Blainville's Horned Lizard by Michael Marchiano October 1, 1998 The Coast or Blainville’s Horned Lizard (Phrynosoma blainvilli ) is considered to be an odd-looking creature by many people. Squat, flat bodied, and short-tailed with a wide head covered in spines, it causes one to consider the little lizard a miniature relic from the age of dinosaurs. In fact, its appearance gives rise to its nickname, “Horny Toad”. Growing to a length of five inches, this cryptic colored lizard depends far more on its appearance for survival than speed or agility. Its mottled coloration of large and small patches and bands on its body of various shades of brown, black, cream, and yellow allow it to blend into it environment almost to a point of invisibility. When threatened, it will first freeze and hope its camouflage will protect it. If attacked, it will run a short distance, stop suddenly, lay flat, and once again count on its coloration for protection. If grabbed, the horned lizard has a unique defense for repelling its attacker. It can actually squirt a quick stream of blood from the corner of its eyes with the hope of distracting or startling the predator and escaping. Another unique feature of this specialized lizard is its diet. Its primary food is native ants, such as species of harvester and carpenter ants. It does on occasion eat other arthropods such as beetles, crickets, and spiders, but 80-90 percent of its diet is indigenous ants. The introduction of Argentine ants (which have replaced native species) in areas once inhabited by Coast horned lizards has been one cause of their diminished numbers. These introduced ant species are not palatable to the lizard. Although three subspecies of this lizard inhabit California, from Baja up the Central Calley to the Sierra Buttes, the last vestige of these unique creatures in Contra Costa County is Mount Diablo. The overall population of the Coast horned lizard throughout California has been under threat because of habitat destruction, pesticides, agriculture, and the introduction of Argentine ants. Blainville’s horned lizards are generally seen in our coast range and the Central Valley from spring through fall, hibernating in burrows under ground in cold weather. Found in chaparral, mixed oak, and grey pine forest, sandy loam soil, and gravelly areas, these lizards need a mixture of open space and shrubbery with soil they can easily dig into as well as populations of native ants for food. They breed in spring, with the female laying a small clutch of eggs (average 8-12) in a burrow she excavates. Newborns hatch in late summer or early fall and are miniatures of their parents, about the size of a quarter. Once much more common in Contra Costa County, the population has decreased in recent years. On Mount Diablo keep your eyes open, especially on Eagle Peak, Twin Peaks, Black Point, White Canyon, Mount Olympia, and on the south side along Black Hawk Ridge. Because of its specialized diet and environmental conditions, this is a lizard that does not do well in captivity (horned lizards in North America can no longer be sold in the pet trade) so please enjoy them when you see them, but let them be. Enjoy this unique and marvelous creature along with the rest of the natural environment in Mount Diablo State Park. Blainville's Lizard changes color to blend with the soil. | Dan Sandri By Dan Sandri BACK TO LIST

Wildflower Mount Diablo Douglas' Monardella Scientific Name: Monardella douglasii Family: Lamiaceae (Mint Family) Blooms: Jun Color: Blue-Purple Annual herb Native, endemic to California Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Kevin Hintsa

Wildflower Mount Diablo Purple Mouse Ears Scientific Name: Mimulus douglasii Family: Phrymaceae (Monkeyflower Family) Blooms: Feb - Mar Color: Blue-Purple Annual herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants iNaturalist observations

Wildflower Mount Diablo San Luis Stickleaf, San Luis Blazingstar Scientific Name: Mentzelia micrantha Family: Loasaceae (Loasa Family) Blooms: Apr-Jun Color: Yellow-Orange Annual Herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Daniel Fitzgerald Daniel Fitzgerald Daniel Fitzgerald Daniel Fitzgerald

Wildflower Mount Diablo Mount Diablo Globe Lily, Mount Diablo Fairy Lantern Scientific Name: Calochortus pulchellus Family: Liliaceae (Lily Family) Blooms: Apr - Jun Color: Yellow-Orange Perennial herb (bulb) Native This wildflower occurs only on Mount Diablo and in surrounding hills of the East Bay. Look for this flower in wooded or brushy hillsides with northern exposure; frequently in canyons; 700 feet to the summit. This plant is rare, per Cal Flora: California Rare Plant Rank: 1B.2 (rare, threatened, or endangered in CA and elsewhere ). Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring

Wildflower Mount Diablo Chaparral Blazing Star, San Luis Stickleaf, Small Flowered Stickleaf Scientific Name: Mentzelia micrantha Family: Loasaceae (Loasa Family) Blooms: May - Jun Color: Yellow-Orange Annual herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Donna Pomeroy, iNaturalist

Wildflower Mount Diablo Winter Cress Scientific Name: Barbarea orthoceras Family: Brassicaceae (Mustard Family) Blooms: Feb - May Color: Yellow-Orange Perennial herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Steve Beatty

Wildflower Mount Diablo California Fuchsia, Hummingbird Fuchsia, Zauschneria Scientific Name: Epilobium canum Family: Onagraceae (Evening Primrose Family) Blooms: Aug - Dec Color: Red-Pink Perennial herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Kevin Hintsa

Wildflower Mount Diablo Hop Tree, Western Hoptree Scientific Name: Ptelea crenulata Family: Rutaceae Blooms: April - June Color: Yellow-Orange Tree or shrub Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Stephen Smith

Black Phoebe Flycatchers Black Phoebe Sayornis nigricans All Year Flycatchers Daniel Fitzgerald May be encountered in open, semi-wooded, or wooded habitats, usually near water. Easiy recognized by its tail-pumping habits, mostly black plumage, and white belly and undertail coverts. Nest is usually placed on wall of cliff, under bridges, or on side of buildings. Nest is a cup-shaped structure built from mud, plant materials, and animal hair. Feeds primarliy on insects, but may also eat berries or even small fish.

Rugged Plants Contributed by Dan Day Reprinted by permission from the Northern California Geological Society Newsletter A Struggle to Survive on Barren Serpentine Soil January 1, 1999 Mike Woodring Ultramafic rocks are scattered throughout the California Coast Range, the Trinity Mountains, and the Sierra Nevada foothills. That serpentine is the state rock proves it has caught the eye of California geologists. However, many are perhaps unaware that serpentinites have spawned a unique flora specially adapted to survive on their nutrient-poor soils. The adaptive characteristics of one such species was explored in Cheryl Smith’s January 26, 2005, NCGS talk Geochemical Investigation of the Distribution Habitat of (McDonald’s Rock Cress) in the Six River National Forest, Del Norte County, California. Cheryl, current President of the Peninsula Geological Society, did field work in remote Del Norte county on the California-Oregon border studying the geochemical characteristics of soils supporting isolated communities of this rare endangered plant, pictured to the left. (Arabis macdonaldiana ) Botanical and ecological data on this and other hardy plants surviving on ultramafic soils are voluminous, but to date, the actual adaptive relationships between the plants and their environment are vague. California is an excellent place to study these interrelationships because of its quite varied plant life—over 5,000 plant species grow in the Golden State, more than the combined total of the central and eastern United States and adjacent parts of Canada. Additionally, 30% of California’s flora occur nowhere else in the world. By comparison, only 13% of the flora in the Northeastern U.S. are endemic, and only 1% in the British Isles. One reason for California’s prolific flora is its remarkably varied habitats. The latter provide conditions for a plant’s successful survival and reproduction. California has a multitude of climatic conditions as well as a wide variety of rock types to support its complex floral communities. Similar habitats have been grouped into landform provinces based on their comparable topographic and climatic conditions. Each province, however, often contains a diversity of unique habitats, in large part a result of California’s complex and active geological processes. Landscape evolution and the accompanying cooler, drier climate, for instance, gradually transformed some of the Tertiary sub-tropical habitats in central and southern California into semi-arid and desert communities. Lush forests were restricted to the wetter areas along the temperate northern California coast. Subsequent uplift of the Sierra Nevada range provided wet, higher elevation habitats on its western slopes and parched deserts in the rain-shadow to the east. Glacial-induced climate fluctuations yielded even more microenvironments that survived in sheltered areas until today. Other important factors influencing a plant’s survival include its ability to interact with other plant species, compete with them for nutrients, protect itself from indigenous fauna, and successfully reproduce. All of these geological changes drove evolutionary mechanisms to fill the new habitats, as existing species were forced to occupy restricted habitats called refugia. California’s tectonic activity and numerous microclimates have heavily influenced plant distribution in the state. Some restricted habitats are disappearing while others are emerging, but both support rare plant species. Isolated seasonal habitats likewise spawn unusual flora, often differing from one location to another. Unique habitats often occur as “islands” surrounded by more common vegetation. Many of these isolated ecological communities exist because of the local geology. Complex intermixtures of rock types provide very distinctive soils that are home to rare plant life. Because they lack many key elements that support the usual floral species, and are enriched in harmful elements, serpentine soils are home to a variety of uniquely adapted plants. The soils are rich in heavy metals and barren of vital elements needed to support conventional plant life. They are shallow, low in calcium, high in magnesium, and do not hold water well. Serpentine flora provide an exciting opportunity for botanists and ecologists to probe adaptive evolutionary mechanisms. The soils that develop on these ultramafic rocks contain some elements, like nickel and chrome, which are toxic to most plant species. The stresses induced by their extreme compositional characteristics have actually selected traits and mutations that allow certain hardy plants to adapt to serpentine soils. Some plants actually become tolerant to these toxic elements and are capable of assimilating large quantities without ill effects, a phenomenon known as hyperaccumulation. Mutation may play a role in this adaptive process. Cheryl’s thesis study was conducted in a very remote part of the Six River National Forest in Del Norte County. Her field area was located on the Josephine ophiolite atop serpentine and ultramafic rocks. The area is isolated and inhabited by a very private rural population, wary of strangers. Cheryl needed to exercise caution as she hiked the backcountry with her trusty dog in search of Arabis macdonaldiana colonies. Serpentine chaparral interspersed with evergreen woodlands dominate the rugged landscape. The tiny magenta flowers hug the ground and are unobtrusive except in localized colonies where they form thick carpets. Cheryl sampled the soils around the plants, being careful not to disturb them. The samples were used to determine the soil mineralogy and its elemental composition. Another element in high concentration at the plant sites is barium. Adaptation to the toxic influences of barium may be a key factor for flora that exist on serpentine soils. Toxins and growth inhibitors drive natural selection by favoring certain mutations. Some of these selective processes may involve changes in only a single gene. Cheryl’s studies, though not conclusive, have provided trace element data that can be used to further characterize the environmental effects surrounding Arabis macdonaldiana . Audience discussion following the talk mentioned the pioneering work of California botanist Arthur Kruckeberg on serpentine flora. He summarized his studies in his 1984 publication California Serpentines: Flora, Vegetation, Geology, Soils, and Management Problems . This treatise, and additional research being conducted at the U.C. Davis McLaughlin Reserve in the California Coast Range north of the Napa Valley, have made significant contributions to understanding the mechanisms that control the state’s diverse vegetation. Kruckeberg echoes many of the reasons mentioned above that make serpentine soils so infertile: their high magnesium, nickel, and chromium contents, low levels of soluble calcium and nitrogen, and poor water retention. Included in the “serpentine” category are soils derived from partially serpentinized peridotite (an ultramafic rock), gabbro (the plutonic equivalent of basalt), and basalt greenstones (metabasalts of ophiolitic origin). All these soil derivatives share similar soil characteristics with the serpentinites and also support unusual plant life. Kruckeberg described plant responses to serpentine soils as avoidance, indifference, and endemism. Indigenous taxa that cannot survive on serpentine substrates are the avoiders; the flora that can endure both serpentine and nonserpentine soils are indifferent; and the endemic species are restricted to serpentine soils. It is the latter (endemic) species that have caught the eye of evolutionary biologists. Theories regarding the origin of the endemics are twofold. One champions the paleoendemic hypothesis, which propose that ancestral species occupied several habitats until climate changes caused extinction of the nonserpentine populations. The other is the neoendemic theory, which suggests the “insular” taxa with extremely limited ranges evolved from ancestors living on adjacent nonserpentine soils. Botanists have shown that the endemics will grow on nonserpentine soils if carefully nurtured, and that they will flourish there if cultivated alone. This would imply that competition with other species on the nonserpentine substrates forced them to occupy the more harsh conditions of the serpentine soils. The degree of plant endemism is also variable, from 100% serpentine restriction to only partial restriction, depending on the local geology. Reduced restriction is exhibited by “indicator” taxa, which are serpentine-restricted in only part of their ranges. Kruckeberg estimated an approximately equal count of serpentine endemic and serpentine indicator species, totaling over 425 taxa. He also noted that the Northern Coast Range serpentinites are particularly rich in plant life. Continuing serpentine flora research is being conducted at the McLaughlin Reserve, and is methodically revealing the survival strategies of these unusual plants. The NCGS gratefully acknowledges Cheryl Smith for sharing her research on the major and trace element geochemistry of serpentine soils and its potential impact on the endangered plant Arabis macdonaldiana (McDonald’s rock cress). The botanical research surrounding this and other endemic serpentine soil inhabitants is making major contributions to evolutionary biology. However, the soil mineralogy and elemental chemistry, as pointed out by Cheryl, needs further clarification to identify its specific role in the survival of these hardy plants. Note: The biological commentary on serpentine floral species and their evolutionary development was taken from the McLaughlin Reserve website, and from a short article called Why Rare Species? authored by Susan Cochrane and posted on the Ceres website. BACK TO LIST

Wildflower Mount Diablo Notch Leaf Clover Scientific Name: Trifolium bifidum Family: Fabaceae (Pea Family) Blooms: Color: Red-Pink Annual herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants