Exploring the San Gabriel Mountains National Monument
In my search to understand Bigcone Douglas-fir (Pseudotsuga macrocarpa) within the Angeles National Forest, I found myself in secret canyons and along steep hillsides that few people have ever explored. I thus took it upon myself to document more than just our selected data plots for Bigcone. In previous posts, I’ve shared some of the large angiosperms I’ve run across. Here is the documentation of the second largest Pseudotsuga macrocarpa yet measured — a record Bigcone Douglas-fir.
This Bigcone was found on the edge of a wash called Holcomb Canyon within the Devil’s Punchbowl Natural Area. The tree is nearly as big around as the record specimen in Baldy Village but just not as tall. I have heard a rumor that the Baldy tree lost some of its crown — so I wonder if the numbers I have for this tree are still correct. Regardless, the tree in the Punchbowl is much more dramatic, being that it is within the Pleasant View Ridge Wilderness and not in the middle of town!
Record white alder within the Pleasant View Ridge Wilderness.
I need to start by clarifying something: in last post about a giant Canyon Oak, I mentioned that I was not a big tree hunter. This post, a few days later, is about a big tree. I think I have become a big tree hunter…
Every day for the better part of the last two weeks, I have been walking through the San Gabriel Mountains getting to know Bigcone Douglas-fir as part of a project with the Angeles National Forest and the California Native Plant Society. I’ll post more about that in the near future. For now, lets look at the white alder (Alnus rhombifolia) I measured in the Pleasant View Ridge Wilderness within the San Gabriel Mountain National Monument while working on that project. Stats on the past record tree can be found HERE.
Crown spread: 46′
The Transverse Ranges hold some of the largest oaks in North America
I fell in love with this Canyon Live Oak (Quercus chrysolepis) in 2002 while training to prepare myself to hike the Continental Divide Trail. One fateful night I inadvertently camped near it along a stream called Prairie Gulch. The tree has lived in my dreams ever since. In November 2015, the opportunity to return, revisit and measure the oak was offered while doing a botany project in the San Gabriel Mountains National Monument.
The San Gabriel Oak
A subduction event.
One of the most interesting geologic stories in western North America is told by the ultramafic rocks that were formed deep in the ocean floor. As the Pacific Plate collided and dove beneath (subduction) the North American Plate, the bottom layers from deep oceanic mantle were scraped (obduction) onto the North American Plate. These depositions are referred to as ophiolites and the Klamath Mountains present some of the most extensive examples on Earth.
Serpentines of the High Divide with Jeffrey Pine and Knight’s Pinemat Manzanita in the foreground– by John O. Sawyer.
The 346,177 acre San Gabriel Mountains National Monument was dedicated in October 2014 by a proclamation by President Obama after nearly 10 years of work to get it established. It contains the Sheep Mountain Wilderness, the San Gabriel Wilderness, and Pleasant View Ridge Wilderness as well as most of the major peaks including Mount San Antonio, Mount Baden-Powell, and Throop Peak.
I’ve been contracted by the US Forest Service, in partnership with the California Native Plant Society, to map Bigcone Douglas-fir in the monument as well as write a technical report about our findings. We did initial reconnaissance last week and will return later this year to initiate the project’s data collection phase. What follows are images from our trip across the range to meet the species and the monument.
Looking deep into the San Gabriel Wilderness.
Because I will undoubtedly be making more posts about PSMA, as I embark further into a mapping and monitoring project in the San Gabriel Mountain National Monument, I thought a post that provides an overview of this amazing species would be in order.
Bigcone Douglas-fir in the San Gabriel Mountains.
It has been called the desert fir (Jepson 1920), bigcone spruce (Munz 1959), false hemlock (Sargent 1884), and ultimately bigcone Douglas-fir (Abrams 1923). Clearly there was confusion as to this species relationship to other members of Pinaceae. It is now described as a Pseudotsuga, being ecologically distinct from its taxonomically complex western North American counterpart, Douglas-fir (Pseudotsuga menziesii). In addition to bigcone in Southern California, five other species of Pseudotsuga occur across Canada, USA, Mexico, Japan and China.
I have always wanted to visit the San Dimas Experimental Forest and as part of a mapping and monitoring project for bigcone Douglas-fir, I finally had the opportunity. The “forest” descriptor in the area’s title is a bit misleading, as the majority of the vegetation is chaparral–but there are trees and it was our mission to find them (or at least what remains). Six major fires have been documented here since 1914, with the most recent occurring about 10 years ago. These fire events, along with climate change, are rapidly reshaping the remaining stands of trees. What follows is a photographic journey into the front range foothills of the eastern San Gabriel Mountains.
Cucamonga Wilderness from the San Dimas Experimental Forest.
This was one of the most relaxing vacations I’ve had since we visited Hawai’i several years ago. There was no work to be done, no agenda to maintain–just time to swim, rest, and of course botanize and bird the Maine woods (click HERE for my bird list). I had one target plant to find in Maine–Kinnikinnick. I wanted to see a manzanita on the East Coast. This might have been the most difficult part of the vacation, being as it took me nearly 10 days to find the species! But on the second-to-last day, in Acadia National Park on the summit of Cadillac Mountain, we found it under a layer of fog. What follows are some images from the trip. Happy Plant Exploring.
Kinnikinnick (Arctostaphylos uva-ursi) in Maine.
The action of changing the arrangement, especially the linear order, of a set of items (what came first, the conifer or the cone?)
Wandering Devil’s Hole Ridge, miles from anything human, the landscape shifts as quickly as the juncos dancing across the trail. Walkabouts bring a level of focus not found in civilization. Walking offers time to hypothesize about the world at a slower pace…How recently did the vegetation patterns I see come to be? When did the Ash-throated flycatcher arrive from its tropical winter-land? How did I find myself in this desolate, isolated place–seven years after I last visited–and so far from my family? Like the undulating contours on the ridgeline, I ponder my place in this dynamic world. Walking further I realize, while out of place, I am fortunate to be here with time to think.
Along the Bigfoot Trail in the Yolla Bolly-Middle Eel Wilderness
Seeing the trees through the forests, the birds in those trees, and then this vast landscape through my astigmatized-wide-angle glasses; thoughts swirl through my mind. The first few hours allow time to come to terms with my isolation and my body’s age (I’m moving slower than when I was here in my 30’s). Slowly my mind settles into place, in the wilderness. I ponder plant migrations and vegetation patterns as a student of biogeography. A few miles later my mind drifts towards systems of order (and disorder) that are established out here. This is where true place-based interpretations begin to solidify: my understanding of wilderness and how I’ll never truly fit in among it. Then comes the delineation of rarity. I am a rare human here–among the trees, sky and soil–but this fanciful journey is for the rare plants of the Yolla Bolly-Middle Eel.
Manzanitas of San Bruno Mountain County Park – An island of Artctostaphylos endemism
This region is the epicenter for “localized endemism” in manzanitas. Two manzanita species are found on this mountain and nowhere else (A. pacifica and imbricata) and both share space and time with a distinct form of bear-berry (A. uva-ursi), the equally rare Montara Mountain manzanita (A. montaraensis) and the more common brittleleaf manzanita (A. crustacea). The San Francisco Bay area is at the center of the range of biodiversity for the genus Arctostaphylos–which extends from just north of the Oregon-California border southward to northern Baja California, Mexico. Other nearby Bay Area rarities include the Franciscan manzanita (A. franciscana), Presidio manzanita (A. montana ssp. ravenii), and Marin manzanita (A. virgata) to name a few.
Downtown San Francisco, seen from San Bruno Mountain County Park.