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Clark's Sphinx Moth by Dan Sandri Who thought a moth could look so cool! 2025-03-20 Dan Sandri Try to focus on that green blur in front of a blossom, perhaps a Blue Dicks flower (Dichelostemma capitatum ) or vetch (Genus Vicia ). Is it a hummingbird? Perhaps. But it may be a Clark’s Sphinx moth too! This time of the year (from March to June), they are flying about the oak woodland and surrounding grasslands from flower to flower, drinking flower nectar from a variety of flowers. It moves so quickly to another flower, uncurling its long proboscis to reach into flowers. They are not abundant, but I see them nearly every year. Clark’s Sphinx moths have a greenish forewing and an orange hindwing that has a black band along its base. Clark’s Sphinx range from Baja California north to British Columbia, and east to Idaho, Wyoming and Utah, and can be found in Oak woodland foothills. They lay eggs on Elegant Clarkia (Clarkia unguiculata ), the sole host plant that their caterpillars feed on. The eggs hatch in about 10 days, and once fully grown, the caterpillars pupate in burrows dug under rocks or other objects. They overwinter there and emerge the following Spring. I hope you see one! Clark's Sphinx Moth BACK TO LIST

Rugged Plants Contributed by Dan Day Reprinted by permission from the Northern California Geological Society Newsletter A Struggle to Survive on Barren Serpentine Soil 1999-01-01 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

Northern Pacific Rattlesnake by Michael Marchiano 1998-10-01 Michael Marchiano Ever since the story of Adam and Eve, western culture has had an aversion to snakes. The fact that a few species are venomous just adds more fear. In Northern California, there is only ONE venomous species of snake, the Northern Pacific Rattlesnakes (Crotalus oreganus oreganus ). All other snakes in the Bay Area are harmless. Our local rattlesnake is very distinctive from other local snakes because of the rattle attached to its tail and the diamond-shaped head that is far wider than its neck. Its coloration can vary, matching its environment. When young, its blotchy pattern is generally much more distinct, fading as the snake ages. Color can vary from drab olive green, to dusty brown, reddish brown, grey, or golden with the darker irregular blotching along the length. When encountered, this snake is not aggressive and either freezes so as not to draw attention to itself or flees, trying to escape any confrontation. Like any wild animal, it will attempt to defend itself when molested or attacked. This is when people see it in its most often portrayed position of coiled, tail rattling its warning, and head held high to observe its attacker. Like all snakes, rattlesnakes do not attack people. The venom they possess is for the purpose of killing small prey animals and they do not want to waste it on a two- legged predator. There are many, many myths and exaggerations concerning snakes in general, but there are even more concerning rattlesnakes. The Northern Pacific Rattlesnake rarely grows more than 36 inches in length - one over 48 inches is a real granddaddy, yet I commonly have people tell me stories of the 6- to 7-foot rattlesnakes they have encountered in the Bay Area (fear and imagination go together). The actual striking distance for a snake from a coiled position is approximately a third the distance of its body length, but let’s give the snake the benefit of half the distance, just to be safe. That means a three-foot snake can only strike out approximately 1-1.5 feet. You would have to be right in that snake's face to get him to strike. They do not strike without reason. Leave the snake alone and he will leave you alone. In late summer to early fall, we enter the birthing season for snakes. Rattlesnakes are one of the few live-bearing snakes (opposed to egg-lying). Mother rattlesnakes can give birth to 7-15 young who actually stay with her for the first couple of weeks. The young are distinctly patterned replicas of the adult except they initially have a single button on their tail. They will not get a second rattle until they shed their skin for the first time, generally within a few weeks. Rattlesnakes get a new rattle every time they shed and may shed three to four times in the same year. Therefore, the number of rattles does not tell the age of the snake. Secondly, as the snakes age, rattles will commonly break off. Young rattlesnakes possess venom when they are born - it is the same venom as the adults, just less of it. The bite of a small rattlesnake is NOT more venomous than an adult, but adult rattlesnakes have been known to give a dry bite (no venom), 30 to 40 percent of the time. The young snakes are still learning to control envenomation and therefore do inject venom with each bite. Nevertheless, any bite from a rattlesnake needs immediate medical attention. Although death from a bite is very rare (in the United States, 10-12 deaths from venomous snakebites occur annually per 10,000 bites), hospitalization with severe pain and suffering is the norm. Rattlesnakes, along with all other snakes, fill an important ecological niche and should not be killed. They eat numerous rodents and in turn are attacked and eaten by larger predators, including hawks, eagles, owls, bobcats, and coyotes. As a rule of thumb, do not try to touch, capture, pick up, or tease any wildlife. Even a cute little cottontail rabbit will bite and claw to defend itself if confronted. Northern Pacific Rattlesnake | Clayton Worsdel by Scott Hein BACK TO LIST

MDIA Turns 50! Steve Smith, MDIA President 1974 - 2024 2024-01-01 The Mount Diablo Interpretive Association is celebrating a huge milestone this year, our 50th Anniversary! MDIA was the brainchild of Sam Smoker, Executive Director of the Lindsay Museum in Walnut Creek, who formulated a vision of an interpretive association that would supplement, in a significant way, the work of the small staff of rangers at the ever-expanding Mount Diablo State Park. Smoker recognized the need for a wider public appreciation of this great natural treasure that exists within an area of rapid urban expansion and concurrent loss of the original environment. The task was interpretive; the key was education. A meeting convened on the proverbial dark and stormy night of January 30, 1974 in Smoker's living room. Among those present were Mary Bowerman, founder of Save Mount Diablo and preeminent botanist; Frank Valle-Riestra, a scientist with an interest in natural history; Ron Edwards, a wildlife expert from the Lindsay Museum; Phil Gordon, biology teacher, and ornithologist associated with the Audubon Society; Beverly Clemson, Director of the Shadelands Ranch Historical Museum; Howard Knight, Professor of Biological Sciences at Diablo Valley College; Betty Zilen, retired Mount Diablo School District science supervisor; and Ed Earl, Superintendent of Mount Diablo State Park. MDIA continues its long-standing mission of Preservation through Education and has remained an all-volunteer non-profit cooperating association benefiting Mount Diablo State Park. BACK TO LIST

Tarantula Time by Ken Lavin Fall is Tarantula Time on Mount Diablo 1998-10-01 Ken Lavin Autumn is a delightful time to hike the golden hills of Mount Diablo. But unsuspecting hikers are often startled to find themselves sharing the trails with some rather formidable eight legged walking companions! "What are the critters doing?" "Where are they going?" "Will they hurt me?" These are the common questions park staff and park volunteers must answer this time of year. Fall is tarantula time on Mount Diablo. Mount Diablo's tarantulas (Aphonopelma sp.) have long inspired fear and fascination. One 19th century visitor described our local tarantula as "attaining the size of a small bird, possessing fangs the size of a rattlesnake's, and delivering a bite generally considered fatal!" In reality, the tarantula is one of Mount Diablo’s most innocuous animals—a terror to small insects and not much else! Outside of horror movies, no person has ever been killed by a tarantula. Tarantulas have very small venom glands and the bite of our local tarantula is no more painful that a bee sting. Harmful spider bites generally come from poisonous spiders that are too small to notice. The tarantula, being so conspicuous, gets the blame. For example, in Renaissance Italy, the bite of a tarantula was thought to cause convulsions. The only known treatment was to sweat the poison out by frenetic dancing. This was the origin of the tarantella, the dance named for a spider! In reality, a European black widow, and not the innocent tarantula, was the culprit doing the biting. The tarantula's main weapon against larger creatures is defensive. If a bobcat or fox is harassing it, the spider rises up on its front legs and with its back legs scrapes off a cloud of barbed, porcupine-like hairs from its abdomen into the face of its tormentor. This tactic sometimes gives the tarantula time to escape. It also gives rise to another common visitor query, "Why does that tarantula have a bald butt?" Although most commonly seen wandering the roads and trails in late summer and early fall, tarantulas are on the mountain all year. They are seldom seen at other times because they live in underground burrows and are nocturnal in their habits. Typically, a hunting tarantula waits patiently near the opening to its burrow until an unsuspecting insect (usually a cricket) crawls by. The spider rushes out, bites the prey, and drags its victim back into the burrow. In the dark of night, this activity goes unnoticed (except by the cricket!). This secretive existence ends in late summer, when male tarantulas that have reached about 7 years of age shed their exoskeleton for the last time. They have finished growing. The mature spiders leave their burrows and begin to search for female tarantulas. It is this horde of love struck males, searching for females with which to mate, that forms the annual "tarantula migration" park visitors witness each year in September and October. Male and female tarantulas are difficult to tell apart until the last molt, when the male spider develops little stirrups on its front legs. Why does the tarantula need these strange appendages? When the male finally locates a female tarantula and entices her out of her burrow, her thoughts are not on love but on dinner. In order to safely mate, the male spider must hook and secure the female’s fangs using the stirrups on his front legs. After mating, the male scurries away, and the female usually allows him to leave. It is a myth that female tarantulas always kill the males after mating. A female will consume the male only if she is famished and needs a meal to be able to lay eggs. Otherwise, she allows her paramour to retreat in safety. Though free to live another day, the roving male spider never returns to his burrow. Rather, he wanders around searching for other females until he finally dies with the onset of cold weather. The stay-at-home mother tarantula, by contrast, may live to the ripe old age of 20 years or more. After mating, the female retreats to her burrow and lays about 100 eggs on top a sheet of silk spun from her spinnerets. Momma spider shapes the silken sheet into a basket and guards the eggs inside until they hatch. Soon after hatching, the tiny spiderlings crawl out and leave the burrow. Of the hundred or so eggs laid, perhaps one or two spiders will survive to adulthood. It's not easy being a tarantula. In fall, pesky yellow jacket wasps are the bane of Mount Diablo picnickers. The picnickers should consider themselves lucky, for the wandering tarantula must contend with a far more formidable flying foe. The spider's antagonist is a large black and orange wasp, known as a tarantula hawk (Pepsis sp.) The female wasp flies around searching for a tarantula. When she locates one, the wasp attacks and stings the spider under a leg. This does not kill the tarantula, but it does paralyze him. The wasp drags the spider off, scraps out a hole, and pushes him in. Before she covers the tarantula, the wasp lays a single egg on the helpless spider. When the egg hatches, the wasp larva dines on fresh tarantula meat! For all their fearsome reputation, Mount Diablo’s tarantulas are really gentle souls that play an important part in the web of life on our island mountain. So the next time you encounter a tarantula on the trail, remember the old adage, "if you wish to live and thrive, let a spider run alive!" BACK TO LIST

Early Spring Wildflowers by Kevin Hintsa 1999-01-01 Mount Diablo Manzanita | Kevin Hintsa The winter rains and increasing daylight of early spring triggers a spring bloom for many of Mount Diablo's native wildflowers. The exact timing and quantity of blooming wildflowers will vary greatly year to year as it is controlled by a number of environmental factors. By late February there are a number of flowers to view, especially in the chaparral and at low elevation grassy hilltops. The following include most of the more striking species that one might find in the first three months of the calendar year. Bear Brush (Garrya fremontii ) starts off the new year in a bizarre manner by blooming in early January at the summit of Mount Diablo. This uncommon evergreen shrub, resembling the evergreen oaks in both leave and flowers, produces two inch long pale lavender catkins on the male shrubs. Blooming may be triggered by the increasing daylight as it often blooms in icy conditions. The more common Coast Silk-tassel (Garrya elliptical is easily found between Curry Point and Sycamore Canyon in February and March). Manzanita (Arctostaphylos sp. ) is perhaps the star attraction of December to March. These evergreen shrubs with red bark fill the chaparral (and a few wooded slopes) with delicate white to pink tiny bell-like flowers that attract a great number of insects and the occasional hummingbird. The Mount Diablo Manzanita (Arctostaphylos auriculata ) grows only around Mount Diablo and has the pinkest blossoms of the mountain's manzanita. It is easily seen around Wall Ridge, Live Oak Campground and also between Curry and Knobcone Point. Another early bloomer is Chaparral Currant (Ribes malvaceum ). This deciduous shrub often begins blooming in late December at lower elevations, finishing at the summit around early May. The flowers are pink and are quite striking when seen in mass. It is easily seen around Knobcone Point and along Summit Road. The similar Gooseberry differs in having thorns and smaller flowers. Mitchell Canyon and the summit area are good places to look for it. Warrior's Plume is a semi-parasitic herbaceous plant of chaparral-pine areas. The red green leaves are a pleasant sight in early March along Wall Ridge or Curry to Knobcone Point. It blooms in April at the summit. The newly opened leaves are pure red in this and many other species as a protection against ultra-violet light. Members of the Mustard family are well known early bloomers. Milk Maids (Cardamine californica ) is very common just about everywhere on Mount Diablo, often occurring in heavily shaded forests. Its simple white flowers can be common by mid-February at low elevations, finishing at the Fire Interpretive Trail in May. Our state flower, the California Poppy blooms nearly year round, mostly March to October on Mount Diablo. Its lacy gray-green leaves and golden yellow to orange flowers are well known to most Californians. It is generally found in the grasslands below 3500 feet. Check North Gate Road in mid-April to early May for peak mass bloom. Buck Brush (Ceanothus cuneatus ) is an evergreen shrub that is fire dependent, as it gets crowded out in older stands of chaparral. Its mass of white blossoms (smelling like popcorn) starts in early February along lower South Gate Road, finishing in May at the Fire Interpretive Trail. Jim Brush (Ceanothus oliganthus ) is another of the so-called California Lilacsi. It has powder blue blossoms and blooms from late March through May, more commonly on the north side of the mountain. Very pleasing to the eye in early March is Johnny-Jump-Up (Viola-pedunculata ). These are golden yellow with black markings and have a striking reddish brown underside. Look for it a Curry Point. Much smaller and more widespread on the mountain is the similar looking Mountain Voilet (Viola purpurea ), blooming March to May. It is fairly common in the area around the Summit. Brewer's Rock Cress (Arabis Breweri ) is found on rock outcrops at 1200 feet to the summit. Its small pale green leaves grow in rock crevices and it has beautiful pink to purple flowers (that later form curved seed pods). The summit area is the best site to study this species, but also look for it at the Falls Trail in Donner Canyon. Mosquito-bills (Dodecatheon hendersonii ) is the common species of Shooting Star around Mount Diablo. The nodding pink flowers are quite adorable, especially when in mass. The leaves are simple and basal. Look for it from mid February through April, especially in Mitchell Canyon where it is very common. Grand Hound's-Tongue is a widespread member of the forget-me-not family on Mount Diablo, most found in wooded areas of light shade. It has foot tall flower stalks with powder blue to violet flowers. It usually is well in bloom by March 1 at lower elevations, and finishes in late April along the Fire Interpretive Trail. Brewer's rockcress | Kevin-Hintsa Warrior's plume | Mike Woodring Milk Maids | Kevin Hintsa California Poppy BACK TO LIST

Visitor Center Status - Mount Diablo Summit Visitor Center Open 7 days/week Hours: 9:30 AM – 4:30 PM One way foot traffic through the Visitor Center to minimize crowding. Enter at ground level and exit on second level. Lower floor (sales), Second floor (exhibit room) and Observatory deck will be open. Face coverings are required for all indoors regardless of vaccination status. Mitchell Canyon Visitor Center Open for outdoor operations on weekends and some holidays Hours: 8:00 AM - 4:00 PM The interior remains closed. Operations including sales are currently being done outdoors only. Mitchell Canyon Visitor Center BACK TO LIST

Tarantulas Usher in the Fall Season by Abby Cohn Mount Diablo's Warm-Fuzzy Spiders 1998-10-01 Kevin Hintsa Guess what naturalist Ken Lavin got when he organized a hunt for some big, hairy spiders: A crowd! "I've never been on a tarantula hike before," said Nancy Norland of Danville as she joined nearly 40 participants preparing to scour the brown flanks of Mount Diablo for spiders roughly the size of an orchid corsage. Fall is the time of year when male tarantulas normally scuttle around the hills in search of mates hiding in burrows. The spiders are common enough to warrant the posting of tarantula crossing signs at the north and south entrances of the 20,000-acre state park. Tarantulas have "been scaring folks here for ages," Lavin told the group that had assembled at Mitchell Canyon. But he warned, "This is not particularly a good year." Indeed, during a 3 1/2-hour trek up steep dirt trails to Black Point, the group spotted no tarantulas. Lavin, a guide for the Mount Diablo Interpretive Association, came prepared. He treated his audience to an encounter with a pair of mahogany-colored spiders that he had captured earlier in case there were no sightings. The captives -- they were slowly scaling the walls of their plastic containers -- weren't exactly an instant sensation. A nervous ripple of laughter traveled through the crowd when Lavin suggested that "we can pass these around and hold them" before letting them go. Participants seemed to warm up to the eight-legged guests of honor once they heard Lavin's description of the tarantula's life cycle and mostly gentle disposition. "Oh, he's beautiful," said Norland after letting one of them slowly creep across her hand. "He's so light." For 8-year-old Ryan Neil of Danville, the spider's touch was "furry" and not remotely frightening. "It felt like it was just harmless," he said. Ryan's father, Mike, said the promise of a spider hunt was all it took to snare his son and a friend, 8-year-old Miles Dobin, for the Sunday morning trek. "Even if you haven't been an 8-year-old boy, there's a natural appeal, I think," Neil said. That appeal drew about 400 people earlier this month to an annual tarantula festival at Henry W. Coe State Park in Morgan Hill. A chief goal of the festival was educating the public about creatures that seem to hold a horror, movie-like fascination, said ranger Barry Breckling. There was a similar message for the Mount Diablo hikers. Tarantulas, Lavin explained, have acquired a sinister reputation that is largely undeserved. "It turns out the tarantula is just about the most innocuous creature on Mount Diablo," he said. Sightings of the spiders figured prominently in 19th century accounts of trips up the mountain. A team of geologists returned from a surveying expedition in the early 1860s with wild tales of spiders "the size of small birds," he said. About he same time, copper miners gave whiskey the nickname of "tarantula juice" and claimed the drink was an antidote to the spider's feared bite. In reality, most spider encounters are far riskier for tarantulas than humans, Lavin explained. "They're very delicate," he cautioned as he picked up one of the captives and let it wander on a picnic table. "It's very easy to drop them. They lose their legs." Possessing a bite no worse than a bee sting and generally reluctant to attack, tarantulas often fall victim to the underside of hikers' boots and motorists' tires. They also can be eaten alive if attacked by a nasty parasitic wasp that first paralyzes the spider and then lays eggs on its body. The spider's primary defense: tiny, sharp hairs that it flicks off its abdomen. "I fed these guys," Lavin told his audience. "It took them 15 minutes to kill a cricket. It was kind of embarrassing." He had no explanation for the spider's apparent sparse numbers this fall. Most of the tarantulas roaming around are older males that have molted for the last time and are looking for females buried underground. Perhaps the spider population was reduced by a harsh winter when those males first hatched about seven years ago, Lavin speculated. Male spiders typically 7 to 10 years; females can live to be 20 years old. Dave Matthews, the park's supervising ranger, said he hadn't noticed a particular drop in the tarantula population, but confessed, "I'm not out counting." In hopes of protecting the spiders from being squashed under the tires of passing motorists, rangers last year posted warning signs at two main entrances. "We ask people to watch out for them," said Matthews, who noted that visitors aren't allowed to collect spiders or any other creatures in the park without a special permit like the one Lavin had obtained. While the trek up Mitchell Canyon turned up no tarantulas, the group did spot several burrows. The openings are roughly the size of a nickel and often are covered by a dense netting of web that alerts occupants to the arrival of potential prey -- or suitors. While spiders were the big draw for the morning outing, some hikers acknowledged that they had other reasons for showing up. "I wanted to be out on a Sunday," said Diablo resident Kay Batts, who started the morning playing the organ at a 7:30 Mass. As for the appeal of hunting for tarantulas, she admitted, "I'm more interested in his ladybug hike. " By the end of the trek, a few participants who initially feared spiders thought they'd be a bit more charitable toward tarantulas in the future. "I wouldn't get the broom now," said Carla Riboczi of Concord. "I'd probably let it alone." BACK TO LIST

Living With California Coyotes Reproduced from the California Department of Fish and Game publication 1999-01-01 Coyotes in California Observing wild animals is one of the many benefits of living in or near wildlife habitat. The experience can turn unpleasant or even dangerous, however, when well-meaning people feed wildlife. When fed by people, coyotes can become unnaturally bold and the result is conflict between coyotes and people, which too often ends in serious harm, or even death, to people or the coyotes. The coyote (Canis latrans ), a member of the dog family, is native to California (and Mount Diablo). It closely resembles a small German shepherd dog with the exception of the long snout and bushy, black-tipped tail. The coyote's high-pitched, yodel-like yapping can frequently be heard at night. Coyotes are extremely adaptable and can survive on whatever food is available. They hunt rabbits, mice, birds and other small animals, as well as young deer and sheep. They will also fee on the carcasses of dead animals and will accept "hand-outs" from people in the form of table scraps, pet food and garbage. Coyotes are found throughout California, from desert and mountain habitats to urban areas. Problems occur when people begin feeding coyotes, either deliberately or inadvertently. Coyotes will quickly lose their natural fear of people and become bold,even aggressive. Pets are often attacked, injured or killed by coyotes. In a few tragic cases, coyotes have attacked small children, causing serious injuries and death. Help Keep Coyotes Wild We can reduce conflicts with coyotes by ensuring that they remain cautious of humans. Practice these safety guidelines and encourage your neighbors to do the same. Never Feed a Coyote Deliberately feeding coyotes puts you, your pets and your neighbors at risk. Some communities have ordinances that ban feeding of coyotes or other wildlife. You may be inadvertently feeding coyotes by leaving pet food or garbage where they can get to it. Feed pets indoors or promptly remove outdoor dishes when pets finish their meals. Store bags of pet food indoors. Use trash cans with lids that clamp shut, which will prevent spilling if the cans are tipped over. If you leave garbage outside, don't use trash bags as garbage containers" coyotes can easily rip them open and scatter the contents. Put trash containers out the morning of the scheduled pick-up, rather than the night before. This will give the coyote less time to scavenge. Clear brush and dense weeds from around dwellings to reduce protective cover for coyotes and make the area less attractive to rodents. Coyotes and other predators may be attracted to areas where rodents are concentrated, such as wood and brush piles and seed storage areas. Protect Children Although rare, coyote attacks have seriously injured young children. Never leave small children unattended in areas known to be frequented by coyotes, even in your yard. Protect Pets and Livestock Keep small pets, such as cats, rabbits and small dogs, indoors. Don't allow them to run free at any time. They are easy, favored prey. Some coyotes seek cats in residential areas. Large dogs should be brought inside after dark, and never be allowed to run loose. Rabbit hutches should have a solid bottom. A hutch standing above ground, with only a wire bottom, makes your rabbit an easy mark. When building a chicken coop, dig a one-foot trench around its perimeter. Extend the chicken wire fence well into the trench, then bury it. Use Negative Reinforcement If coyotes begin frequenting your neighborhbood, let them know they're not welcome. Make loud noises, throw rocks, or spray them with a garden hose. For everyone's safety, it is essential that coyotes retain their natural wariness of humans. If coyote problems persist, contact your local city government or county agricultural commissioner for assistance. Report Threats and Attacks Immediately If you see a coyote behaving aggressively or attacking people, contact the nearest office of the California Department of Fish and Game during regular business hours, Monday through Friday, 8:00 a.m. to 5:00 p.m. If an encounter or attack occurs after business hours, call the Department of Fish and Game's 24-hour dispatch center at (916) 445-0045. The Department will take appropriate action. Northern California California Department of Fish & Game Office 530-225-2300 Coyote | Carl Nielson BACK TO LIST

Hard Chaparral by Glenn Keator, Ph. D. (Excerpted from MDIA's book Plants of the East Bay Parks) Plant Communities of Mount Diablo State Park 1999-01-01 Arctostaphylos auriculata | Kevin Hintsa Hard chaparral replaces soft chaparral in hotter, drier inland areas, usually on steep, rocky slopes. (Shrubs favor the summer heat of south facing slopes.) From a distance the dense, tall shrubberies of hard chaparral look like a uniform dark green velvet draped over the mountainsides. Hard chaparral is so named because its component species have stiff, tough, durable leaves that are seldom shed even at the peak of summer's heat. In fact, the main attribute of such leaves is their long tenancy; shrubs do not have to expend valuable water to create a new set of leaves each year should rains be sparse. Leaf design varies as much as the several families and general represented. Manzanitas make stiff ovate leaves that are turned edgewise or vertically to avoid the full brunt of sun -- and some kinds, like big-berry manzanita (Arctostaphylos glauca ), have whitish leaves that reflect away excess light and heat. Chamise (Adenostoma fasiculatum ) uses narrow, needle-like leaves clustered together to conserve water by minimizing surface area exposed to sun. Wild lilacs (ceanothuses) cover their leaves with a thick, waxy covering that makes them shiny. Bush poppy (Dendromecan rigida ) has bluish green leaves held obliquely to reflect away heat and minimize the impact of the fierce summer sun. In addition to their ingeniously designed leaves, chaparral shrubs have deeply probing roots that serve to hold shrubs in place and find sources of deeply hidden water. Roots may also carry on chemical warfare with neighboring shrubs to prevent invasion into their own root zone. Chaparral pea (Pickeringia montana) and ceanothuses have tiny knobs on their roots that house nitrogen-fixing bacteria. As a result, such shrubs can move onto nutrient-poor soils; when they die they may pave the way for other shrubs to move in by releasing these nitrogenous compounds into the soil. Chaparral shrubs grow into nearly impenetrable canopies -- from head high to well over ten feet. The best way to pass through is to crawl beneath the branch canopy as small mammals do. Chaparral has been called the elfin forest in allusion to this dense but short forest-like growth pattern. Link to California Chaparral Field Institute website. Link to Belorussian Translation website BACK TO LIST

California Poppy by Steve Smith The Inside Scoop 2025-03-27 Dan Fitzgerald The California Poppy (Eschscholzia Californica) is our state flower, but you knew that. But did you know that it was named by a German, for an Estonian doctor, sailing on a Russian ship, exploring San Francisco Bay? German botantist and poet Adelbert von Chamisso hopped off the Russian exploration ship Ryurik in 1816 to find the hills of San Francisco gleaming with golden poppies. He collected specimens, named the flower after his friend, Estonian ship's doctor Johann Escholtz and then took those specimens back to Russia. Click here to watch a video of the story told by our own Ken Lavin. BACK TO LIST

A Beautiful Evening to Remember by Michael Marchiano, Naturalist On a Friday in July 1998-07-10 Black Point at Sunset • Ray Mengel As the sun set and a light wind blew through the valley oaks, five of us gathered in the Mitchell Canyon parking lot for a leisurely evening hike. We were greeted by the sounds of field crickets as we crossed the gate. We headed up Mitchell Canyon Road observing and listening to the last birds of the day heading for roosting spots or singing their night-time serenade. An acorn woodpecker was tapping away at the top of one of the “pantry” trees, juncos and a titmouse flitted among the branches of live oaks, blue oaks, and gray pines. Starlings were finishing an insect meal at the top of another snag. A black-headed grosbeak was singing its heart out in one of the oaks, and a turkey vulture soared overhead as many springtime insects buzzed through the air. Most of the spring wildflowers along the trail had disappeared. The wild oat grasses had turned golden in the evening light. The most alluring late spring flowers were the delicate white “lilies” of the wavyleaf soap plant. These appeared to dance on the end of their thread-like stems. In the shaded areas were remnants of elegant clarkia flowers, and Ithuriel’s spear still bloomed among the grasses. What creatures would we see or hear as the sunlight dimmed and the sky darkened? This question would only be answered by what lay ahead of us. As we continued our twilight hike, we turned at the intersection of Mitchell Canyon Road and Black Point Trail and then turned onto Globe Lily Trail. Along the chaparral section of the trail, chemise was in full white bloom, and the pale pink-colored mallow with its light gray-green leaves and stems dotted our way. The trail itself was coming alive with harvester ants, picking up tiny seeds and carrying them into their underground burrows. Along the trail, we found numerous tarantula burrows. As we peered into them using our flashlights, we could see the velvety spider sitting at the entrance of its home waiting for that unsuspecting prey to wander by and become an evening meal. We reached Red Road and, in the dim glow of the darkening sky, bats could be seen swooping overhead, soaring and turning and chasing the hundreds of flying moths, mosquitoes, gnats, lacewings, and other airborne arthropods. Many species of bats inhabit the canyons of Mount Diablo, all of them insectivores. In flight, it is all but impossible to tell one species from another, but at least one of the bats was twice the size of the others, and we believed it to be a big brown bat, one of the largest bats in our area. As the night darkened, I took out a small black light flashlight and shined it into a pile of downed tree branches. There scurrying among the debris was a small scorpion, glowing in the ultraviolet rays. Another tiny night hunter was on the prowl. The pathways were also littered with Eleodes beetles, those slow-moving black stink beetles that point their tail ends up in the air whenever they feel threatened. As we left Red Road and returned to Mitchell Canyon Road to head back, we picked up the bight shining eyes of two other night-time wanderers. Although we could not make out the creatures (except for the eyes, and they disappeared into the heavy brush immediately), we believe the first was a coyote and the second a deer. One more time on the way back I took out my black light as we neared a rocky outcrop, and again we were all pleasantly surprised with at least a half-dozen scorpions glowing among the rocks. On our final approach to the visitor center, we had the pleasure of seeing a western toad hop across our path and a large Jerusalem cricket (potato bug) run in circles on the path after we shined our light on it. Many wonderful sights greeted us on this night-time hike, and yet many we expected eluded us. We did not hear the coyotes howl; we did not hear or see an owl; poorwills did not call; glow worms were not seen; and no snakes were slithering about. Chorus frogs were not heard, and no bobcats were seen. Who knows what will await us next time… Only by completing the adventure will we unlock a tiny bit of Mother Nature’s treasures. We hope to see some new adventures on our next night hike! BACK TO LIST