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.
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.
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.
Walker Ridge has been on my plant exploration list for many years. I had repeatedly heard about the rare plants, serpentine landscape, and epic wildflower displays that could be found along the ridge and in the adjacent Bear Valley. I also read about a proposal to designate the region as Serpentine National Park which, at the time, was a radical approach to try to halt a major wind turbine project slated for the ridgeline. I was excited to finally explore this place and to locate what has been called the largest stand of McNab cypress in the world. What I found was something entirely different.
Looking north toward Walker Ridge from the access road.
A sequence of five elevated marine terraces along Jug Handle Creek in coastal Mendocino County constitutes a nationally and internationally famous ecological staircase. So outstanding is the combination of canyons, terraces and ancient dunes, tall redwoods and firs, bishop pine forest and dwarfed pines and cypresses that…It has become a Mecca for naturalists, botanists, ecologists, pedologists (soil scientists), geographers and nature-oriented laymen. It is being praised as the best preserved ecological showplace of coastal landscape evolution anywhere in the northern hemisphere.
–Hans Jenny 1973
Throughout the Pleistocene, as the climate fluctuated, sea levels rose and fell in conjunction with the size of the polar ice caps thus allowing oceanic wave-action to cut coastal terraces around the world. Subsequent tectonic forces then slowly pushed these terraces upward. What we now witness in coastal Mendocino County is, as Jenny states, the best preserved ecological showplace of coastal landscape evolution in the Northern Hemisphere.
Mendocino Ecological Staircase
Through other dynamic processes, beach materials like sand, gravel, clay and other rock have been deposited on the terraces at varied depths. Directly adjacent to the Pacific Ocean on the first step, wind sculpts coastal scrub and grassland on coastal bluffs or “Bonsai” beach and bishop pine forests just inland. A bit further up the staircase, out of reach of the salty air, ample precipitation, Pleistocene and Holocene sand dunes, and deposition of nutrient-rich conifer needles offers the abiotic needs for trees with deep roots and tall shoots. However, the most amazing staircase story begins just to the east of the ancient dunes.
