Wildflower Mount Diablo Serpentine Collomia Scientific Name: Collomia diversifolia Family: Polemoniaceae (Phlox Familiy) Blooms: May - June Color: Red-Pink Annual herb Native This plant is rare in Mount Diablo State Park. See full list Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Steven Beatty

Wildflower Mount Diablo Milk Thistle Invasive, naturalized Scientific Name: Silybum marianum Family: Asteraceae (Sunflower Family) Blooms: Jun Color: Blue-Purple Annual or perennial herb Introduced Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring

Wildflower Mount Diablo Mountain Mahogany Scientific Name: Cercocarpus betuloides var. betuloides Family: Rosaceae (Rose Family) Blooms: Apr Color: Yellow-Orange Tree or shrub Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Kevin Hintsa

Pacific Digger Bee Anthophora pacifica Apidae Anthophora Describe your image Describe your image Describe your image Describe your image Describe your image Describe your image Description Anthophora pacifica female bees are all dark in color, with dark hairs, except they have white scopal hairs on the hind legs (a nice contrast). Their abdomens are dark and often have a bluish tinge (much like Anthophora edwardsii ) and the abdomen lacks distinct white banding. A distinguishing feature in male bees is the presence of long fringes of white hair on the middle tarsi (mid-leg - see photo above-left), and on the abdomen they have white hairs on tergum 1 and tergum 2, and black hairs on tergum 3 and tergum 4. Males have yellow patches on the face (clypeus and labrum), while females do not. Photos shown here are of males (still searching for female). Nectar/ Pollen Plants This bee is a nectar and pollen generalist. It has been seen on Mount Diablo on manzanita flowers. Habits These digger bees are ground nesters and they can nest in large clusters. This bee overwinters as an adult in its nest cell (unlike most bees, which overwinter as prepupae). Season February and March - not common.

Wildflower Mount Diablo Sticky Mouse-eared Chickweed Scientific Name: Cerastium glomeratum Family: Caryophyllaceae (Pink Family) Blooms: Mar - Jun Color: White Annual herb Introduced Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring

Myths of Mount Diablo by Naturalist Michael Marchiano The "Deadly Big Four" October 1, 1998 Tarantula | Debbie McKeown Mount Diablo is home to an array of many extraordinary plants, animals, habitats, geological formations, and mico-environments. Rarely seen animals as large as a mountain lion, as elusive as a night snake, and as fleeting as a Ceanothus Moth are not seen by the average visitor or casual hiker. Among this fabulous fauna are four creatures that have come to notoriety through folk lore, mythology, and undeserved bias. First and foremost on this list is the California Tarantula (Aphonopelma iodus ). Many visitors to the park are surprised to discover that tarantulas reside here at all. Those that visit the mountain in late summer and early fall (mating season for these benign giants) often see the males crossing a road or path looking for a female in her burrow. Contrary to popular belief, these gentle arachnids are completely harmless to humans. Actually, there is NO tarantula known world wide that is deadly to man. There are a few African and Asian species that have a painful bite, but no one has ever died from a tarantula bite. People often compare a tarantula bite to a bee sting. However, this is absolutely false. Having experienced both, I would allow ten tarantulas to bite me before allowing one bee to sting me. Bee stings are very painful, burn, cause swelling, and last for two to three days. Tarantula bites do none of these. These magnificent and slow-moving spiders, although commonly portrayed as threatening, dangerous, and monstrous in the media and movies, are none of the above and have been unjustly vilified. Another creature with an undeserved reputation is our local scorpion. Most visitors never see or come in contact with scorpions and actually are quite surprised when they find out we have at least three species living on Mount Diablo. The most common is the California Forest Scorpion (Uroctonus mordax ). Growing up to two inches long, it is the largest in the area. Once again, its ability to inflict a “deadly” sting is a complete fabrication. NONE of the three local species can inflict a sting of any consequence to a human being. The forest scorpion sting feels like a mild burning sensation and lasts for no more that 15 minutes, usually less. The only way to get stung is to grab or step on a scorpion barefoot. Scorpions only come out at night to hunt for other scorpions, insects, and small arthropods. If you wish to see these fascinating creatures, join one of our summer night hikes and you will be surprise when we use an ultra-violet flashlight to locate them and cause them to glow in the dark. Next on our list of the feared and “deadly” is the only spider of any medical significance in Contra Costa County, the “notorious” Western Black Widow (Lactrodectus hesperus ). This shiny black spider with a red hourglass shape on its underside is ubiquitous through out Contra Costa County and can be located on Mount Diablo around any campground, building, out house, or wood pile. It is another night time hunter, staying well hidden near its web during the day and then pouncing on unsuspecting insects that get too close to its web at night. It likes dark, undisturbed places. Once again, the Black Widow's bite is way overrated. Although its venom is very toxic, it has such a small quantity that often its bite has no or only mild effects on a person. In severe cases, maybe involving a child or an immune-compromised individual, the venom can cause pain, red lines extending from the bite, and flu like symptoms such as achy muscles, headache, and nausea. Rarely is anti-venom used because it commonly can cause anaphylactic shock, which causes death more often than the bite itself. In the past 37 years, the CDC does not have a record of one confirmed death from a Black Widow in over 50,000 reported incidents each year in the United States. Like each of the above, these beneficial creatures just want to be left alone and rightly fear us far more than we should ever fear them. The last of our “Big Four” creatures of “death” is the Northern Pacific Rattlesnake (Crotalus oreganus ), the ONLY venomous snake in Northern California. Once again, this is a non-aggressive creature who wishes to avoid contact with humans. We have very few bites here on Mount Diablo, especially considering that this is one of our most common snakes. Most bites are caused when someone reaches for the snake (not a bright idea) or on a rare occasion when someone steps on a snake inadvertently. The bite of this animal should always be considered serious and checked out medically. Although there are very few deaths caused by venomous snakes in the United States, there is plenty of serous pain, suffering, and other temporary discomfort from a bite. Once again, the actual numbers undermine the deadly reputation of this fascinating serpent. Out of approximately 10,000 venomous snake bites annually in the United States, there are only 10-12 deaths, half of which are from members of religious cults who handle deadly snakes and will not seek medical attention if bitten. Rattlesnakes as well as several other local snakes help to keep rodent populations in check and in turn become food for larger predators. They are an integral part of our Mount Diablo ecosystem. Each of the above creatures has its place in the natural order. When you learn about their fascinating lives and their relationship to the rest of the environment, you will no longer fear these animals but instead respect them. Western Forest Scorpion (Uroctonus mordax) Dan Sandri Western Black Widow | Michael Marchiano Northern Pacific Rattlesnake | Michael Marchiano Scorpion | Denise Wight BACK TO LIST

Wildflower Mount Diablo Brewer’s Ragwort Scientific Name: Packera breweri Family: Asteraceae (Sunflower Family) Blooms: Apr-May Color: Yellow-Orange Perennial herb Native, endemic to California Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Steve Beatty

Most Excellent Spring Hike by Steve Smith Camels, Sunsets, and Buckeyes March 28, 2025 Steve Smith It is wildflower season on Mount Diablo and the hike of the month will explore some of our best single-track trails with some explosions of color. This hike can be modified to begin from just about any trail entrance, this version begins from North Gate Road where Burma Road crosses over, there are a dozen or so parking spaces in this area. You can just as easily begin from Castle Rock Park in Walnut Creek or Macedo Ranch in Alamo. The hike here is 5.7 miles and 1,000 feet of climbing...but you should allow lots of time to enjoy the beauty along these trails. Of course a nice sunny day is best for maximum color impact. Don't wait too long though, as the non-native grasses grow taller and taller, the poppies and other low-growing flowers tend to get swallowed up. North Gate Road is well-known for Mount Diablo's version of a superbloom, and right now the Poppies and Lupine are abundant and spectacular. Park where Burma Road crosses North Gate and head uphill on Burma, making your first left on Camel Rock Trail. You are going to explore this trail for 1.6 miles and will find many lovely flowers as well as several mini-waterfalls and fabulous rock outcrops along the way. Arroyo Lupines line the hillsides but you'll also find Fremont Star Lily, Blue Dicks, Blue Witch, and of course fields of Poppies. At trail's end you will cross back over North Gate and down Little Pine Creek trail. Make your first right and begin your climb up Falcon Road. This area is beginning to pop with color, take note of the varying colors of green as the Oak trees and Buckeyes continue to leaf out. You may be greeted with some pops of yellow Mule Ears along the way. Keep your eye out as you get closer to the top for the Wood Spirit guarding the trail. Turn right on Sunset Trail ensuring you learn a little about our Peregrine Falcons at the interpretive panel...Castle Rock is off limits this time of year for nesting. Sunset Trail is a lovely winding path down the hillside with lots of "smalls", flowers less than the size of a dime. However, keep an eye out for our iconic and endemic Mount Diablo Globe Lily...they are just starting to pop up throughout the park and along here in early April. Once you reach trail's end, hang a left on Stage Road. This is the original stagecoach route which once brought visitors from the train station in Martinez up to the Mountain House Hotel in the late 19th century. Beware this time of year as you will be crossing Pine Creek half a dozen times or more as you soak up the sounds (and perhaps the water) of a babbling brook and the lush riparian corridor. You will be traveling this relatively flat trail for about a mile before you veer to the left as Stage Road begins to climb back up the hill. Look out for carpets of Fiddlenecks and Blue Dicks before making a left on Buckeye Trail. Here you are treated to lush grasses and some small waterfalls...keep your eye out on the right for our showiest of flowers, Mule Ears. As you begin to glimpse the hills beyond you should start seeing hillsides of Poppies, particularly the area above and below the North Gate Road washout. Arroyo Lupine are abundant as well in addition to Mustard and Wild Radish. Continue on this lovely trail for a total of 1.2 miles until you reach Burma Road again, a quick right will bring you back to your car. C heck out our Wildflower Bloom Report and take it along with you to see how many you can find along the way! Wood Spirit Fiddleneck Mule Ears Arroyo Lupine Camels-Buckeyes BACK TO LIST

Turkey Vulture Diurnal Birds of Prey Turkey Vulture Carthartes aura All Year Diurnal Birds of Prey Daniel Fitzgerald Found in open woodlands, or in open country near cliffs or forested areas. In-flight, comparatively long tail and two-toned coloration to underside of wings distinguish this species. Featherless head is red. When flying, wings are held in a slightly upward position, creating a ‘V-shaped’ or dihedral appearance. Typically nests in the base of hollow trees or tree stumps, or on cave floors or cliff ledges. Generally no nest materials are used. Feeds on a diverse array of carrion of both wild and domestic origin, with mammals being most common.

Rufous Hummingbird Hummingbirds Rufous Hummingbird Selasphorus rufus Migrating Hummingbirds Daniel Fitzgerald The adult male has a rufous back and tail and bright orange-red throat. The adult female and immature birds have a green back and dull rufous sides and at the base of the tail.

Grassland American Crow Corvus brachyrhynchos American Kestrel Falco sparverius American Pipit Anthus rubescens American Robin Turdus migratorius Band-tailed Pigeon Patagioenas fasciata Barn Owl Tyto alba Barn Swallow Hirundo rustica Black Phoebe Sayornis nigricans Brewer's Blackbird Euphagus cyanocephalus Brown-headed Cowbird Molothrus ater Bullok's Oriole Icterus bullockii Burrowing Owl Athene cunicularia Calliope Hummingbird Selasphorus calliope Cedar Waxwing Bombycilla cedrorum Chipping Sparrow Spizella passerina Cliff Swallow Petrochelidon pyrrhonota Common Raven Corvus corax Cooper's Hawk Accipiter copperii Eurasian Collared-Dove Streptopelia decaocto European Starling Sturnus vulgaris Fox Sparrow Passerella iliaca Gambel's White-crowned Sparrow Zonotrichia leucophrys gambelii Golden Eagle Aquila chrysaetos Golden-crowned Sparrow Zonotrichia atricapilla Great Horned Owl Bubo virginianus Horned Lark Eremophila alpestris House Finch Haemorhous mexicanus House Sparrow Passer domesticus Killdeer Charadrius vociferus Lark Sparrow Chondestes grammacus Loggerhead Shrike Lanius ludovicianus Mourning Dove Zenaida macroura Northern Harrier Circus hudsonius Northern Mockingbird Mimus polyglottos Phainopepla Phainopepla nitens Purple Finch Haemorhous purpureus Red-shouldered Hawk Buteo lineatus Red-tailed Hawk Buteo jamaicensis Red-winged Blackbird Agelaius phoeniceus Rock Pigeon Columba livia Rock Wren Salpinctes obsoletus Savannah Sparrow Passerculus sandwichensis Say's Phoebe Sayornis saya Sharp-shinned Hawk Accipiter striatus Song Sparrow Melospiza melodia Swainson's Thrush Catharus minimus Tree Swallow Tachycineta bicolor Violet-green Swallow Tachycineta thalassina Western Bluebird Sialia mexicana Western Kingbird Tyrannus verticalis Western Meadowlark Sturnella neglecta White-crowned Sparrow Zonotrichia leucophrys White-tailed Kite Elanus leucurus Wild Turkey Meleagris gallopavo

Mournful Duskywing Erynnis tristis Hesperiidae Skippers Flies January to October Host Plant Oak Nectar Plant Daniel Fitzgerald Male Michael Marchiano Male Daniel Fitzgerald Underwing