Item 7.1 Att 4 (5) Ex A - Final_EACCS_Oct2010_Print - City of Dublin

Chapter 2 Environmental Setting
Northern mixed chaparral/chamise chaparral is classified by Holland (1986) as
“broad-leaved sclerophyll shrubs, 2–4m tall, forming dense, often nearly
impenetrable vegetation… [with] usually little or no understory vegetation [and]
often considerable accumulation of leaf litter.” Northern mixed
chaparral/chamise chaparral appeared darker green in color on aerial photos
than other chaparral types in all seasons, and frequently occupied larger areas.
Ideally, chamise chaparral could be split into a separate land cover type but it
could not be distinguished on the aerial photograph from northern mixed
chaparral.
Dominant shrubs in this community in the study area are chamise, manzanita,
scrub oak, and ceanothus. Other important species are toyon, coffeeberry,
madrone, California bay, birchleaf mountain-mahogany, poison-oak, bush
monkey flower, and California yerba santa. Some chaparral stands may be
almost entirely composed of dense stands of chamise (Holland 1986).
Northern mixed chaparral may intermingle with northern coastal scrub/Diablan
sage scrub, foothill pine and oak woodlands, and mixed oak woodland and
forest. There seems to be a close association between northern mixed
chaparral/ chamise chaparral and foothill pine and oak woodland in the study
area.
Mixed Serpentine Chaparral
Mixed serpentine chaparral occupies an estimated 3,788 acres (1.4%) of the
study area in at least 54 distinct patches (Table 2-4). Nearly all of the mixed
serpentine chaparral is found along Cedar Ridge, between Cedar Mountain and
the Alameda/Santa Clara County line. These stands are large and seem
relatively contiguous on aerial photos. The site specific condition of the habitat
or continuity of the land cover has not been confirmed. A small patch of mixed
serpentine chaparral is located just north of Calaveras Reservoir on the west
side of Alameda Creek. This patch is small and isolated, though there are
patches of northern coastal scrub/Diablan sage scrub in the area (Figure 2-8).
Mixed serpentine chaparral consists of fire-adapted shrubs found on serpentine
soils (California Partners in Flight 2004). Serpentine chaparral is generally more
open than other chaparral types, and shrubs tend to be shorter and have leaves
that are reduced, curled, or thickened (Hanes 1988, California Partners in Flight
2004). Dominant shrubs in this community in the study area are very similar to
those discussed for northern mixed chaparral/ chamise chaparral, above. A
common indicator shrub on serpentine soils is leather oak.
Northern Coastal Scrub/Diablan Sage Scrub
Northern coastal scrub/Diablan coastal scrub occupies an estimated 2,700 acres
(1%) of the study area (Table 2-4). Though this land cover type is spread
throughout the southern part of the county, most of it is concentrated in the
East Alameda County Conservation Strategy 2-41 October 2010
ICF 00906.08