, and Alondra Park Island is an actual island in the park’s lake. Catalina Island birds from Catalina, via the nearby Palos Verdes Peninsula (a former Channel Island coincidentally that was surrounded by ocean), brings the Catalina Island subspecies of the Orange-crowned Warbler and the Catalina subspecies of the Allen’s Hummingbird regularly to Alondra Island. Jeanne’s small sample of a Catalina Woodland-maritime style habitat (ISLAND TREE MALLOW WOODLAND) is nicely displayed. Once upon a time in the geologic past, the Los Angeles Coast would also have had an ISLAND TREE MALLOW WOODLAND, so its not too far off the mark to have a small grove of these clustered together, that Jeanne wisely planted close together to form a canop/ small jungle / like setting. Unfortunately, rabbits and squirrels like the taste of the Tree Mallow, so it is deterred from greater expansion on the island. By the way, the squirrel [that eats the mallow] is from the Appalachian region of the Eastern U.S. and the rabbits are from Europe originally (i.e. aka Belgian Hare).
I also noticed that a small delicate shrub, Euphorbia misera, that I suggested to Jeanne to purchase and which I asked to be responsible to plant, is doing really great. It’s both a Catalina Island species and a mainland prairie-coastal maritime cliff species that likes clay adobe and salt soils. I knew that if planted at the correct depth it would take well on Alondra Island. And so it has. Another native Euphorbia is very common on Alondra Island, naturally associated with the Alkali Mallow, but I can’t recall its specific epithet at the moment, as I write to you.
Regarding a careful interpretation of the desired vegetation to be a prairie on Dominguez Creek because the area for planting is about 15 feet above the creek’s cement walls, and so the roots of riparian species can’t reach water, I think there is some modification to consider here. It’s important to note that the first 100 feet adjacent to a stream, whether natural or artificial, is a special environment in the air, of increased humidity due to evaporation from the water surface of the stream. This atmospheric humidity is high enough to make a partial riparian-wet prairie type environment. Therefore, its a higher water environment, and if combined with the bicycle path runoff which is an impervious surface, the soils adjacent to the bicycle path have a doubling of rainfall infiltration. Therefore, some experimentation with Willow would be good. And I would also try one of the taller prairie grass species, namely, ALKALI RYE (Leymus triticoides). It will do well here alongside the ALKALI MALLOW, which already grows in several locations along the bicycle path on Dominguez Creek. I think that Seaside Heliotrope would be wise to plant alongside the bicycle path on Dominguez Creek too.
My monthly nature-bird walks at Alondra Park are on the 3rd Saturday at 9am. Meet near the lake, near the bridge to the island. By the way, the nest box for the Western Bluebird has been successful again for the second straight year. Four young bluebirds fledged recently. Take good (buen) care amigos de pajaros y animales y flores de Alondra and Aficionados of Arroyo de Dominguez con Aguas del Rio Hondo, when it rains (cuando lluvia), y El Camino de Real en Los Angeles.
“Roy” Robert van de Hoek
PS: I wanted to wrap up this email now with a little biography about me as follows. I’ve been researching Dominguez Creek for 11 years now, both in the area of Victoria County Park (Carson) and Alondra County Park (Lawndale). I’ve had the opportunity to make observations both as an LA County employee and as a private citizen and as a representative of several environmental groups (Sierra Club, National Audubon Society, Ballona Institute, Wetlands Action Network, and Coastal Law Enforcement Action Network). The 11 years of working at Victoria Park and Alondra Park, combined have also provided me with lots of field observations on the Dominguez Creek Watershed. I’m a former instructor at 5 California Community Colleges. After obtaining 2 undergraduate degrees, Environmental Biology and Geography, as well as 2 minors (Archaeology and Geological Sciences) from CSUN. And I did graduate education at CSUN and UNR (Reno) in hydrology, wildlife, and cultural resource management, particularly focused on archaeology and zooarchaeology. Recently I returned to El Camino College to learn about horticultural techniques of propagation, irrigation, landscape design, fertilizers, etc., and obtained a Certificate in Environmental Horticultural Science.
Disclaimer: I’m writing to both of you as the conservation biologist and co-director of the Ballona Institute this morning, although I’m also currently president of a Los Angeles County Audubon chapter, and the chair of the Sierra Club’s Los Angeles River Committee. I say this, because I also work for LA County Department of Parks and Recreation, but Mondays, are my regular day off, and my email to you is not written from a county email address, but an Audubon email address, and the views I express in this email are views of the Ballona Institute and Audubon Society, not in any way official correspondence from the County.