Mount Linn—also called South Yolla Bolly Mountain—is the highest point in the Coast Range of northern California. It is located to the west of Corning but the area might as well be a world away from the population centers of the state; it is rarely noticed by travelers as they drive Interstate 5. Once off the interstate, scenic forest service roads still take nearly 2 hours to wind to the trailhead. Although this place has always been on my list of places to visit—the impetus for this visit was to collect some samples of the rare Sierra juniper (Juniperus grandis) for Robert Adams of Baylor University so that, through DNA testing, he might find out if these trees truly are what we think they are (see previous blog). After a 25 mile sojourn deep into the wilderness to collect those specimens it was time to search for the southern most stand of foxtail pine in northwest California—on Mount Linn.


The distinct cones and "bottle-brush tassle" branches help to identify Pinus Balfouriana.

The highest summit on South Yolla Bolly Mountain is Mount Linn at 8092 feet, but the exposed ridgeline is nearly a mile long hence the two names. Just below the summit of the main peak is a saddle leading to the second highest peak on the ridgeline—this is where a 10 acre grove of one of the most sublime conifers in the world grows. Here at the southern extent for Pinus balfouriana var. balfouriana they are flourishing, if only on a very restricted and specific site. The grove is nearly pure, with only a few Shasta fir (Abies magnifica var. shastensis), western white pine (Pinus monticola) and Jeffrey pine (Pinus jeffreyi) sharing the windswept ridgeline. It is an idyllic place to wander for both the botanical wonders and endless views (Mount Linn is rated as the 10th best view for any mountain in California.)


From the summit of Mount Linn (8092 feet) the grove of foxtail pine can be explored from the obvious saddle—just east of the second highest peak.

Foxtail pines, a California endemic, require a very specific habitat to survive. In northwest California they only grow above 7500 feet on south-facing slopes with a soil substrate that is most often serpentine. When these three factors come together foxtails can flourish. This is also the only population in northwest California that is not in the Klamath Mountains proper (see range map below) but with the lack of competition from other conifers this grove has persisted for millennia.


A foxtail pine dangles from the ridgeline of South Yolla Bolly Mountain—high above the Great Central Valley.

In California, foxtail pines form two distinct populations separated by more than 300 miles. The southern foxtail pines (var. austrina) grow in the southern Sierra Nevada at elevations above 9500 feet where they form pure stands and attain old age. The northern foxtail pines (var. balfouriana) are isolated on sky islands—defined as local mountain tops and ridgelines—found in the eastern half of the Klamath Mountains and this one spot in the North Coast Range. Here, proper geologic and climatic conditions allow them to compete with the shade-tolerant and faster growing firs and hemlocks (Eckert 2006). This elevational requirement, coupled with soil conditions and drier climate, has allowed isolated populations to persist in the Klamath region after upwards of one million of years of evolutionary divergence between these subspecies (Eckert et al. 2008).


A range map for the foxtail pine (Pinus balfouriana var. balfouriana) in northwest California.

References and Resources:

1. Earle, Christopher J., Forest Ecologist, “The Gymnosperm  Database”, <http://www.conifers.org>, 9043 Dibble  Ave., NW , Seattle, WA 98117
2. Eckert, A. J. 2006. Influence of substrate type and microsite  availability on the persistence of foxtail pine (Pinus balfouriana, Pinaceae) in the Klamath Mountains, California. American Journal of Botany 93: 1615-1624
3. Eckert, A. J., B. R. Tearse, and B. D. Hall. 2008. A phylogeographic analysis of the range disjunction for foxtail pine (Pinus balfouriana, Pinaceae): the role of Pleistocene glaciation. Molecular Ecology.