Russian Wilderness Forest Communities: A Botanical Perspective - Research Review

August 6, 2016 UPDATE: The California DWF Biogeographical Data Branch forwarded me an updated library of Dr. Sawyer's early research this week. 

There comments were as follows: 

"What you unearthed was work done in the 1960’s[-70's] by John Sawyer and Dale Thornburgh, both former professors at Humboldt State University.   Unfortunately these vegetation descriptions were never developed into a mapping project."

"The last available maps done in the eastern Klamath Province were updated in 2007 and it is not mapped to the detail that would give you polygons directly attributable to the two associations you have mentioned. These are pretty common associations as you have guessed, but without detailed field work and fine scaled mapping the probability of accurately delineating these and other coniferous forest associations is low. My guess is they would have to be delineated using a combinations of cues from topography and forest structure. Not impossible, but so far only done on more local scales in some national parks and other public lands."

The data from the USFS website is the CalVeg data he describes, and it was used above for my GIS ground cover analysis. As mentioned, I should characterize the plant associations in the field so that they are consistent in my plots. I asked them for a key recommendation. (Dr. Sawyer also contributed quite a bit to Terrestrial Vegetation of California, Chapter 10 - Forests of Northwestern California.)

 

After contacting the KNF (Scott River) USFS office and requesting forest community key from the district botanist, she forwarded several high quality references to assist with forest plant identification. Also, Dr. Sawyer, a biologist who has worked extensively in the Sugar Creek Basin since the 1960's, published significant research describing the forest communities of the Russian Wilderness. It comprises four years of fieldwork performed into the early 1970's and is published online by Oregon State University. 

 

The associations he derived were made on the premise that the general "study of montane and subalpine forests of the Klamath Region" suggest "the importance of local disturbance in maintaining high regional [plant bio]diversity." Focusing for this review on the core theme of disturbance and the key forest associations (plant or vegetative communities) within the study area, he concludes that, "local disturbances have created a greater number of varied habitats and individualized species distributions. Existing vegetation patterns are complicated, and the relic populations are maintained. In this manner local history may be even more important than environmental constraints in determining existing patterns."

Although Dr. Sawyer moves into a fair amount of discussion regarding localized climate, and the differences with respect to other key forests in California, our work focuses on microclimate (more about this parameter later) and in the context of a new consensus on climate change in California more broadly, whether it is anthropogenic or cyclic in nature. 

In addition, the methods used to develop forest classifications are somewhat involved for purposes of this review, and may obfuscate the discussion on biodiversity as it is now understood in the context of current landscape ecology. I will leave that for another discussion.

Most useful are the key plant associations from this research that I will look for this month - hopefully holding to 1-3 at most - are as follows:

Types characteristic of the eastern subregion:

1.) Abies concolor/Berberis nervosa - closed forests along streams, mesic slopes.

"The forest description for the Russian Peak area is typical of mesic habitats in the eastern Klamath region. The mixture of canopy species rather than white fir and Douglas-fir dominance, a mingling of mesophytic and xerophytic shrubs and a less developed ground layer distinguish itfrom Ahies concoler/Trillium ovatum and Abies concolor/Vicia americans forests found on comparable habitats in the western subregion. On the drier slopes it merges with Abies concolor/Ceanothus prostratus." 

2.) Abies concolor/Ceanothus prostratus - open- forests of xeric slopes. 

"Described for the Russian Peak area this forest is typical of the eastern Klamath Region on dry, rocky slopes with thin soils. The shrub layer may include Lithocarpus densiflora var. echinoides not found in the Russian Peak stands. Successional trends show a mix of mid-elevation conifers gradually growing through and overtopping montane chaparral. The open, mixed character of the Mature forest allows the light demanding species to continue to reproduce well. The lack of a dense shade stage found in Abies concolor/Chimapila umbellata accounts for the understoy differences between these types with mature forests of similar canopy composition. In addition these forests do not show the more near complete white fir dominance of the relatively more mesic Abies concolor/Chimapila umbellata. 

In his concluding remarks, Dr. Sawyer comments on the nature of vegetation patterns based on topography and seral classification: "If only the mature forests on deep soils are considered, the pattern is readily apparent: a series of elevationally zoned forests dominated by one to several tree species. Within each elevational zone , understory development decreases with increased habitat dryness. Forests rich in herbs and shrubs along the streams give way to simple forests barren of understories on - the dry slopes. The pattern is similar to that of other western mountain areas but is less obvious because of the lack of habitat continuity. In addition to the strong climatic, topographic, and lithic diversity, a variable fire history creates a variety of confusing seral stages. For this reason the understory composition is more indicative of habitat conditions and more regionally consistent than is canopy composition." This is helpful and the pre-analysis for plot siting takes this into account to the best of my knowledge.

Regarding the major takeaway from Dr. Sawyer's research, so that it is not lost in the technical details and discussion of forest associations per se, plant biodiversity in the Russian Wilderness and surrounding areas is unique and significant, and is believed to be the result of many varied historic disturbances from glaciation to major climate shifts that had localized impacts on relic populations. These populations are believed to remain in the area due to the refugia created by the area's diverse topographic features.