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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

Wildflower Mount Diablo Hopbush, Western Hoptree Scientific Name: Ptelea crenulata Family: Rutaceae Blooms: Mar - May Color: White Tree or shrub Native, endemic to California Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Kevin Hintsa

Wildflower Mount Diablo California Ash, Foothill Ash Scientific Name: Fraxinus dipetala Family: Oleaceae Blooms: Mar-Jun Color: White Tree or Shrub Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Steven Beatty

Wildflower Mount Diablo Venus Thistle Scientific Name: Cirsium occidentale venustum Family: Asteraceae (Sunflower Family) Blooms: May-Jul Color: Red-Pink Perennial herb Native, endemic to California Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants

Wildflower Mount Diablo Coast Silk Tassel, Silk Tassel Bush Scientific Name: Garrya elliptica Family: Garryaceae (Silk Tassel Family) Blooms: Mar Color: White Tree or shrub Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring

Wildflower Mount Diablo Yellow Mariposa Lily Scientific Name: Calochortus luteus Family: Liliaceae (Lily Family) Blooms: Mar - May Color: Yellow-Orange Perennial herb Native, endemic to California Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring

Mount Diablo Western Toad by Joyce Gross A Preliminary Survey April 1, 1998 By Chris Brown, US Geological Survey, Western Ecological Research Center - San Diego Field Station [Public domain], via Wikimedia Commons In April 1998 I photographed Bufo boreas (western toads) breeding and laying eggs in Little Pine Creek. Of the approximately 20 toads present, females predominated. My previous experience observing amphibian breeding congregations indicated that this was unusual--normally there are more males than females--but I didn't realize how unusual until Bruce Waldman, a herpetologist at the University of Canterbury, New Zealand, saw my photos. Bruce also pointed out that many of the eggs I had photographed were irregularly shaped and not viable, probably "old" eggs, ovulated a week or more prior to actual oviposition. Bruce and I monitored Little Pine Creek in the spring of 1999. Toads always return to the same locations to breed. However, we saw no evidence of reproductive behavior. We found no toads, no eggs, and no tadpoles. Amphibian population declines have been occurring with alarming frequency all over the world during the past few years. There are many possible causes, including pathogenic organisms (e.g. chytrid fungi), high UV-B radiation, exotic predators, and habitat destruction. One of the least understood possible causes is pollution by pesticides, herbicides, and residues of commercial plastics. These compounds are similar in chemical structure to estrogen and other reproductive hormones. Thus it is feared that even at very low concentrations, which may pose no toxicological risk to organisms, these chemicals may mimic female hormones and disrupt normal endocrinological processes. The result might be altered reproductive timing that could contribute to reproductive failure. Of course in this case the reasons for our observations may be completely unrelated to the causes about which we are speculating. In 2000, we received a permit from the park to study the toads and test a few if we found evidence of reproductive abnormalities. I visited the park twice a week from February through June. I found normal breeding activity, resulting in small toadlets by June, in two locations in the park: two miles away at the pond off the Bruce Lee trail in Mitchell Canyon, and two miles in the other direction in a cattle pond near China Wall. At Little Pine Creek there was once again no evidence of reproductive behavior. I found two juvenile toads, but no adult toads in or near the creek, and no eggs and no tadpoles. What happened to the adult toads in the vicinity of Little Pine Creek in Mt Diablo State Park remains a mystery. http://amphibiaweb.org BACK TO LIST

Wildflower Mount Diablo Streambank Springbeauty Scientific Name: Claytonia parviflora ssp. parviflora Family: Montiaceae (Spring Beauty Family) Blooms: March Color: White Annual herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Daniel Fitzgerald Flower detail Daniel Fitzgerald Full plant Daniel Fitzgerald

Tarantula Time by Ken Lavin Fall is Tarantula Time on Mount Diablo October 1, 1998 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

Wildflower Mount Diablo Bermuda-buttercup, Sourgrass Invasive Scientific Name: Oxalis pes-caprae Family: Oxalidaceae Blooms: Mar - May Color: Yellow-Orange Perennial herb Introduced Non-native; bigger flower than Yellow Oxalis Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring

California Red Legged Frog by Michael Marchiano April 1, 1998 Michael Marchiano The Calaveras Jumping Frog is a story written by Mark Twain in the 19th century. Contrary to popular belief, the frog in that story was NOT an American Bullfrog but rather California’s largest native, the California Red Legged Frog. The Bull frog (a non-native species) was not introduced to California until the turn of the 20th Century. The Red legged frog, is a species in decline at this time due to habitat destruction (75 % of its historical range altered), fragmentation of its environment, water pollution, pesticides, mining, fertilizers, and the introduction of the bullfrog which eats red legged frogs and tadpoles as well as its food sources. The Red legged frog can grow up to five plus inches (half the size of a bullfrog) and lives up to 8-10 years. The frogs are reddish brown, olive, or gray with black spots. The legs have a dark banding and a dark mask like steak runs from the shoulder to the front of the upper jaw. Normally found near water it will often sit on the bank blending in to its surroundings. It will use its powerful hind legs to leap into the water when threatened or attacked by a predator.It takes two to three years to reach breeding age. Breeding takes place from December to March in seasonal ponds, streams, stock pools, and reservoirs. The female can lay up to 2000 eggs but only about one percent will metamorphosis into frogs. Tadpoles mature into frogs in three to seven months, often depending on the availability of water. Water sources with shore line growth of willows or cattails are ideal breeding locations, providing hiding place. In drought years many ponds that start out with breeding populations will dry up before metamorphosis is completed. Although a riparian frog, it is capable of traveling several miles overland in rainy weather. During dry spells it often seeks refuge in leaf litter, animal burrows (especially ground squirrels and gophers) and under fallen trees. They must stay cool or wet enough so as not to dry out. Predators consist of the afore mention introduced American bullfrog, cats, garter snakes, raccoons, foxes, coyotes, egrets, bass, and introduced mosquito fish eat their eggs and newly hatched larva. Their food consists primarily of insects and other invertebrates but they have been known to eat tree frogs and small mice when available. This very attractive amphibian is now protected under both State and federal law as a threatened species. Several populations of red legged frogs breed in Mount Diablo State Park but with our current drought situation many of their breeding sites are drying up before the frogs reach maturity thus causing a decline in their population. by Michael Marchiano by Michael Marchiano BACK TO LIST

Wildflower Mount Diablo California Milkweed Scientific Name: Asclepias californica Family: Apocynaceae (Dogbane Family) Blooms: Apr - May Color: Red-Pink Perennial herb Native Toxicity: minor, dermatitis. Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring