This is the last of my four posts about Santa Rosa Island. It is simply a photographic tour of plants that have not yet been highlighted in previous posts including other interesting, rare, endemic, and common Santa Rosa Island plants.
- Santa Rosa Island Plant list I generated from CalFlora
Epic floral displays along the beaches.
Santa Rosa Island Torrey pine (Pinus torreyana ssp. insularis)
The first time Santa Rosa Island landed on my plant exploring radar screen was when I learned about the Torrey pine some time in the early 2000s. I had never even seen this tree until I took a trip to Torrey Pines State Reserve north of San Diego in early 2012. It is the rarest pine in North America with several thousand “mature” trees on both the mainland and island. My bucket list for understanding the ecology of this species is complete now that I have visited the island.
As mentioned in an early post, pigs were first introduced on Santa Rosa in the mid 1800s. By 1888 it is estimated, based on historical records, that there were only 100 Torrey pines on the island. Today, all herbivorous megafauna have been removed (minus 5 sterile horses from the old ranch) and the Torrey pine are thriving–with an estimated 12,300 trees–one-quarter of which are saplings!
Researchers debate the arrival time of the Santa Rosa Torrey pine, estimating anywhere from 6,000 to over 1 million years. Disagreement also exists as to whether these two population represent subspecies or varieties of each other. Some argue the two populations are genetically different enough to be considered a subspecies, others prefer distinction at the variety level. Regardless, it is a beautiful species and well worth seeing in the wild.
The cloud forest on Santa Rosa Island.
Santa Rosa Island
We passed five Orcas (Orcinus orca) on the passage to Santa Rosa Island
After a two hour boat ride from Ventura Harbor that included sightings of gray and killer whales, passengers disembarked onto a newly-built pier and subjacent white sand beaches. We had arrived. Once unloaded, the park ranger offered an orientation rejoicing in our good fortunes. The high winds and thick fog which had typified the previous few weeks had now subsided. The forecast for the coming days included sun, low winds, and perfect temperatures.
Fog and wind are omnipresent on Santa Rosa Island and play a major role in shaping the landscape. Any plants with a propensity for upward growth are restricted to canyons, particularly north sloping ones. Here they find refuge from the wind and often more available moisture provided by the meager 15-20 inches of annual rain. However near the highest island peaks–like Black Mountain at 1,300 feet plants have adapted to wind and fog in different ways.
Channel Islands National Park
Santa Rosa Island overview.
In 1998 I first visited the Channel Islands. This was early in my naturalist career but I was struck, none-the-less, by the beauty and isolation I found on Santa Cruz Island. On that trip I first saw the endemic island scrub jay (Aphelocoma insularis) and began to develop an understanding and interest in island biogeography. Twenty years later this experience brought me to Santa Rosa Island–in major part to see the Torrey pine grove–but also for the opportunity to explore one of the least visited places in Southern California.
Santa Rosa Island is separated from the mainland by over 25 miles of water. The next closest landmass is San Miguel, which is now isolated from Santa Rosa by three miles of water. Isolation has nurtured endemism on both a localized island level as well as on a unifying level between islands. Combined, all the Channel Islands are home to 150 species of unique plants and animals. Santa Rosa hosts 46 of those, including six endemic plants that grow nowhere else.
The National Science Teachers Association conference brought me to Los Angeles and after two days, I needed to find some green space. Linking up MacArthur Park, Vista Hermosa Natural Park, and Whole Foods (to prep for a trip to Santa Rosa Island) defined a route for me to visit the urban wildlands of the city.
Stroll to the sparse urban wildlands near downtown Los Angeles .
My elegant crossing Tule Creek. Photo by Josh Smith.
Last weekend, I hiked in Trinity County along a low-elevation, fire-prone section of the Bigfoot Trail between Highway 3 and Hayfork and was able to witness obligate & facultative seeding in action.
From Field Guide to Manzanitas, Backcountry Press, 2012
One-third of manzanita species are facultative seeders. These are species that regenerate post-fire by both seed and burl resprouting. The remainder are obligate seeders that lose their entire adult population in a fire and depend on a seed bank for regeneration. Obligate seeding is the current model in manzanita evolution.
To understand why, consider the climatic dynamics over thousands, or tens of thousands of years or more. In the case of the resprouting species, particular individuals can live for centuries, resprouting over and over, cloning new individuals as the burls expand with each fire cycle. But in that population, the rate of genetic change is limited, because most individuals live a long time by way of asexual reproduction. This suggests that populations may be unable to respond to rapid climatic changes that might occur in only hundreds of years. The obligate seeders, on the other hand, lose all adults in stand-replacing fires and new post-fire generations have to establish from more genetically diverse seeds. Those populations consequently have greater flexibility to shift and adjust as circumstances require; traits that might have been rare and less important in older generations can emerge through natural selection and become critical in the newer generations within the lifetime of resprouting manzanitas.
Much of this area burned in the summer of 2015. While evidence of the fires were everywhere, there are many signs of the next generation of plants returning to the landscape. This was particularly true on some of the south-facing slopes above Philpot Campground where two species of manzanitas were exploring different reproductive regimes– both obligate & facultative seeding.
Arctostaphylos manzanita is a facultatative seeder. It can resprout by seed but also from dormant buds. When present, these structures are often prominent and are called burls (also ligno tubers)–seen in the middle of the sprouting leaves.
Arctostaphylos canescens is an obligate seeder and does not have a burl. Instead, genetically unique seedlings resprout from a well-stocked seed bank.
A large burned stand of the obligate-seeding hoary manzanita, above Philpot Campground on the Shasta-Trinity National Forest.
Hot springs and tall trees, all hidden in a remote area of Mendocino County. This was the family destination for a pre-Thanksgiving celebration. Most or our time was spent at Orr Hotsprings but an day-hiking excursion treated us with a fabulous adventure in an isolated redwood grove at Montgomery Woods State Natural Reserve.
The hike was punctuated with firsts: my son’s first multi-mile hike and my my first albino redwood. The park previously held the tallest recorded redwood — at 367.5-foot it was once declared the world’s tallest. While the Montgomery tree is still alive, the new record is in Humboldt County. Other exciting finds in the park included an excellent expanse of giant chain ferns in a lowland basin along the trail. Read more about Montgomery Woods from Save the Redwoods League.
Arctostaphylos nummularia subsp. mendocinoensis
The pygmy manzanita (Arctostaphylos nummularia) is a species endemic to Mendocino County, California where it is known from its occurrence in the pygmy forests along the coastline. I think this might just be the perfect northern coastal California shrub for a native plant garden. It has a perfectly rounded form, beautiful small leaves, and subtly hairy stems.
Arctostaphylos nummularia subsp. mendocinoensis by Allison Poklemba
Select Forest Pathogens of California’s Klamath Mountains
Forest Pathogens often go unnoticed while exploring, but offer an exceptional window into the intricacies of forest ecology when better understood. I created the free document linked below in 2011 while in Grad School at Humboldt State. Forest Pathology was one of the more interesting classes I took while turning Conifer Country into my thesis for a Master’s Degree in Biology. Most of the information for this document was taken from Terry Henkel’s lecture notes as well as from internet and book sources–all cited within the document. I was recently reminded of this creation because of the October weather that has dropped unprecedented amounts of rain and nurtured fungal growth across Northwest California.
Free PDF Download
Citizen Science in the Siskiyous
I recently started a citizen science project with 5 classes of high school biology students from Fortuna, California. The plan is to combine their observation skills with the technology offered by iNaturalist. Each month they will visit Rohner Park and record data on a chosen spot in the forest–looking for plants and animals as well as changes in canopy and ground cover. As they become more proficient in species ID, students will also upload observations to our iNatural Project ultimately creating a field guide to their local forest. We all know how much I like field guides…
My plan, over future visits to wilderness areas, is to start similar citizen science projects. The first attempt at this wide-ranging project began this week on a visit to the Bear Peak Botanical Area on the Klamath National Forest. I originally wrote about this area in my book Conifer Country because it is unique in many ways, including the populations of yellow-cedar found here. This species in common further north, but quite rare in California.