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articles about plants wildlife spiders mammals insects Articles Filter by Category Select Category Pepsis Tarantula Hawk Has Found Its Prey While most of us “Mount Diablo-philes” have a great love for our local tarantulas, I am also enamored with Tarantula Hawks – those large, magnetic blue-black wasps with the orange wings! July 5, 2025 More Hoverflies Hoverflies are Flies in Disguise June 24, 2025 More Jeweled Spider Flies One of my favorite insects is quite uncommon ... June 20, 2025 More Pollen Wasp It isn’t a pest or a predator - this Pollen Wasp behaves more like a bee... June 20, 2025 More Crab Spider Crab Spiders Use Flower Power May 28, 2025 More Acorn Woodpecker A bird that's nut for acorns! May 21, 2025 More Coyote The barking dog May 21, 2025 More Dragonfly Oh my! What big eyes you have! May 21, 2025 More 1 2 3 4 5 1 ... 1 2 3 4 5 6 7 8 9 10 11 ... 11

Learning From Nature Welcome! Explore some resources and ideas for engaging youth in the wonders of Mount Diablo State Park. View a brief message from Steve Smith, MDIA President Mitchell Canyon Windcaves Sentinel Rock near Rock City Mitchell Canyon 1/10 Get Outside! Plan Your Visit to Mount Diablo 8 Popular Hikes Mitchell Canyon Interpretive Trail Mary Bowerman Interpretive Trail Points of Interest Go on a Scavenger Hunt Bring a Journal What Can You See? Choose the season of your visit to Mount Diablo Winter Spring Summer Fall Learning Resources Themed Content Activities and handouts (pdf) Wild Mount Diablo (Videos) Safety Resources Poison Oak (Leaves of 3) Tick Talk Snakes Live Here Too Park Safety Tips Other Resources Browse the resources from our community partners We want to hear from you Fill out the form below to send us suggestions, questions and feedback. Get In Touch First Name Last Name Email Address Subject Message Thanks for your message! Submit

Webinar Recordings Filter by Topic ( or see most recent ) A Natural Combination: Hunting, Conservation & the Choices We Make Webinar Recording Artist, writer, hunter and naturalist Christopher Reiger makes the case that, while not all hunters are environmentalists and not all environmentalists are hunters, there is a natural overlap that needs to be better understood and appreciated by both hunters and anti-hunters. To see more of Christopher’s artwork: https://www.christopherreiger.art . His work has appeared many times in Bay Nature magazine. Art: The In-Between: Ash-colored Silver Dog Tail, 2023 All About Lichen Webinar Recording Mount Diablo is a bio-diversity hotspot for all kinds of animal and plant life, but what about lichens? Cat Chang will share her interest in the tiny world of these fascinating partnerships of fungi and photobionts. We’ll take a look at what is found in the State Park and the surrounding areas. Bring your lichen questions! American Kestrel Webinar Recording Learn about North America’s smallest falcon, the American Kestrel . This colorful and intelligent raptor can be seen hunting in the open spaces around Mount Diablo. Researchers struggle to explain the steady decline of kestrel populations over the years, thus rallying the help of citizen scientists to raise nest boxes and contribute breeding data for national studies. Brian Richardson will share a deep dive review of this treasured bird of prey, along with nesting activity of local nest boxes. Backcountry First Aid: What to do When You Must Act Now Webinar Recording In 2013, Terrie Arnold, a backcountry hiker extraordinaire, was swept downslope by a rockfall in the Eastern Sierra. Being a registered nurse with 25 years as a specialist in spinal cord injuries, she diagnosed her injury instantly: a lower leg fracture. With the aid of her three hiking companions, she extricated herself from the unstable, steep terrain and now makes it her mission to teach hikers at all levels about backcountry first aid. In this presentation, she inspires us all to learn how to respond when an emergency situation occurs in the backcountry. Birds of Mount Diablo Webinar Recording Birding and bird photography enthusiast Jerry Britten will present a slideshow of Birds of Mount Diablo. Far from an exhaustive overview, he will focus instead on a subset of birds including hummingbirds, spring warblers, some uncommon birds and some ID challenges. His presentation will feature sound recordings as well as photographs. Jerry is the President of Mount Diablo Audubon Society, and a volunteer property monitoring steward and hike leader for Save Mount Diablo. He has seen over 1500 species of birds, and photographed over 1100, on travels in the Americas, Africa, Europe and Asia. Butterflies of Mount Diablo Webinar Recording Join MDIA naturalist Michael Marchiano to view a cross-section of butterflies found on Mount Diablo winter through fall. View the photographs of outstanding nature photographer and naturalist Dan Fitzgerald and be surprised by the number of species that can be seen on the mountain, for those that take the time to stop and look. Learn interesting facts about butterflies from the "giant" Tiger Swallowtail to the "tiny" Pygmy Blue. Find out about our MDIA Butterfly Guide and (in the future when COVID restrictions permit) join MDIA leaders on a butterfly hike. California Naturalist Graduate Projects Webinar Recording This is a symposium showcasing Cal Nat graduates as they share their capstone projects. Dan Sandri, Harry York, Linda Kwong, and Tere Dixon completed some amazing projects for their class. Their projects cover a wide range of naturalist topics including the new wildflower guide, biking highlights up the mountain, a native bee guide, and a template for outdoor science education. Watch and enjoy the creativity and passion each person brought to their project. For more information about the California Naturalist Course for the Mount Diablo Region go to: https://calnat.ucanr.edu/Take_a_class/Las_Positas_College/ California’s Iconic Oaks and Their Many Relations Webinar Recording Oaks support more life forms than any other tree in North America, and California’s oaks are no exception. In a presentation filled with woodpeckers, woodrats, wood ducks, and many other organisms, author and naturalist Kate Marianchild will explain why oaks play such an important role in oak woodland food webs. She will talk about animals that rely on oaks for food, shelter, foraging substrate, and more, and oak mistletoe as a keystone genus. We’ll hear about the eleven functions of a gray squirrel’s tail, and we’ll marvel at the tiny wasps who bend oaks to their bidding. We will crawl with Kate through woodrat mansions, fight for breeding opportunities with acorn woodpeckers, and navigate through an oak with the third eye of the western fence lizard. Who could stay away? Cattle's Role in Conservation Webinar Recording Cattle's Role in Conservation: You will hear from Cari Koopman, Tim's daughter, about the role grazing plays in conservation. She will share the commitment ranchers have to being stewards of the land. This two part series will give you a good understanding of current ranching practices and help you to interpret the role cattle play within Mount Diablo State Park, on both private land and State Park land. Citizen Coyotes of San Francisco Webinar Recording In this comprehensive introduction to coyotes, Janet Kessler discusses the behavior & personality of coyotes. She will be unveiling, from first-hand experience and observation, just how savvy, social, sentient and singular coyotes really are! Though Ms. Kessler is, by definition, a hobbyist, she has amassed a significant body of information in the last 17 years she has studied these coyotes. She has exhibited photographs several times in San Francisco’s Randall Museum gallery. Common Spiders of Mount Diablo Webinar Recording Step inside the world of spiders with Dr. Jack Fraser through his pictures and stories in this webinar from Mount Diablo Interpretive Association. You'll be amazed by the widely varied locations, eating habits, and defense mechanisms of these fascinating creatures, giving you a new appreciation for spiders and how to find them—not always where you expected! Coyote Behavior in the Urban Interface Webinar recording With local human/coyote interactions fresh in the news of late, this is a timely discussion. We will address urban coyote behavior and management and the delicate interface between humans and the most persecuted keystone species in North America. How education and understanding is the only way forward. Dinosaurs of Diablo (sort of) Webinar Recording Ancient mastodons, horses, camels, saber tooth tigers, bone crushing dogs on Mount Diablo….who knew? Lisa White, the Director of Education and Outreach at the UC Museum of Paleontology will share the amazing discoveries that have been uncovered in the Blackhawk Ranch Quarry on Mount Diablo. You will learn about the paleontological digs on this site and the amazing array of plants and animals that have been found on this unique locality since research began in the 1950’s. Discover Mary Bowerman Trail Webinar Recording Join MDIA board member and California Naturalist graduate Dan Fitzgerald as he takes you on a virtual tour around the Mary Bowerman Trail at the summit of Mount Diablo. There are over 125 wildflowers that bloom on the Mary Bowerman Trail! Dan will show you some of the ones he has photographed along the trail and the butterflies he has found using them. Fire on Mount Diablo Webinar Recording Join us for a fascinating discussion about controlled burns on Mount Diablo. You will hear about the history of controlled burns, the objective, how they manage them, what are the plans for the future, and how sites are selected. This is a timely topic as there is much discussion locally and nationally about this strategy for resource management. Presented by Mason Hyland, Senior Environmental Scientist and Christina Lew, Environmental Scientist at Mount Diablo State Park. Forest Bathing Webinar Recording Ever notice how a walk in the woods seems to magically clear your mind or spark new ideas? Come learn all about what’s behind that feel-good forest effect! Join certified forest bathing guide Anya Starovoytov as she introduces us to the calming, science-backed wellness practice of forest bathing—a mindful, sensory-based experience inspired by the Japanese practice of Shinrin Yoku. It’s not about exercise or getting your steps in—it’s about slowing down, tuning in, and letting nature work its magic on your mind and body. You’ll learn how forest bathing can reduce stress, ease anxiety, boost your immune system, and even improve heart health. Plus, Anya will share her journey to becoming a guide and lead a short, remote mini-session so you can get a taste of the practice—no forest (or swimsuit) required. Step into the calm. Slow down. And discover how nature can help you hit the reset button. Forgotten Landscapes of California Webinar Recording Laura Cunningham, an accomplished artist and author, presents this webinar. Cunningham’s life's work is at once a celebration of California’s past – its natural legacy of abundance and diversity – and of change. In A State of Change: Forgotten Landscapes of California Cunningham imagines what a prehistoric California must have looked like using research from history, prehistory, field work, and scientific illustration. Geology of Mount Diablo Webinar Recording John Karachewski, a geologist, hiker, bike rider and photographer will take you on a ride up Northgate and Summit Roads to see over 200 million years of geological history. Your front-seat journey takes you from ancient lava flows erupted on the seafloor thousands of miles away to modern landslides as you learn how Mount Diablo became the prominent natural landmark of Northern California. Geology of Mount Diablo: 2 New Publications Webinar Recording Highlights from Two New Publications on the Geology of Mount Diablo is presented by Greg Bartow. Greg discusses some brand new resources to help you understand the geology of the mountain. The first is an expansive book titled Regional Geology of Mount Diablo, California: Its Tectonic Evolution on the North America Plate Boundary. A second publication is Geologic Guide to Mount Diablo , a simplified guide in the form of a geologic trail map on one side and interpretive information suitable for the layperson on the back. Greg is Water Infrastructure Advisor, California State Parks and the editor of our new full color geologic map. Gray Foxes and Extinctions, Local & Global Webinar Recording In studying gray foxes for more almost two decades on the Bay near Palo Alto, Bill Leikam, known as "the fox guy," has good reason for his gentle but implacable statements about relentless urban development and the fast-paced loss of species across the globe. Foxes need wild lands, and so do humans. We know that, but not all humans see it that way. When Bill talks about fragmentation of habitat, we need only to think of all the hacked trails on and around the mountain to see exactly what he means. Where can the wildlife go to get away from us? Hidden Gems of Mount Diablo Webinar Recording Ever wondered why the top of Mount Diablo is inside a building? Have you seen the goldfish on one of our steepest trails? Ever visited the rock dam in Perkins Canyon? Steve Smith, President of the Mount Diablo Interpretive Association, will present The Hidden Gems of Mount Diablo, directing you to the stories and locations of some of the treasures on the mountain that might be a little less known but no less fascinating. Hiking Apps Introduction Webinar Recording Hiking applications for cell phones promise to navigate while hiking, suggest trails to get to a specific location, post reviews by prior hikers, and/or record a hiker’s actual route. These programs, when properly used, can be helpful navigation aids, but they also have limitations. The webinar includes live displays of the features of each of these applications and present hints when using hiking apps in the Mount Diablo State Park. How to Identify Wildflowers Webinar Recording What is that flower? So many of us are asked that question by visitors or for our own knowledge. Join us in this webinar to learn basic features of leaves and flowers to more easily identify wildflowers, with an emphasis on the plants of Mount Diablo. With some knowledge of visible plant structures, field guides and dichotomous keys can become friend, not frustration! Michele Stanton is a relative newcomer to the Bay Area, but she holds a BS and MS in Horticulture, and taught Horticulture in the Midwest at both the university level and for adult education. She is often a docent at Mitchell Canyon Visitor Center. Insects of Mount Diablo: Spring and Summer Webinar Recording This webinar covers some of the amazing lifecycles of the insects you can look out for on and around Mount Diablo. As we enter the beautiful season of Spring we look forward to seeing a burst of wildflowers and plant life, as well as witnessing the return of migrating birds and re-emerging reptiles. Much of the Spring activity we see on the mountain is based on the boom in numbers of insects. What are the colorful, fascinating insects we might encounter as we walk the trails of Mount Diablo in Spring and early Summer, and how do they interact with each other? Keep 'Em Flying: Helping Raptors Survive in the Human Environment Webinar Recording The presentation discusses what raptors are, how they get in trouble, and how we help them. This overview of 10 years of rescue work focuses on familiar local raptor residents, and also describes encounters with less common species and situations. We hope you’ll enjoy this insider’s look at an unusual niche of wildlife conservation. Craig Nikitas, a retired urban planner, has been a wildlife volunteer working with raptors for over fifty years. In 2015 Craig founded Bay Raptor Rescue to provide a free service to aid predatory birds in distress. The work is done under permit from the US Fish and Wildlife Service, and the Cal Department of Fish and Wildlife. His work comprises trapping free-flighted birds (most often in buildings), netting birds grounded by illness or injury, and transporting those which need veterinary care to local rehabilitation facilities. Lizards of the Diablo Range Webinar Recording Did you know there are over a dozen species of lizards inhabiting the Diablo Range? Join Joseph Belli as we take a closer look at these diverse reptiles! Joseph has studied lizards in the Diablo Range for years and has amassed a deep understanding of the lizards through observation and scientific research. You will be amazed at the diversity of this species which goes far beyond the usual lizards we see on the trail! Joseph Belli has hiked and explored the Diablo Range extensively since the 1970s. He holds a Master of Science in Conservation Biology and has worked as a wildlife biologist for the National Park Service. Migration Cut Short: Local Trout and Salmon with Nowhere to Go Webinar Recording For millennia, the first rains of autumn have signaled the start of the annual run of Chinook salmon, also known as king salmon, in the Walnut Creek watershed. Steelhead and resident rainbow trout begin later, in the fall, winter, and on into spring. But since the 1950's, flood control concerns of fast-developing cities have spelled doomsday for these native fishes. In Mitchell Creek, for instance, the last sightings were in the late 1980's. The good news: restoration of Pine Creek, for instance, on MDSP's western edge, would be "relatively easy" according to our speaker, James Hale, known as Doc, a vertebrate zoologist who has spent 50 years studying the wildlife of the East Bay. Can we recover other creeks, and what would it take? Mitchell Canyon Birding Hotspot – Spring Migration Webinar Recording Spring in the East Bay outdoors means enjoying comfortable weather, looking at beautiful wildflowers, and greeting the colorful migratory birds flying up from further south that either settle here to find mates and nest, or stop briefly before continuing up north. Mitchell Canyon, on the north slope of Mount Diablo and lying within Mount Diablo State Park, is known by birders as perhaps the best place around to see this annual rush of feathered color and song. In this presentation you will see some beautiful birds, fascinating migratory maps and learn what we all must do to help Mitchell Canyon’s beautiful birds survive. Presented by Juan Pablo Galván Martínez (Mount Diablo State Park volunteer, Mount Diablo Audubon Society Conservation Chair, and Senior Land Use Manager for Save Mount Diablo). Mount Diablo Survey Markers Webinar Recording The history of property mapping in California after it became a state in 1850 begins at the summit of Mount Diablo. The mountain’s prominence on the landscape made the summit the perfect location for early land surveyors to mark the starting point for a grid of lines that would be used to define property boundaries throughout most of northern California and all of Nevada. Surveying expert John Pettley will discuss the history and significance of the survey marks on top of Mount Diablo which are still in use by land surveyors today. Mushrooms on the Mountain Webinar Recording Let’s start the new year off by joining Michael Marchiano to discover the wide variety of mushrooms that call Contra Costa home. You will see some of the wonderful photos that Michael and Dan Fitzgerald have gathered of various mushrooms and learn about their habitat and life cycle. Are mushrooms plants or animals or something else? Discover these answers and more at this fun webinar. Michael Marchiano is a widely respected naturalist, presenter, hike leader, teacher and a passionate advocate of Mount Diablo. Native Bee Guide to Mount Diablo Webinar Recording Join us for this webinar to celebrate the release of a new pocket guide, Native Bees of Mount Diablo. Author Dan Sandri, who is an avid naturalist and entomologist, has created this new carry-with-you book. Dan will share with you the development of the guide as he presents an interesting and lively webinar about the many species that make Mount Diablo their home. Native Bees of Mount Diablo Webinar Recording It is Springtime and native bees can be seen all over Mount Diablo: on the wildflowers, blooming shrubs and trees, and patrolling the trails of the mountain. Join entomology enthusiast and MDIA Board member Dan Sandri for a presentation about the native bees of Mount Diablo, and learn what these bees are doing. See tips on how to identify some of the most-common native bees found on the mountain, and hear about their life cycles and habits. How long do they live? What are the threats they face from predators, parasites and the changing environment, and what can you do to help them? Native Trees of Mount Diablo Webinar Recording Wildflowers are the divas of springtime, but the allure of our native trees extends through every season. Join us for a virtual stroll up Mitchell Canyon and indulge your inner druid as we share fascinating tidbits about Diablo’s dendritic darlings. How is climate change and habitat loss impacting our native trees? What tree was the original source of aspirin? Which is the “gasoline tree”? And which tree offers a goodly but inedible crop of “California pears”? We'll also share tales of early day botanical explorers who risked life and limb to learn the secrets of the trees. Native to Right Here: the plants, animals, and people of Tuushtak Webinar Recording In this 25-minute film premiere, Cafe Ohlone founders Vincent Medina and Louis Trevino lead a walk in the hills below their most sacred peak, Tuushtak, aka Mount Diablo. As they point out plants and animals along the way, they discuss Ohlone history, culture, and cuisine—and how we can all celebrate what is "native to right here." Vincent and Louis have graciously agreed to answer your questions following the premier. Sponsored by Mount Diablo Interpretive Association. Videography by Wally De Young. Music by Phil Heywood. Photos by Scott Hein, Arnold Joe, Cindy Roessler, Wally De Young. Production by Joan Hamilton. Newt and other Amphibians of Contra Costa County Webinar Recording With Winter rains come the filling of ponds and streams and the emergence of our local frogs, salamanders, and toads returning to their seasonal mating grounds. Find out which Amphibians live in our county and their role in the environment. Learn about the endangered species that live on Mount Diablo and how they survive our long hot summers. Maybe one or two live specimens will appear on your screen. Night Sky Above Mount Diablo on the Winter Solstice Webinar Recording Please join MDIA in looking upward to the skies. We will have an amazing presentation by Steve Jacobs, president of the Mount Diablo Astronomical Society (MDAS) and colleagues talking about the programs they conduct at the summit, and about how the winter solstice (December 21) will have an effect on humans, animals, and plants as we change the seasons. Join us for this fascinating program to learn about the sky above Mount Diablo and see some of the beautiful images of the night sky their members have produced. On Track for Excellence: Animal Tracking Webinar Recording Meghan Walla-Murphy is an expert tracker who lives in Northern California. In this presentation, her focus "is a blend of writing and environmental conservation with an emphasis on wildlife corridors and linkages," a core interest for all of us around Mount Diablo. We'll learn how to be fully present on the trail, open to all detail by walking slowly to note even the faintest tracks. She'll show us how to judge the number of individuals (pigs or deer, for instance), the weight, and, potentially, the gender. That'll take some practice, and February -- if we get more rain -- is a good time to put new tracking skills to the test. See her website here: http://www.meghanwallamurphy.com . Opossums: Misunderstood Webinar Recording Opossums are a small non-native mammal. It is North America's only marsupial and has an interesting physiology, such as a pouch to hold developing young, and a gestation period of 13 days. Opossums can be seen in both urban and rural environments, and have adapted new behaviors to live in an urban environment. Didelphis virginiana is considered a 'generalist' and has a loose set of cultural requirements that adapt to different habitats. These animals are generally misunderstood and viewed as aggressive. One reason for this view is because they hiss when threatened. Aggression is not an accurate depiction of it's behavior. Opossums are a part of our world, as we are a part of theirs. There is much to learn! Peregrine Falcons of Pine Canyon Webinar Recording Join Peregrine Team leader Staci Hobbet and Wally De Young for an up close and personal look at the Peregrine Falcons of Pine Canyon. You'll learn about this incredible apex predator and the remarkable success story of their reintroduction after local extinction; the mission of the volunteers known as the Peregrine Team; as well as a look at the struggles the Peregrine encountered this very season. Ranching History Webinar Recording Ranching History: This ranch has been run by the Koopman family since 1918 and has continually evolved practices to become a model of conservation ranching. You will hear stories of this ranching history from where it started, to what it has become today. Rare Plants on Mount Diablo Webinar Recording Join our experienced naturalist Dan Fitzgerald, as he takes you on a virtual hike from Mount Diablo's lower elevation to its summit and see what are some of the rarer and less observed blooming plants on the mountain. You will be treated to some stunning photos and a lot of insight about these plants as Dan travels the mountain in search of these rarer plants. Rat Poison Kills More Than Rats Webinar Recording Is rat poison our “new DDT”? Raptors are the Solution (RATS) will discuss the impacts on wildlife being caused by anticoagulant rodenticides in the food web. RATS will explain the effects of these poisons on birds of prey as well as on bobcats, mountain lions, foxes, and Pacific fishers, among many other animals, including domestic pets. We will discuss AB 1788, which went into effect on Jan. 1, 2021, and RATS’ legal efforts to better regulate these poisons, as well as alternatives to rodenticides, and what individuals and municipalities can do to help beneficial predators thrive and continue to provide us with their free, natural, pest control services. Rattlesnake vs Ground Squirrel: The Predator Doesn’t Always Win Webinar Recording Do you root for the underdog ground squirrel or the hungry snake? Armed with potent venom, a rattlesnake is not guaranteed to come away with the prey. Join Park Interpreter Sharon Peterson to explore surprising details of the relationship between rattlesnakes and ground squirrels. Reptilian Mount Diablo Webinar Recording What reptiles inhabit our open spaces? Snakes, Lizards and even a Turtle are found on Mount Diablo. Learn to recognize these fascinating creatures on the sky-island in the middle of Contra Costa County. Join us and find out about the unusual and rare reptiles that inhabit this natural wonderland. What are the true facts about the only venomous snake found in Northern California, the Northern Pacific Rattlesnake? Find out about, "Blue Bellies, Horned Toads, and Whiptails." Join Contra Costa Native, naturalist Michael Marchiano, who has studied and photographed these amazing animals since childhood as he shares his enthusiasm for these often maligned creatures. River Otters Webinar Recording River Otter Ecology Project is a research, education, and conservation organization founded in 2012 to support healthy watersheds for otters and all the rest of us. Please join us for Supporting Conservation, Otter by Otter , a deep dive into our Otter Spotter program, what it accomplished, to whom it matters, and where we’re headed. It is a fun, educational and interactive presentation filled with photos and video of those entertaining and important predators living and thriving in the San Francisco Bay Area. We’ll also talk about the importance of the very cool Contra Costa County otters, and how they’re supporting education and conservation. Rooted In Relationship: Art and Illustration Webinar Recording Artist, writer, and illustrator Christopher Reiger presents a survey of his artwork and illustration. Christopher is fascinated with natural history, conservation, and ecology, and his visual art and writing projects wrestle particularly with the human relationship to nonhuman animal species. Christopher lives in Santa Rosa with his wife and two young sons. STILL COOKING AT 90: The Rehab of the Mount Diablo Stoves Webinar Recording Mount Diablo's rustic stone grills are viewed as part of the landscape, but they are celebrities, the enduring product of a unique effort to improve the nation's parks during the Great Depression by President Franklin Roosevelt's Civilian Conservation Corps, 1933-1942. On Mount Diablo, guided by expert stonemasons, the CCC used native stone to construct these monumental stoves, echoing the rocky beauty of the mountain. A talented and dedicated group of park volunteers are now rebuilding them with the tender loving care they deserve. The team members will tell us about their work as detectives and masons, and the characteristics of these historic monuments that are still cooking in their eighties and ninties. Sky Island Adventures Webinar Recording What do you get when you mix 3 experienced local Naturalists with Southeast Arizona and Southwest New Mexico in the height of monsoon season? Seriously Soggy Science Guys? Actually, yes… and much more: over 50 species of butterflies, 70+ species of birds, 100+ plants, 6 different toads, rattlesnakes, tarantulas, strange insects, a bear and much more. Join Dan Fitzgerald and Dan Sandri as they share their favorite photos from their adventures on the flooded roads with Michael Marchiano in 4 different mountain ranges and the lowlands that surround them. Spiders in Your Neighborhood Webinar Recording Spiders! Scary? Maybe. Cool? Definitely. Author Pat Stadille used to be terribly afraid of these eight-legged daddies, until he started learning more about them. Now spiders are his best friends. Once you hear about their silky skills, hunting habits, and generally shy and gentle nature, you might feel the same way. Learn about jumpers, wolf spiders, tarantulas, the “bird turd spider,” and, of course, the black widow. This much-expanded edition is bursting with new species and new spider science. Spiders in Your Neighborhood features detailed drawings and photos of the critters you’ll find, and sections on types of webs, how and where to discover spiders, spider anatomy, and common relatives. This edition also features guided science experiments for budding naturalists; and nature journalists will love Pat’s observation tips and drawing lessons. Grab a flashlight, your sleuthing kit, and join Pat “Spiderman” Stadille on a journey around your backyard that will leave you spinning with excitement. Tarantula Hawk Wasp Webinar Recording Lia Keener, Bay Nature’s events coordinator and contributor, will share a presentation about tarantula hawk wasps, their unique ecology, and their parasitism of tarantulas. This talk will provide an overview of the life cycle of these wasps, which are known to duel with tarantulas in the Bay Area and beyond. You’ve likely heard their characteristic weed-whacker-like buzz, on warm days during Bay Area summers, so tune in to learn more about these colorful and charismatic wasps. Tarantula Time on the Mountain Webinar Recording Michael Marchiano shares his deep knowledge of the tarantulas, why we mostly see them during these few months, which ones we see and what life is like for these gentle giants of the spider world. Don't miss this opportunity to learn more about these fascinating spiders. The Fascinating World of Bats on Mount Diablo Webinar Recording Join Corky Quirk from NorCal Bats to learn more about the amazing flying mammals of your neighborhood. Topics include flight, echolocation, their importance to agriculture and other fascinating information. As a highlight of the program, you will view three species of bats native to the Mount Diablo area. Presented by Corky Quirk, founder of NorCal Bats, who has been working extensively with bats for almost 20 years. The Joy of Foraging Webinar Recording Join Colleen Crane, local forager, on a treasure hunt for hidden edible gems in plain sight, culinary creations and discoveries about history, nature and sustainability as she talks about her experiences foraging edible plants in the East Bay. She will share how to get started foraging, resources for identifying what is edible, tips on where to legally forage and how to process foraged plants into delicious delights. The Mystery of Masting in California Oaks Webinar Recording Masting—highly variable, synchronized seed production within a population of plants—is well known among oaks. How and why oaks mast, however, is poorly understood, despite the strong ecosystem effects that acorn crops have on populations of animals, both here in California and elsewhere. In this talk Walt Koenig, Visiting Senior Scientist at Cornell University, will discuss our attempts, by means of the statewide California Acorn Survey, to quantify patterns of acorn production by California oaks with the goals of understanding how trees synchronize their reproductive efforts and the interactions between acorn production and other life-history traits, both of the trees and the animals that depend on them. Tick Talk Webinar Recording One Bite Can Change Your Life Lyme disease is prevalent in Northern California, yet most practicing physicians don’t recognize the signs and symptoms of the disease. You have to be your own best warrior. Learn how to prevent tick bites, recognize the ticks that are prevalent in Contra Costa County and the disease they carry, and what to do if you are bitten. Carolyn Degnan, COO of LymeDisease.org will talk about the steps you need to know to protect yourself, your family and your pets from this debilitating disease. Carolyn is a longtime resident of CCC and has two daughters who were bitten in the San Ramon Valley. Both daughters contracted Lyme disease and multiple co-infections while hiking and trail riding. She has been a Lyme advocate since 2002 giving Lyme prevention talks to The US Forest Service, EBMUD, PG&E, Boy and Girls Scout troops, Fire Fighters, local service clubs, etc. Any question you would like to have answered during the hour can be directed to Carolyn at cdegnan@lymedisease.org . Understanding Tarantulas (The gentle giants of Mount Diablo) Webinar Recording Join us in this webinar presented by Chris Hamilton, Assistant Professor of Entomology, Plant Pathology and Nematology at the University of Idaho. He has studied tarantulas, including those on Mount Diablo. He will talk about Aphonopelma in general, the current state of our knowledge, and what his lab is working on right now including the Aphonopelma iodius species complex – which includes the Mount Diablo spider. Virtual Hike on Knobcone Point Webinar Recording Join the two Dans as they explore the sites, flora and fauna to see as one hikes along Knobcone Point Road in the southern part of Mount Diablo State Park, and into Save Mount Diablo's upper Curry Canyon Ranch. On Mount Diablo, Spring comes early to the chaparral along the trail. The first bees begin to emerge for their Spring in the first week of January, and different species find ready nectar for energy, and pollen for their young, in the blooms of four species of manzanita along the trail. Other plants found here include stonecrops and Knobcone Pine, and they are found in just a few other places in the park. This trail is great for birding in the early season too, with opportunities to see Varied Thrush, falcons, wrentits, nuthatches and other birds. Take a virtual hike with us and learn what wonders await you for your own exploration! Watersheds in Mount Diablo Webinar Recording Mount Diablo’s and Surrounding Watersheds in Today’s World: What’s happening with the health of Contra Costa Watersheds in today’s world of political and environmental issues? Can we find any bits of encouragement amidst climate change, wildfires and political strife? Let’s take a look at the news and see if we can glean something positive from the realities of your local watershed today. Watersheds of Mount Diablo Webinar Recording Mount Diablo is an integral part of three major watersheds in Contra Costa County. This presentation will explore what a watershed is, how watersheds work and their environmental challenges. We will look at watershed management considerations at Mount Diablo State Park. Presenter for this webinar is Steve Elliott, one of the long time volunteer leads at the Park. Western Pond Turtles & Their Survival Skills Webinar Recording You may have noticed turtles in the streams and ponds of the Diablo Range and wondered how they persist in such a dry environment. This presentation will shed light on the ecology of Western Pond turtles in the Diablo Range by exploring how they use various habitats throughout the year to survive in a semi-arid land. Joseph Belli is a writer, hiker, environmentalist with a Masters of Science in Conservation Biology. Why We Need to Be Wild Webinar Recording Jessica Carew Kraft, the author of Why We Need to Be Wild: One Woman’s Quest for Ancient Human Answers to 21st-Century Questions (Sourcebooks, 2023) will talk about her journey from working in Silicon Valley tech to embracing nature immersion and learning the ancestral skills common to all humans over our 300,000-year history on earth as Homo sapiens. Jessica will call upon her training in anthropology to show why hunting and gathering is the innate and pre-programmed lifestyle for humans, why it's naturally enjoyable, and why you might want to practice wild skills to deepen your connection to nature and understand your human heritage. Wild Boar Ecology Webinar Recording Doc Hale discusses the ecology of the Wild Boar (Sus scrofa) and feral pigs in Contra Costa County. He highlights their introduction into the state, their dispersal, ecological impacts, and management. Doc has been fascinated with Wild Boar since childhood, and has researched their presence throughout history, California, and the world. Wild Cats of Mount Diablo Webinar Recording Learn about the Felidae Conservation Funds' current work with mountain lions and bobcats around Mount Diablo and throughout the Bay Area, including mountain lion ecology, history, and the challenges of sharing habitat with wild felids in California. Learn essential tips for living and recreating without fear. Our presenter will also discuss the important role of wild cats in creating healthy ecosystems and enjoy engaging photos and videos. Wild Mount Diablo Webinar Recording Get out the popcorn for a lively evening of short nature films. All were made by MDIA's very own video team—Wild Mount Diablo . Topics this year include pines, poison oak, animal babies, peregrine falcons, and early- and late-blooming wildflowers. On hand to answer questions will be naturalist Ken Lavin and team members Wally De Young, Joan Hamilton, Staci Hobbet, and Kendall Oei. Wild Mount Diablo's Far Out Film Team Webinar Recording In 2021, MDIA sponsored a new project, Wild Mount Diablo , a series of very short films on the iconic native species of Mount Diablo State Park. Joan Hamilton , director and producer of MDIA’s well-known longer film series, Audible Mount Diablo, heads the three-person production team. Joan, Wally De Young and Kendall Oei film and produce the segments. Join them along with master Nauralist Ken Lavin as they share their beautiful nature nuggets with you, along with their personal perspectives on filming each subject: ladybugs, deer, river otters, poppies, bobcats, mistletoe, kestrels, and “Wonders of Diablo 2022 .” Your blood pressure will go down, and your happiness will spike, when you let this parade of beauties pass before your eyes. Wildflowers of Mount Diablo Webinar Recording Mount Diablo Interpretive Association President and Mount Diablo State Park Docent Steve Smith discusses how some of our flowers earned their wild names, how flowers have been used by humans ritualistically throughout the ages, and why we chose some of these flowers to represent our state and country. Wildlife on the Trails Webinar Recording Share the Trails with Sue Griffin, a roving naturalist and an accomplished photographer who hikes the Diablo range daily. She will share some of her favorite wildlife photos taken in the Diablo range. You will learn some fun facts as she shares interesting stories of animal behavior. Sue will also share some photography tips she has learned along the way. Join us for this fun and interesting webinar. Yes, We'll Burn Again: A Primer On Wildfire Ecology Webinar Recording Though it's difficult to shift your mind from our Noah's Ark winter to the depths of summer, you know more fires are coming. Fire ecologist George Wuerthner will help ready us for the inevitable. He's studied fire all over the American West and will talk to us about wildfire ecology, common myths, the ecological value of fires, even high severity fires, and what we can do to protect our homes and communities. George has three dozen books to his name on environmental topics; two are about fire ecology specifically; his expertise is wide. His best-known book is Keeping the Wild: Against the Domestication of Earth. He is as well-traveled as they come. He's visited hundreds of mountain ranges around the West, 400 wilderness areas, 200 national park units, and every national forest west of the Mississippi. He lives in Bend, Oregon. iNaturalist Basics Webinar Recording In this first of a two part webinar, you will learn why iNat is such an amazing resource for scientists, researchers and nature-lovers, alike. We cover how iNat works and how to post observations. It is recommended that you create an iNaturalist account prior to the session, so you can work with it hands-on, right away. Just go to: http://www.inaturalist.org/ to sign up, and download the app in your phone's app store. iNaturalist: The Next Step Webinar Recording In this second of a two-part webinar, iNaturalist: The Next Step, you will learn how to harness the power of inaturalist.com for your own research and learning, and to share with your nature/outdoor friends. It is recommended that you create an iNaturalist account prior to the session, so you can work with it hands-on, right away. Just go to: http://www.inaturalist.org/ to sign up, and download the app in your phone's app store.

Ways to support Mount Diablo Interpretive Association Ways to Support MDIA Mount Diablo Interpretive Association is an all-volunteer organization dedicated to supporting Mount Diablo State Park. We are a 501(c)(3) organization, and our Tax ID# is 23-7444529. Donate Today! Gift Giving Make a donation to support the general operations of MDIA. Tribute gifts are also a way to remember or honor a loved one. Gifts can be one-time, or recurring. Employer Matching Gifts You can make your donation accomplish twice as much when you request a matching gift! Check to see if your employer can match your generous donation. Donate a Vehicle Donate your vehicle through Cars2ndChance and designate MDIA as the charitable organization. Cars2ndChance are vehicle / car donation programs administered by the Clayton Valley Concord Sunrise Rotary Charitable Fund and staffed by all volunteers. Become a Member MDIA counts on your support to provide docents for the visitor centers, sponsor the Junior Ranger program, guide hikes, and provide interpretive material and publications to park visitors. Support the Mount Diablo Education Center in Mitchell Canyon MDIA has officially launched a campaign to build a new Education Center at the Mitchell Canyon entrance to Mount Diablo State Park. Please join us in inspiring new protectors and champions of Mount Diablo by making a generous tax-deductible contribution today. Your gift will leave a legacy of education, protection, and wonder for the present and future generations! Gift of Stock Gifting stock is a simple and powerful way to support MDIA and the new Education Center at Mitchell Canyon. Required Mandatory Distribution If you have investments in 401k’s or similar instruments, and must take a distribution, you can direct your broker to send it to MDIA as a donation and not have to report it as income on your tax forms. Become a Volunteer Volunteering allows members to commit to as little as a couple of hours a week and still provide vital assistance to the association and park.

Privacy Policy of Mount Diablo Interpretive Association Mount Diablo Interpretive Association (MDIA) operates the https://mdia.org website (“the website”), which provides the public with information and resources on our organization’s mission and work related to the preservation and education of Mount Diablo State Park. This page is used to inform website visitors regarding our policies regarding the collection, use, and disclosure of Personal Information if anyone decides to use our Service, the Mount Diablo Interpretive Association website. If you choose to use our Service, then you agree to the collection and use of information with this policy. The Personal Information that we collect is used for providing and improving the Service. We will not use or share your information with anyone except as described in this Privacy Policy. 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Cowell Cement Industry Author: Craig Lyon (Compiled from several references - 1997) Cowell and Its Cement Industry January 1, 1997 Large Smokestack As one drives easterly on Ygnacio Valley Road across Lime Ridge northwest of Mount Diablo, scars from open pit quarry operations can be seen to the right of the road. To the left is a tall smokestack in an area that in past years was called Cowell but which is now part of Concord. This was the site of the Cowell Lime and Cement Company that produced Portland cement from 1905 to 1946. The cement plant was one of the largest employers in the area in the early 1900's. The rock was quarried in the Lime Ridge area and carried on a narrow gauge railroad, or by truck, to the Cowell plant where it was crushed, mixed with clay, and then converted to cement in roasting kilns. Sacked cement, which was marketed as "Mount Diablo Cement", left Cowell daily on the company's standard gauge Bay Point and Clayton Railroad, At Bay Point, the cars went on their way to other areas via Southern Pacific, Western Pacific, or Santa Fe railroads. Through the years farmers threatened to sue the Cowell plant over the air pollution which coated their vines and orchards with fine cement dust. The cement company built a 235-foot-high smokestack in 1934 in an effort to dissipate the dust into the atmosphere. Labor problems forced the plant to close in 1946. The plant was later torn down and the smokestack and quarries are all that remain of this once-thriving industry. The rock quarried at Lime Ridge and used to make cement is called travertine, It is the same composition as limestone - almost pure calcium carbonate. The rock is hard, sometimes shows banding, and is colored a light tan by the inclusion of a small amount of iron oxide. Cave formations are formed from the same kind of material. The travertine at Lime Ridge formed, probably in fairly recent geologic time, from circulating waters carrying calcium carbonate in solution which came to the surface through a very porous sandstone called, by geologists, the Domengine formation of Eocene age (about 50 million years old). The water evaporated, leaving behind the travertine which formed a layer on top of the sandstone that originally covered an area 2.5 miles long and 0.5 miles wide and varied in thickness up to a maximum of 20 feet. The Domengine sandstone is exposed in the light-colored quarry faces and can also be seen in the large roadcut just east of the entrance to Cal. State Hayward. BACK TO LIST

Additional Resources Browse the resources available from our community partners. 1 California State Parks- PORTS Learning materials from the State Parks https://ports.parks.ca.gov 2 California Environmental Literacy Initiative Parent Portal http:// https://partnerportal.ca-eli.org/site/contra-costa-county-office-of-education/browse/community-based-partners 3 East Bay Parks Educator resources including Ohlone 3rd Grader Program, animals and field trips https://www.ebparks.org/programs/educators 4 Lawrence Hall of Science Programs including Stem Day, Otto Initiative, workshops on matter, circuits, life science, engineering, science kits, and resources for teachers including GEM kits. https://lawrencehallofscience.org/educators/ 5 Lindsay Wildlife Museum Discovery Kits, Hikes and Programs https://lindsaywildlife.org/teachers-and-schools/ 6 Mount Diablo State Park Interpreter-Led Programs Please contact Park Interpreter Sharon Peterson via email (Sharon.Peterson@parks.ca.gov ) for information regarding School Group Programs and/or Education Tours. Presented by California State Parks. https://www.parks.ca.gov/?page_id=517 7 Save Mount Diablo About the Mangini Ranch Educational Preserve and how to reserve a field trip. https://savemountdiablo.org/what-we-do/educating-and-inspiring-people/mangini-ranch-educational-preserve/ Next Generation Science Standards (NGSS) Back to Learn Download the NGSS Fact Sheet

Swallowtail Butterfly by Jenn Roe Marvelous Animal Adaptations May 21, 2025 by Dan Fitzgerald Yes, tigers are on patrol in Mitchell Canyon from early spring till late fall. But these creatures have no claws or teeth. They are tiger swallowtail butterflies that depend on flight and colorful camouflage to keep safe from harm. Four types (species ) of swallowtails are found here, and of the four, the Western Tiger Swallowtail is the most frequent flyer. The swallowtail’s name comes from its hindwings (lower pair of wings) that are similar in shape to that of a bird, especially the swallow. Although only about four inches wide, it’s still one of North America’s largest butterflies. Why do these flying tigers have stripes? How do its stripes, colors and other features help it escape enemies, especially hungry birds? Its colors are camouflage that help this butterfly hide in plain sight. The bright yellow and black wing patterns blend with the light and shadows of a woodland habitat , where it lives in the wild. The hindwing’s blue and orange dots are eyespots that fool predators into attacking the lower wings (thinking it’s the head) instead of the butterfly’s real head and body, which would inflict more serious harm. The swallowtail’s large wings and eyespots can also fool some predators into thinking it’s a larger, more dangerous creature and should be left alone. This way the butterfly lives to fly another day. How do butterflies eat? Adult butterflies are herbivores, plant eaters same as gophers and deer, but they can’t chew. Instead of teeth, all butterflies have a long tongue, called a proboscis . A proboscis works like a straw to sip sugar-rich nectar from flowers, a butterfly’s main energy source. Western Tiger Swallowtails also sip from damp places like mud puddles to gather important minerals needed for overall health. Download this article By Dan Fitzgerald A Pale Swallowtail shows off its stripes. by Dan Fitzgerald The Anise Swallowtail is another swallowtail species found in Mitchell Canyon. Here it is using its long proboscis to sip from a flower. BACK TO LIST

An Island in Suburbia by Naturalist Michael Marchiano April 1, 1998 Mount Diablo is an island in the middle of suburbia. It is a diverse habitat of cool wooded canyons with flowing creeks and cataracts in winter, spring, and early summer. It is a wooded oak forest, a grassy savannah, and a wonderment of rocky slopes covered in fascinating chaparral growth of ceanothus, chemise, manzanita, sages, toyon, currants, and silk tassels. It is a treasure of wildflowers in springtime and summer, a paradise for bird watchers, a challenge to hikers, and until recently, a mystery to geologists. I was fortunate to be born and raised in the East Bay, living at the base of the Mountain since my early childhood. My first experience of snow as an eight-year-old was when my mother drove me, my brother, and our neighborhood friends up to Mount Diablo after one of those low elevation snow storms. I experienced cold snow and the worst case of poison oak I have ever had. Yes, you can catch poison oak in freezing weather from the leafless twigs of a poison oak plant. As a Naturalist, I fell in love with Mount Diablo years ago. The various intriguing habitats offer a richness and fantastic diversity of plant and animal life. I am constantly learning new things every time I explore an area of the mountain. I first hiked it as a child and then as a teenager. I lived on the mountain for one year in my early twenties, fulfilling a childhood fantasy of working for Diablo Ranch as a cowboy. As a young adult, I led outings for the Lindsey Museum, 4H groups, schools, and scouts. As a teacher, I had my 8th grade science class do a full semester ecology study of the mountain, including several camping and field trips. Students that I have run into years after I had them in class have told me their greatest memories of junior high were the explorations and camping trips on Mount Diablo. Many can still recount to me the specific animal or plants that they wrote about for their project. When a child or an adult mentions his or her fear of snakes or spiders and then at the end of a presentation or hike volunteers to touch or hold one of these creatures, it validates all of the effort to do these programs. By volunteering with the Mount Diablo Interpretive Association (MDIA), I have been afforded the unbelievable opportunity to share this wonderland with school groups, organizations, and visitors from near and far. In all of these endeavors I have had the opportunity to impart some of my love for the mountain to others. I have been given the chance to show people the wonders and mysteries of the marvelous plant and animal life on Mount Diablo and in the surrounding foothills. Seeing the amazement and wonder in people’s eyes as they learn about the relationship between a local and harmless tarantula and its foe, the tarantula "Hawk", or see a coyote in the wild for the first time, or watch a peregrine falcon flying overhead, is a great reward for me. Saving and protecting Mount Diablo for all the flora and fauna is of paramount importance, but educating the public, especially upcoming generations as to the significance of biodiversity, whether the smallest microbe or an apex predator like a mountain lion, is also crucial. MDIA has become a crucial link between the park and the public. For example, seeing the evidence of badgers on the north/west side of the Mountain for the first time in 40 years is extremely rewarding. It means that efforts to ban poisoning of ground squirrels and other rodents may be having some positive effect. Mount Diablo is home to many rare and endemic plants, as well as several protected and threatened animals. In spring, people can easily see over 75 different wildflowers, 40 different species of birds, and 15 different species of butterflies all within a two-mile walk. Add to that the beautiful oaks, maples, buckeyes, pines, and other lush shrubbery, and you may feel like you are in the Garden of Eden. Because of the enlightened thinking of prior generations and the continued effort of this generation. I am able to walk out of my home in Martinez, enter a public access path maintained by the Contra Costa Water District and East Bay Regional Parks, walk along this trail to Shell Ridge in Walnut Creek or Lime Ridge in Concord, into Foothills Park, following Pine Canyon into Mount Diablo State Park, hike over Curry Point, down the back side of the Mountain into Morgan Territory Park, into Round Valley Park through Los Vaqueros Reservoir property, and over to Brushy Peak on the Alameda County border. Many of the missing pieces of property that have made that trip possible were put in place by Save Mount Diablo. With the continued support of this and our next generations, that quilt of open and protected space will continue to grow for all generations to enjoy. BACK TO LIST

Variable Checkerspot by Dan Sandri March 24, 2025 Dan Sandri Here's a super-common butterfly - the Variable Checkerspot. Also known as the Chalcedon Checkerspot, the Variable Checkerspot is more commonly seen on Mount Diablo right now as a caterpillar. The caterpillars are black, with orange markings, which warn potential predators that they taste bitter due to the iridoid glcosides they accumulate from the plants they eat. Caterpillars can be seen now feeding on the leaves, flowers and bracts of Indian Paintbrush, Monkey Flower, Penstemon , Plectritis , California Figwort (aka California Beeplant, aka Scrophularia californica ) and many other plants. When they reach full size, they drop off into the leaf litter, or under fallen limbs or rocks, and pupate. They will emerge as adults the following Spring. There is one generation of butterflies per year. Why are they called Variable Checkerspots? The adult comes in many shades, with the top of the forewing colored with a mix of black, orange, or brown, with a mix of yellow, red, or white spots, or some combination of some or all those colors (see the difference in the 2 adults shown here). The smaller male butterflies show mostly in April – June and patrol constantly for the larger females. Soon they will be one of the most common butterflies seen on our hikes/rides. But see the caterpillars now! Catepillar form of Variable Checkerspot (Euphydryas chalcedona) Variable Checkerspot (Euphydryas chalcedona) Variable Checkerspot (Euphydryas chalcedona) BACK TO LIST

Dragonfly By Jenn Roe and Dirk Muehlner Marvelous Animal Adaptations May 21, 2025 by Dirk Muehlner The dragonfly’s large compound eyes are made up of thousands of optical units which help the dragonfly see in almost every direction at the same time. An almost 360 degree world view; now that’s super vision! Why does a dragonfly need to see everywhere at one time? How does this adaptation help the dragonfly survive in its wild habitat ? What other adaptations allow it to succeed? Flying Hunters The dragonfly is an avid carnivore of the insect world and skilled hunter often on the lookout for smaller flying insects. Its large compound eyes peer in every direction but behind, which is how it finds its prey and watches out for enemies. The dragonfly is built to fly fast, up to 30 miles per hour. With its strong, agile wings and long, narrow body, it zips through the air to snatch slower flying insects for a quick meal. Also, the dragonfly has a strong jaw for tough chewing of crunchy prey. But don’t worry – while its bite may be lethal to insects, it won’t hurt a human handler (however, please handle with care always!). Download this article by Dirk Muehlner A dragonfly’s skilled flight make it an awesome predator and helps it avoid being eaten. Its enemies include other fast flyers like some birds, bats, and sometimes other dragonflies. BACK TO LIST

Mixed Evergreen Forest Excerpted from MDIA's book Plants of the East Bay Parks, by Glenn Keator, Ph. D. Plant Communities of Mount Diablo State Park January 1, 1999 Madrone, Arbutus menziesii Where oak canopies overlap, conditions favor a variety of other usually evergreen trees: California bay laurel, madrone, Douglas fir, tanbark oak (not a true oak but a lithocarpus), and California nutmeg. The Douglas fir and California nutmeg are not met with in our own region, while the other trees are. These mixed forests represent habitats intermediate in winter rainfall and summer drought between redwood forests, where summer fogs and heavy winter rains rule, and oak woodlands , where we've already seen the the severity of summer drought. Often there will be no absolute line and mixed-evergreen forest nudges the borders. Generally mixed-evergreen forests occur on north-facing slopes where south slopes are home to oak woodland. However, mixed evergreen forests may carpet a canyon bottom alongside the narrow riparian corridor but give way to oak woodland or chaparral on adjacent slopes. Often, too, the mixture of trees in these forests varies from locale to locale. Close to the coast, expect to see Douglas fir (Pseudotsunga menziesii ) and California nutmeg (Torreya californica ) in the forest; inland, expect to encounter canyon live oak. California black oak, California bay laurel, and madrone. The complex interactions of different trees from site to site are still not fully understood, for they also change with the age of the forest and its fire history. With the exception of a few deciduous trees -- California black and Garry oaks, California buckeye, and occasionally bigleaf maple -- mixed evergreen forests have the leathery, tough evergreen leaves so characteristic of chaparral shrubs. Unlike those, however, mixed-evergreen forest tree leaves tend to be broader and -- at least on lower branches -- horizontally oriented, for purposes of more efficient light absorption for photosynthesis. Only near the tree tops and only in some species (such as madrones) are leaves obliquely inclined, with pale undersides held skyward to reflect away intense summer sun. Although in mixed-evergreen forests as elsewhere wind pollination is used for the conifers and oaks, both madrone and bay laurel differ sharply, having insect-pollination strategies. Madrone produces abundant, nectar-rich white bells in mid-spring (bee favorites); bay laurel makes long lasting sets of small, pale yellow, saucer shaped flowers from mid-winter to early spring. Bay laurel is thus especially important in sustaining insects active at at time of year when most life is dormant. It joins ranks with the manzanitas in fulfilling this important role. As to seed dispersal, strategies resemble those of oak woodlands; again with many nutrient rich stored foods in extra large seeds. Only the madrone makes bright red-orange berries, attractive to large numbers of birds. Where Douglas fir occurs, its seeds are winged and wind distributed. This makes good sense, for Douglas fir is taller than the other trees, and winds easily reach its tall branches laden with seed cones. Not only do the roots of these trees extend outward for great distances to pick up as much of the winter rains as possible, but the competing understory plants -- shrubs, bunch grasses, bulbs, and perennial herbs -- seek water for later use. This intense competition for water means that the drier areas with least winter rainfall, where mixed-evergreen forest is marginal at best, have poorly developed understory vegetation. At the opposite pole, along the edge of redwood forests, the understory may be rich and varied. Most smaller plants are perennial; the annual life cycle is not favored by the relatively low light intensities. Many of these smaller plants extend into adjacent communities. The moisture-loving kinds extend into redwood forests and the droughty kinds -- especially the few bunchgrasses, such as melicas and California fescue --into oak woodlands. California bay laurel | Glenn-Keator Bay Laurel Trees near Juniper Campground | Dereck Love BACK TO LIST