Chapter 2

Chapter 2 – Mountain and Foothills Ecosystems

To understand the fashion of any life, one must know the land it is lived in and the procession of the year. — Mary Austin (1903) Key Questions • What are the major ecological known multitude of invertebrate animals and communities in the coastal nonvascular plants. We know very little about mountains of southern California? the specific habitat needs of the majority of • What is known about the status and these species. So how do we address all of this distribution of each? biological diversity in a feasible manner? Until recently, wildlife management • How have they changed in the last tended to focus on the needs of a few, high- 100 to 200 years? profile species (mostly game animals and • What rare communities exist and endangered species). Now the potential im- what are their status and trends? portance of all members of an ecosystem has been recognized and the focus has shifted away This chapter provides a large-scale over- from single-species management and towards view of landscape patterns and ecological ecosystem-based conservation (Hansen et al. communities within the assessment area. A 1993; Manley et al. 1995; Haufler et al. 1996). more detailed description of the specific eco- The idea that conserving broad ecological logical processes and human land uses affecting communities may be the most efficient way these ecosystems is presented in chapter 3. to maintain species diversity has gained wide- Here we focus on the extent and distribution spread acceptance and is implicit in the of each type, its current condition, and its rep- so-called coarse-filter approach (Noss 1987). resentation on public lands across the different Originally developed by The Nature Con- mountain ranges. Much of this information servancy, the coarse-filter approach assumes that is based on our GIS vegetation data. How- a representative array of ecological communities ever, first we describe the coarse-filter analysis will sustain the vast majority of species, includ- approach that is a major component of this ing many of the ones we know little about (fig assessment. 2.1)(Hunter et al. 1988). By relying on reten- tion of community types and providing an array The Coarse-Filter, Habitat- of structures and compositions, we hope to “cap- ture” most of the diversity in the system. Based Approach However, we know that some species, subspe- According to the California Wildlife Habi- cies, and rare communities have characteristics tat Relationships System (CWHR, version that make them “fall through the mesh” of the 5.2) and the California Flora Database coarse filter and these need special attention (i.e., (CALFLORA), the mountains and foothills a finer filter). The fine-filter approach focuses of southern California are inhabited by 18 on learning the specific needs of individual spe- amphibian, 61 reptile, 299 bird, 104 mam- cies and then providing for those needs, mal, and 2,900 vascular plants species (CDFG potentially through intensive management. 1996; Dennis 1995). Added to that is an un- 15 sarily require specific management attention. Rather, it suggests that their status and needs warrant individual consideration before decid- ing on a course of action. Based on the fine-filter screening criteria, 184 animals and 256 plants made the focal species list. These species are addressed in chapters 4 and 5, “Species at Risk,” and chap- ter 6, “Species of High Public Interest.” All other plants and animals occurring within the assessment area will only be addressed indi- rectly, via the coarse-filter, community-level analysis. The coarse-filter analysis procedure is quite simple: Current conditions are compared to reference conditions (based on how the landscape would look and function if people were not altering it), differences between the two are identified, the significance of the change is analyzed, and this information is fed into the decision-making process. However, the application of these ideas can be quite com- plicated (Sampson et al. 1997). Figure 2.1. The coarse-filter approach to The reference conditions represent our maintaining biological diversity focuses on best attempt to describe the ecological condi- protecting a representative array of communities tions, including their variability over space and and is based on the assumption that these time, under which native species evolved. If communities will encompass the vast majority of species. The fine-filter approach focuses on saving individual species that slip through the coarse filter. Figure 2.2. Fine-filter criteria used to identify As illustrated here, the coarse filter has been used species that should receive individual consideration to save a tract of Zaire’s forest, while the fine-filter in this assessment. A species or subspecies made approach has been employed for the pygmy the list if it met one or more of the criteria. chimpanzee and Congo peafowl (from Hunter et al. 1988). Species Potentially at Risk: ¥ A Threatened, Endangered, or Proposed In this assessment we employed a com- Species (federal and state) bined coarse-filter/fine-filter approach. ¥ A former USFWS Candidate (C1 or C2) Species Fine-filter criteria were used to identify spe- ¥ A Forest Service, Region 5 Sensitive Species cies that would receive individual consideration (fig 2.2). The criteria primarily ¥ A California Species of Special Concern target species that are rare and vulnerable. ¥ A Riparian Obligate Species of Concern (as However, we also identified species that have defined by California Partners in Flight) a heightened status due to the high public in- ¥ A species determined to have viability concerns terest that they generate. Thus, the fine-filter at a local level list is really divided into two distinct catego- Species of High Public Interest: ries: (1) species potentially at risk and (2) ¥ A major game animal species of high public interest. Each species ¥ A species that has particular public interest (e.g., identified in the fine-filter list does not neces- mountain lion)

16 Chapter 2 today’s conditions are similar to the reference In between the patches and corridors is the conditions, we are confident that adequate habi- surrounding matrix — a dominant vegetation tat is present for most species. The greater the or land type, such as chaparral in the foothills deviation from the reference conditions, the more or urbanized land in the Los Angeles Basin. species may be at risk. (Sampson et al. 1997). Across the southern California mountains An inherent difficulty with this approach and foothills region there are a few broad-scale is that it is usually difficult to determine the landscape mosaics that are clearly recognizable “true” reference conditions and the natural and repeatedly encountered. In the coastal range of variability. They must be inferred foothills the matrix is coastal scrub and chap- based on our knowledge of historic habitat arral interspersed with riparian corridors, oak conditions and on our understanding of key woodlands, and grasslands. Above the foot- ecological processes such as fire, succession, hills on often-steep lower mountain slopes, the and flooding. Since the historic record is fre- mosaic shifts to patches of mixed hardwood/ quently sketchy and inconclusive, there are conifer forest scattered between large expanses usually several plausible theories on how the of chaparral. As you move into the upper historic landscape might have looked and mountain region, pine and fir forests domi- functioned. nate the landscape and are punctuated with These problems are compounded by the patches of black oak woodland, montane fact that we will often be managing outside meadows, and chaparral. On the desert side the range of conditions that native species of the mountain crest is another distinct land- encountered in the past. In some places, the scape, dominated by sparse pinyon forests, ecological systems are so altered that we will juniper woodlands, desert scrub, and exten- typically be outside the range of conditions sive areas of bare rock. that occurred historically (e.g., in dammed Key physical factors that seem to trigger river systems or in grasslands that are now broad-scale changes in the vegetation mosaic dominated by non-native species). Social con- are elevation, distance from the coast, topog- siderations (e.g., reducing fire hazards near raphy, and position on either the coastal or towns) and economic factors also affect our desert side of the mountain crest. These fac- ability to remain in (or move toward) more tors have a strong influence on precipitation “natural” landscapes. The farther we move amounts and temperature regimes, which in from those conditions, the less successful we turn greatly influence the type of vegetation can expect the coarse-filter approach to be that grows. Today, human land use also plays (Sampson et al. 1997). a key role in shaping these land mosaics. Despite these difficulties, the coarse filter Below we describe and present a map (fig. can be an effective approach for (1) retaining 2.3) of the six large-scale vegetation mosaics biological diversity in its broadest sense, (2) that characterize the mountains and foothills retaining critical but little understood pro- of southern California. In reality these mosa- cesses (such as roles played by soil microbes), ics, or “landscapes” as we refer to them here, and (3) sustaining species that we currently do not have distinct boundaries but rather have know little about. broad transition zones where different vegeta- tion assemblages intergrade. However, each Broad-Scale Landscape landscape has unifying characteristics that have important implications for resource manage- Mosaics ment. These characteristics transcend the From an airplane, land usually appears as particulars of which mountain range or wa- a mosaic of patches, corridors, and matrix tershed the landscape may be found in. There (Forman 1995). Woodlands, fields, and hous- are clear differences in the way each landscape ing tracts often stand out as conspicuous type has historically been affected and shaped patches. Rivers form equally striking corridors. 17 by fire, human habitation (both Native Ameri- Table 2.1. The mix of dominant vegetation types can and early European), and other natural in the foothills landscape. processes. There are also differences in the way each landscape has been affected by recent Vegetation Type Acres % of Foothills activities, such as the last eighty to one hun- dred years of active fire suppression and rapid Chaparral 1,407,079 55% human population growth. Because of the Grassland/ unique vegetation patterns in each landscape oak savanna 351,930 14% there are also clear distinctions in the land use Coastal scrub 323,250 13% activities that take place today in each of them. Oak woodland 268,542 11% Coastal Foothills Landscape Development/ The foothills range from approximately agriculture 112,099 4% 800 to 3,000 feet in elevation on the coastal Other 81,890 3% side of the mountains. In San Diego County, foothill vegetation patterns extend up to 4,000 Total: 2,544,790 feet in some places. Although topographically varied, the foothills are distinguished by many est (table 2.1). Oak woodlands and savannas miles of relatively gentle hilly terrain. Rolling become increasingly abundant in the foothills hills, plateaus, and broad valleys are common. as you move north. This landscape is most ex- Chaparral is the most common vegetation, but tensive in the Coast Ranges (southern Santa the foothills are also characterized by oak sa- Lucia Range, southern Los Padres region), and vannas and woodlands (fig. 2.4), coastal sage the southern Peninsular Ranges (Santa Ana scrub, and corridors of riparian hardwood for- Mountains, San Diego region).

Figure 2.4. Looking south from Palomar Mountain, Cleveland National Forest, you see a typical foothill landscape: oak woodlands and savannas surrounded by chaparral-covered hills. CNF FILE PHOTO

18 Chapter 2 Lower Montane Landscape The lower montane landscape encom- Table 2.2. The mix of dominant vegetation types in the lower montane landscape. passes mountain slopes from approximately 3,000 to 5,000 feet elevation on the coastal Vegetation Type Acres % of Lower side of the ranges. This mosaic is character- Montane ized by frequently steep and rugged topography. Chaparral dominates the hillsides Chaparral but is interspersed with patches of forest, pri- or scrub 1,181,995 72% marily in canyons and on north-facing slopes Bigcone Douglas-fir/ (table 2.2). Forest types are typically a coni- Coulter pine/ fer/hardwood mix. The most prevalent canyon oak 272,649 17% conifers are bigcone Douglas-fir, Coulter pine Oak woodland 102,979 6% (fig 2.5), and incense-cedar, all of which oc- Grassland/savanna 35,159 2% cur primarily in mixed stands with canyon or Mixed conifer 28,966 2% coast live oak. Stands of black oak also occur, Other 25,560 2% particularly at the upper elevations. Most of the conifer trees in this landscape are endemic Total: 1,647,308 to southern California and northern Baja (i.e., Coulter pine, bigcone Douglas-fir, Tecate cy- press, Cuyamaca cypress and Sargent cypress).

Figure 2.5. The Agua Tibia Wilderness, Cleveland National Forest, is a typical lower montane landscape. Dense patches of bigcone Douglas-fir occupy steep canyons surrounded by chaparral. CNF FILE PHOTO

19 Montane Conifer Landscape Table 2.3. The mix of dominant vegetation types The montane conifer landscape (fig. 2.6) in the montane conifer landscape. extends from approximately 5,000 to 8,500 feet in elevation and is dominated by pine and Vegetation Type Acres % of Montane fir forests (table 2.3). Stands of black oak are Conifer also interspersed. In some areas near the lower elevational limit, oaks are as abundant as co- Pine or fir forest 379,304 76% nifers. As the elevation rises, dominance in the Montane chaparral 77,338 16% conifer overstory shifts from ponderosa pine Oak woodland 20,919 4% to Jeffrey pine to white fir. Black oak declines Meadows/sagebrush 15,434 3% in abundance as elevation increases and as you Other 6,121 1% move from the coastal side to the desert side of the mountains. Sugar pine and incense-ce- Total: 499,116 dar are secondary components in many stands. Montane meadows and chaparral are also in- terspersed. Towards the desert side of the mountains, western juniper becomes a com- ponent of pine and mixed conifer stands all the way up to 8,500 feet.

Figure 2.6. This view from Brush Mountain looking towards Mount Abel, Los Padres National Forest, shows several types of montane conifer forest. The open Jeffrey pine stand on Brush Mountain is typical of arid, high-country forests on the desert side of the mountains. The dense forest blanketing the north slope of Mount Abel is typical of upper elevation mixed conifer. J.D. BITTNER

20 Chapter 2 Desert Montane Landscape Table 2.4. The mix of dominant vegetation types in The desert montane landscape covers a the desert montane landscape. wide elevation range (approximately 3,000 to 7,000 feet) but is often a narrow transition Vegetation Type Acres % of Desert zone between the mountains and the desert. Montane Pinyon pine and juniper woodlands (fig. 2.7), scrub oak chaparral (e.g., Tucker oak), red Pinyon or shank chaparral, and desert scrub are the pre- juniper woodland 346,594 36% dominant vegetation types (table 2.4). In this Semi-desert arid landscape, plant communities generally chaparral/scrub 219,658 23% provide sparse cover with a lot of bare ground Mixed and red shank in between. This mosaic is most extensive in chaparral 130,391 14% the lower elevations surrounding Mount Buckwheat, grass, Pinos, along the northern slopes of the San barren 122,926 13% Gabriel and San Bernardino mountains, and Conifer or oak forest 29,904 3% along the eastern slopes of the San Jacinto Other 27,709 3% Mountains.

Total: 955,592

Figure 2.7. This view to the northeast of Baldwin Lake, San Bernardino National Forest, shows pinyon pine woodlands and sagebrush flats that are characteristic of the desert-side montane landscape. LYNN LOZIER

21 Subalpine/Alpine Landscape Table 2.5. The mix of dominant vegetation types The subalpine/alpine landscape occurs at in the subalpine/alpine landscape. elevations above 8,500 feet. It covers a very small portion of the southern California Vegetation Type Acres % of mountains found only on the summit of Subalpine Mount Pinos and in the highest reaches of the San Gabriel, San Bernardino, and San Subalpine conifer Jacinto ranges. Subalpine and alpine habitats forest 8,229 53% are most extensive on the high slopes of Mixed coniferÐfir 2,504 16% Mount San Gorgonio and Mount San Jacinto Montane chaparral/ (fig. 2.8). The primary plant community is scrub 2,890 19% subalpine forest (table 2.5) that consists of Alpine or barren 1,913 12% white fir, lodgepole pine, and limber pine. Other 68 0% These are often relatively sparse forests char- acterized by small diameter trees. A rare and Total: 15,604 fragile alpine cushion plant community oc- curs above treeline. Monterey Coast Landscape The Monterey coast landscape (fig. 2.9) Figure 2.8. Sparse stands of limber pine on the occurs only along the coastal slopes of the upper slopes of Mount Baden-Powell, Angeles northern Santa Lucia Range. It is character- National Forest, are characteristic of subalpine ized by the southernmost occurrence of coastal forests near timberline. ANF FILE PHOTO redwood forest, and the southernmost con- centrations of Douglas-fir and Pacific madrone (table 2.6). Santa Lucia fir is also endemic to this region. These are low-eleva- tion (sea level to 4,500 feet), mesic forests similar in composition and structure to for- ests along the northern California coast. They are distinctly different from the montane co- nifer forests found at higher elevations in the rest of the assessment area.

Table 2.6. The mix of dominant vegetation types in the Monterey coast landscape.

Vegetation Type Acres % of Monterey Coast

Chaparral/scrub 35,264 35% Redwood/ conifer forest 32,369 32% Oak or bay forest 25,466 25% Grassland/ savanna 6,751 7% Other 22 <1%

Total: 99,872

22 Chapter 2

Figure 2.9. The northern Santa Lucia Range rises dramatically above terraces along the Monterey coast. The coastal slopes of these mountains support the southernmost stands of coast redwood forest. JEFF KWASNY

Major Ecological Savanna woodlands are characterized by widely scattered trees with grass or coastal Communities scrub in between (fig. 2.11). These savannas Many different vegetation types occur contain coast live oak but are more typified along the southern and central California coast by blue or valley oak in the north and Engel- (table 2.7). Most of these extend into the mann oak in the south. Savanna woodland mountains and foothills to some degree. In types are less extensive and more concentrated this section, we describe the distribution, char- on private lands (table 2.8). Engelmann oak, acteristics, and status of the dominant valley oak, and California walnut woodlands vegetation communities. are considered rare communities in our assess- ment area because of limited distribution and Foothill Oak Woodlands poor representation on public lands (Scott Foothill woodlands tend to occur in two 1990). distinct forms: as closed-canopy stands in can- Livestock production has long been the yons or along streams, and as open savannas principal economic activity in foothill wood- in broad valleys and rolling hills. Closed- lands (Pavlik et al. 1991). Most of the private canopy stands have a dense overstory of trees land is consolidated in ranches that vary in with little space between the crowns (fig. size from less than a hundred to many thou- 2.10). Coast live oak is usually the dominant sands of acres. Grazing allotments have been tree in these dense woodlands. Closed-canopy in place for many years on national forest sys- coast live oak woodlands are widely distrib- tem lands and are particularly common in oak uted in the foothills and better represented savanna types. On national forest system lands, on public lands than the open savanna wood- 60 percent of Engelmann oak woodlands and lands (table 2.8). 23 Table 2.7. The vegetation types occurring along the southern and central California coast and associated series-level plant communities as described and numbered in Sawyer and Keeler-Wolf (1995). The primary types are crosswalked from CWHR and CALVEG calssifications.

Vegetation types Douglas-fir/tan oak 250 Series Redwood 300 (from Sawyer & Keeler-Wolf 1995) Santa Lucia fir 302 Cypress and coastal pine Hardwood Forests and Woodlands From sea-level to 5,500 ft. Uncommon, localized habitats. Cypress forest ValleyÐfoothill woodlands Cuyamaca cypress 333 From sea-level to ~3,600 ft. Gowen cypress 337 Monterey cypress 340 Oak woodland Sargent cypress 303 Usually open, savanna-like woodlands with grass Tecate cypress 345 below. Or along streams or north slopes. Blue oak 230 Coastal pine forest Coast live oak 241 Bishop pine 225 Engelmann oak 253 Monterey pine 280 Valley oak 312 Torrey pine 346 Walnut woodland Lower montane conifer/hardwood California walnut 238 From ~3,000 to 5,500 ft. Stands frequently patchy and ValleyÐfoothill riparian surrounded by chaparral. They intermix with montane conifer From sea-level to ~4,500 ft. in canyons and flood plains. at upper elevations. Live oak understory is common. Stands usually denser than upland woodlands, but narrow. Foothill pine/oak forest Riparian forest Usually open stands, conifers even-aged, shrubs or Black cottonwood 226 grass below. Black willow 229 Coulter pine 243 California bay 234 Coulter pine/canyon live oak 244 California sycamore 237 Foothill pine (grey, foothill,digger) 257 Coast live oak 241 Knobcone pine 269 Fremont cottonwood 259 Bigcone Douglas-fir forest Mixed oak 277 Usually dense, multi-layered stands on steep slopes in Red willow 299 canyons. Red alder (north central coast only) 295 Bigcone Douglas-fir 222 White alder 319 Bigcone Douglas-fir/canyon live oak 223 Riparian scrub Montane conifer Arroyo willow 219 From ~5,000 to 8,500 ft. Buttonbush 119 Mixed conifer Ð pine/oak phase Mexican elderberry 171 Jeffrey/ponderosa/sugar pines, live oak, black oak and Mixed willow 279 incense cedar. White fir present, but seldom dominant. Mulefat 179 Oaks common in most of this type and are the dominant Narrowleaf willow 180 stand component in some areas (e.g. the southern Pacific willow 287 Peninsular ranges). Sitka willow 307 Jeffrey pine/ponderosa pine 268 Tamarisk 203 Incense-cedar 263 Montane upland hardwoods Mixed conifer 275 From ~3,000-8,000 ft. Occur in pure stands, but more often Jeffrey pine associated with conifers. Upland live oak stands often consist Open Jeffrey pine stands with few associated species. of low, shrubby trees. Black oak, white fir and western juniper can be present. Black oak 227 In cold, dry, high-elevation sites. Mostly eastern slopes. California buckeye 235 Jeffrey pine 266 Canyon live oak 239 Mixed conifer Ð white fir phase Interior live oak 264 White fir codominate with sugar and Jeffrey pine. Black Mixed oak 277 oak or live oak common in some stands. Occurs in Montane riparian hardwoods mesic, high-elevation sites. From ~3,600-8,000 ft. In canyons and along streams. Riparian Mixed conifer 275 live oak stands consist of tall trees with spreading crowns. White fir 321 Aspen (1 grove, San Bernardino Mts) 220 Subalpine conifer forests California bay 234 From 8,500 to >10,000 ft. Canyon live oak 239 Limber pine 270 Interior live oak 264 Lodgepole pine 271 White alder 319 Mixed subalpine forest 278 Pinyon/juniper woodlands Conifer and Conifer/ Hardwood Forests From ~3,000 to 8,500 ft. on arid desert-facing slopes. California juniper 236 North Central Coast Range forests Mountain juniper 283 These occur only in the northern portion of the Central Coast Parry pinyon (four needle) 288 Ecoregion, including the Monterey District of Los Padres NF. Singleleaf pinyon 304 Douglas-fir 246 Western juniper 316 Douglas-fir/ponderosa pine 249 Shrublands and Chaparral Live oak scrub Int. live oak scrub 161 Coastal scrub Int. live oak/cyn. live oak scrub 163 From sea-level to ~3,600 ft. “Soft chaparral.” Shrubs not very Int. live oak/whitethorn scrub 164 woody and stands more open than in chaparral types. Int. live oak-scrub oak scrub 165 Black sage 109 Interior/desert scrub California buckwheat 120 From ~3,000 to 7,000 feet on desert-side of the mountains. California buckwheat/white sage 122 These shrublands are generally sparser than those on coastal California encelia 123 slopes. California sagebrush 124 Big sagebrush 100 Calif. sagebrush/black sage 126 Black bush 108 Calif. sagebrush/Calif. buckwheat 127 Black sagebrush (Big Bear pebble plains) 110 Coast prickly-pear 141 Bladderpod-CA ephedra- Coyote brush 142 narrowleaf goldenbush 111 Mixed sage 172 Brittlebush 114 Purple sage 184 CA buckwheat-white sage 122 Salal-black huckleberry 191 Creosote bush 144 Scalebroom 193 Creosote bush-white bursage 145 Chaparral Cupleaf ceanothus/fremontia/oak 146 From sea-level to 5,000 ft. Woody shrubs in stands that Fourwing saltbush 153 usually become very dense when mature (>10 yrs old). Joshua tree 168 Coastal maritime chaparral Mohave yucca 175 Nolina 181 Chamise/black sage 133 Rubber rabbitbrush 189 Leather oak 169 Scrub oak 194 Woollyleaf manzanita 211 Shadscale 199 Sumac 202 White sage 208 Chamise chaparral Chamise 130 Chamise/black sage 133 Grasslands, Meadows & Herbaceous Types Chamise/white sage 139 Southern mixed chaparral Grasslands Chamise/mission manzanita/ Alkali sacaton 30 Woollyleaf ceanothus 137 Creeping ryegrass 47 Desert needlegrass 50 Northern mixed chaparral Foothill needlegrass 55 Bigberry manzanita 102 Nodding needlegrass 67 Bigpod ceanothus 103 California annual grassland 40 Bigpod ceanothusÐ One-sided bluegrass 68 birchleaf mt. mahogany 104 Purple needlegrass 75 Bigpod ceanothusÐhollyleaf redberry 105 North central coastal prairie Birchleaf mt mahogany/CA buckwheat 106 Blue blossom 112 Cal. oat grass 42 Chamise/bigberry manzanita 132 Idaho fescue 59 Chamise/cupleaf ceanothus 134 Introduced perennial grassland 61 Chamise/eastwood manzanita 135 Pacific reedgrass 69 Chamise/hoaryleaf ceanothus 136 Tufted hairgrass 88 Chamise/wedgeleaf ceanothus 138 Meadows Eastwood manzanita 151 Alkali sacaton 30 Chaparral whitethorn 140 Montane meadow 353 Hoaryleaf ceanothus 157 Nebraska sedge 65 Wedgeleaf ceanothus 206 Sedge, shorthair sedge 82,85 Holly leaf cherry 339 Subalpine meadow 356 Redshank chaparral Alpine Redshank 185 Alpine habitat 349 RedshankÐbirchlf. mt. mahogany 186 Sedge 82 RedshankÐchamise 187 Subalpine upland scrub 357 Scrub oak chaparral Seeps/bogs/marsh/vernal pools Scrub oak 194 Scrub oakÐbirchleaf mt. mahogany 196 Bulrush, bulrush-cattail 35, 37 Scrub oakÐchamise 197 Bur-reed 39 Scrub oakÐwhitethorn 198 Cattail 43 Mixed scrub oak 174 Ditch-grass 52 Duckweed 53 Montane chaparral Montane wetland scrub 355 From 4,000 to 10,000 ft. Characterized by absence of chamise Mosquito fern 63 and presence of species found only in the mountains. Usually Pondweeds 73, 74 dense and woody. Quillwort 76 Bush chinquapin 117 Saltgrass 78 Canyon live oak shrub 128 Spikerush 86 Deerbrush 148 Subalpine wetland shrub 358 Greenleaf manzanita 155 Vernal pools Mountain whitethorn 178 Montane vernal pools (not in Sawyer) Huckleberry oak 160 San Diego Mesa vernal pools 369 Tobacco brush 205 San Jacinto Valley vernal pools 370 Santa Rosa Plateau vernal pools 371 ability to manage fire on the landscape be- comes more constrained. Second, the decline of high-quality oak woodlands on private lands increases the significance of such habitats on public lands. Finally, the decline of ranching in this region, particularly in the southern counties, is gradually reducing the amount of livestock grazing on public land. Other factors affecting ecosystem condi- tion in foothill savanna woodlands include the spread of non-native species (particularly Figure 2.10. This coast live oak stand in the San Mediterranean annual grasses) and oak regen- Mateo Wilderness, Cleveland National Forest, is eration problems. Introduced annual grasses characteristic of dense foothill woodlands frequently grow rapidly during spring and deplete sur- found in canyons and along streams. ANNE FEGE face water much earlier in the season than the displaced native perennial grasses (Pavlik et al. 87 percent of blue oak woodlands are within 1991). This diminishes water supplies to oak grazing allotments. seedlings. Blue, valley, and Engelmann oak are Over the past twenty years, an increasing not regenerating well in many savanna wood- number of large foothill ranches have been lands (Holland 1976; Scott 1990). This does subdivided and converted into ranchette-style not appear to be the result of one single factor housing developments. This trend is expected but rather the combined effect of non-native to continue and perhaps intensify in the com- grasses, grazing, and an unnatural abundance ing decade, particularly in the southern of acorn-eating animals such as gophers and counties where demand is greatest (i.e., San ground squirrels (Borchert et al. 1989; Diego, Riverside, Ventura, and Santa Barbara Schoenherr 1992). counties). The closed-canopy coast live oak wood- The trend towards increased development lands are less threatened. Regeneration does of foothill woodlands has several clear impli- not appear to be a problem and coast live oak cations for public land management. As the is a vigorous crown sprouter after fires. urban interface expands and increasingly sur- rounds public wildlands, demand for Cismontane Scrub and Chaparral recreation and other facilities increase and the Coastal scrub and chaparral are the domi- nant ecological communities on the coastal Figure 2.11. This blue oak stand on the Los Padres side of the mountains below 5,000 feet. National Forest is characteristic of the oak savannas Coastal sage scrub occurs primarily at eleva- and woodlands found in broad valleys, rolling hills tions below 2,500 feet and is most widespread and mesa tops. MARK BORCHERT in coastal valleys and plains west of the foot- hills. Chaparral occurs across a broad elevational range but is particularly abundant in lower montane and foothill areas. Coastal sage scrub consists of drought- deciduous, soft-leaved shrubs, frequently dominated by California sagebrush, buck- wheat, and several sage species (fig 2.12) (Mooney 1977). The extent of coastal sage scrub has been greatly reduced by conversion to agricultural, industrial, and residential land

26 Chapter 2

Table 2.8. Acres of foothill oak woodland by mountain range. Values in parentheses are the percentage of those acres occurring on public lands. These figures represent land area where the specified vegetation type is dominant. They are derived from a large-scale GIS vegetation layer that combines data from several different mapping efforts (see “Information Sources” section, chapter 1.)

Cleveland NFSan Bernardino NF Angeles NF Los Padres NF Acres of Foothill Woodland San Santa San San San Castaic S. Los S. Santa N. Santa Vegetation Types Diego Ana Jacinto Bernar- Gabriel Ranges Padres Lucia Lucia Ranges Mts Mts dino Mts Mts Ranges Rng Rng TOTAL

Coast live oak woodland 44,243 10,181 2,153 18 11,177 4,178 86,073 88,384 76,976 323,476 (30%) (56%) (52%) (66%) (62%) (51%) (30%) (89%) (52%)

Blue oak woodland 1,483 31,487 88,409 9,104 130,483 (22%) (45%) (33%) (63%) (38%)

Engelmann oak woodland 17,054 4,029 21,083 (5%) (45%) (12%)

Valley oak woodland 410 388 7,699 8,497 (3%) (8%) (8%) (8%)

CA walnut woodland 30 3,896 3,926 (100%) (1%)

Alvord oak woodland 1,617 1,617 (4%) (4%)

TOTAL 61,297 14,210 2,313 18 11,207 6,071 121,844 184,492 87,697 489,082 (23%) (53%) (52%) (66%) (48%) (48%) (31%) (84%) (45%)

use (Davis et al. 1994; O’Leary 1990). It is However, our assessment area encompasses now found in only about 15 percent of its only the upper elevational limits of coastal former range in southern California (Westman scrub where some of the associated rare spe- 1981; O’Leary 1990). The remnant stands of cies, including the gnatcatcher, are less coastal sage scrub are habitat for a growing abundant or absent. number of endangered taxa such as the Cali- A major factor affecting ecosystem health fornia gnatcatcher (Davis et al. 1994). in coastal sage scrub is fire frequency. This type of vegetation burns easily and is capable of Figure 2.12. Coastal sage scrub, like this area in reburning only one or two years after a previ- Riverside County, is dominated by soft-leaved ous fire. Frequent reburns result in the shrubs. JAN BEYERS conversion of these shrublands to annual, non- native grasslands (Zedler et al. 1983) (fig 2.13). Since this ecosystem is increasingly adjacent to or surrounded by the urban interface, it is becoming more difficult to prevent frequent fires and subsequent habitat degradation. Chaparral consists of evergreen, woody shrubs (e.g., chamise, manzanita and ceanothus) (fig. 2.14). There are many types of chaparral (table 2.7) and they vary widely in species composition (Gordon and White 1994). In general, chaparral is abundant in the 27 assessment area and well represented on pub- shrub species use to survive in a fire-prone en- lic lands (table 2.9). Only a few chaparral vironment. Some species are short-lived, others associations are considered relatively rare and long-lived. Some rely primarily on resprouting poorly represented on public lands: southern after fire; others regenerate primarily from seed mixed chaparral, ceanothus chaparral, and ser- (Keeley 1986; Zedler 1995). These strategies pentine chaparral. affect a species’ resilience to changing fire re- Fire regimes are the primary ecosystem gimes. However, studies suggest that most health issue in chaparral and much has been chaparral shrubs appear to be resilient to fire- written on the subject (see Keeley and Scott return intervals of anywhere from twenty-five to 1995). The frequency, seasonality, size, and in- one hundred years (Keeley 1986; Zedler 1995). tensity of fires are all important. There are a The natural fire-return interval in chapar- variety of different life history strategies that ral is a widely debated issue, but recent research

Table 2.9. Acres of cismontane chaparral and scrub by mountain range. Values in parentheses are the percent of those acres occurring on public lands. These figures represent land area where the specified vegetation type is dominant. They are derived from a large-scale GIS vegetation layer that combines data from several different mapping efforts (see “Information Sources” section, chapter 1.)

Cleveland NFSan Bernardino NF Angeles NF Los Padres NF Acres of Cismontane Chaparral and Scrub San Santa San San San Castaic S. Los S. Santa N. Santa Diego Ana Jacinto Bernar- Gabriel Ranges Padres Lucia Lucia Vegetation Ranges Mts Mts dino Mts Mts Ranges Rng Rng TOTAL

Coastal sage scrub 32,960 28,174 2,664 18,091 31,397 65,714 91,028 21,181 22,418 313,627 (25%) (33%) (2%) (14%) (51%) (19%) (52%) (37%) (58%) (38%)

Buckwheat/white sage 28,267 5,891 7,706 23.044 5,058 33,707 105,082 353 209,108 (52%) (90%) (58%) (55%) (69%) (68%) (78%) (84%) (69%)

Northern mixed chaparral 217,080 103,172 41,092 81,654 253,302 136,663 635,929 132,205 184,195 1,785,649 (60%) (80%) (80%) (79%) (90%) (86%) (89%) (78%) (88%) (83%)

Southern mixed chaparral 71,550 5,994 77,544 (38%) (15%) (36%)

Chamise chaparral 130,146 54,112 39,979 33,735 32,183 57,994 64,040 68,286 53,988 534,463 (49%) (61%) (51%) (54%) (84%) (63%) (66%) (42%) (63%) (57%)

Scrub oak chaparral 33,446 7,016 384 15,999 443 5,317 18,003 5,482 3,267 89,357 (67%) (89%) (92%) (62%) (86%) (9%) (84%) (89%) (55%) (69%)

Montane chaparral 13,252 121 3,928 28,163 23,416 17,944 86,824 (52%) (100%) (73%) (90%) (99%) (99%) (88%)

Redshank chaparral 107,078 106,576 213,654 (66%) (61%) (63%)

Ceanothus chaparral 1,147 409 333 14,932 3,830 2,583 23,234 (18%) (52%) (18%)

Serpentine chaparral 7,473 7,473 (17%) (17%)

TOTAL 633,779 204,480 202,329 201,903 346,316 299,728 946,958 231,337 273,924 3,340,754 (54%) (68%) (62%) (66%) (86%) (63%) (82%) (62%) (78%) (71%)

28 Chapter 2 or not, large fires tend to create a homoge- neous vegetation pattern, with large tracts of brush in a single age class. This simplified age- class mosaic, while not a problem for the shrubs themselves, reduces habitat diversity, which generally leads to a reduction in wild- life diversity. Game animals like quail and deer, which tend to be habitat edge species, gener- ally avoid large, unbroken tracts of chaparral. The continuous fuels also may make large fires more likely to recur. Figure 2.13. Coastal sage scrub that reburns several times in rapid succession becomes degraded and dominated by non-native, annual grasses. JAN BEYERS Lower Montane Forests Bigcone Douglas-fir, Coulter pine, canyon suggests a typical interval of fifty to seventy and coast live oak, and black oak are the pri- years (Minnich 1995; Zedler 1995; Conard mary tree species on lower mountain slopes and Weise 1998). Across most of the land- between 3,000 and 5,500 feet elevation in scape, current fire-return patterns in chaparral central and southern portions of the assess- appear to be either within or near this fifty to ment area (table 2.10). In the northern ranges, seventy year interval. Only in fire-prone areas lower montane forests can extend down to adjacent to the urban interface are burns oc- 1,000 feet elevation and contain California curring more frequently. bay, Pacific madrone, gray pine, and knobcone Another widely debated issue is whether pine (Griffin and Critchfield 1976). Often the average size and intensity of chaparral fires described as mixed evergreen forests (Munz have increased as a result of fire suppression. and Keck 1973), they are typically found in Some evidence suggests it has (Minnich 1989, small, scattered patches (roughly 50 to 800 1995), while other evidence suggests that large acres in size) surrounded by large expanses of conflagrations have always dominated chap- chaparral (fig 2.15). Thus, they are highly in- arral fire regimes (Byrne et al. 1977; Moritz fluenced by chaparral fire regimes. 1997). This subject is addressed in detail in Bigcone Douglas-fir and Coulter pine are the chapter 3 section on fire. Whether they essentially endemic to the coastal mountains represent a change from historic conditions of central and southern California (Coulter pine extends a ways into Baja California, Figure 2.14. Northern mixed chaparral along the Mexico) (Minnich 1987; Griffin and upper San Diego River, Cleveland National Forest. Critchfield 1976). These conifer species are Chaparral is much denser than coastal scrub and rarely found together, but both are frequently the shrubs have hard, woody stems. ANNE FEGE associated with canyon live oak. Both are highly influenced by chaparral fire regimes, but their life history strategies for responding to fire are very different. Bigcone Douglas-fir/canyon live oak for- ests frequently occur near streams in moist, shaded canyons and draws, where aspects are mostly north and east. At the upper end of their elevation range these forests appear on other aspects and become less restricted to canyons (McDonald and Littrell 1976). They

29 Table 2.10. Acres of lower montane forest types by mountain range. Values in parentheses are the percentage of those acres occurring on public lands. These figures represent land area where the specified vegetation type is dominant. They are derived from a large-scale GIS vegetation layer that combines data from several different mapping efforts (see “Infromation Sources” section, chapter 1).

Acres of Lower Cleveland NFSan Bernardino NF Angeles NF Los Padres NF Montane Forest San Santa San San San Castaic S. Los S. Santa N. Santa Types Diego Ana Jacinto Bernar- Gabriel Ranges Padres Lucia Lucia Ranges Mts Mts dino Mts Mts Ranges Rng Rng TOTAL

Bigcone Douglas-fir/ 8,339 2,650 1.115 12,931 46,882 1,872 14,274 88,063 canyon live oak (59%) (95%) (95%) (85%) (98%) (97%) (98%) (92%)

Coulter pine/ 12,084 68 12,416 562 19,459 1,446 37,200 83,235 canyon live oak (23%) (100%) (81%) (100%) (91%) (100%) (86%) (77%)

Canyon live oak woodland 12 2,940 2,425 14,346 38,728 15,395 45,669 119,515 (45%) (80%) (77%) (95%) (91%) (92%) (91%)

Foothill and knobcone 710 170 12,961 10,690 24,624 pine woodland (63%) (73%) (18%) (20%) (21%)

California bay forest 197 23,072 23,269 (76%) (77%) (77%)

Broadleaved upland forest 7,532 91 161 45 1,596 5,332 22,117 36,874 (1%) (2%) (7%) (5%)

TOTAL 27,967 5,749 16,117 27,415 86,172 17,977 81,365 19,739 93,079 375,580 (28%) (95%) (81%) (81%) (97%) (90%) (91%) (19%) (57%) (74%)

are evidently not well adapted to withstanding that limits understory fuel accumulation. fires and persist primarily by clinging to steep, These stands typically have few understory fire-resistant terrain (Minnich 1988; shrubs or flammable ground cover. McDonald 1990). Their ability to escape fires Bigcone Douglas-fir forests are believed to sweeping through the surrounding chaparral be negatively affected by changing fire patterns is due to their occurrence on precipitous slopes (Minnich 1988). Although there has not been and the formation of a dense, arboreal canopy a rangewide quantitative evaluation of habi- tat losses, it is widely believed that bigcone Figure 2.15. Scattered patches of Coulter pine Douglas-fir has declined significantly over the surrounded by chaparral in American Canyon, Los last ninety years as a result of crown fires and Padres National Forest. MARK BORCHERT poor post-fire recovery. Minnich (1999) has documented an 18 percent decline in the ex- tent of bigcone Douglas-fir in the San Bernardino Mountains since 1938. The increase in crown fires is attributed to higher fire intensities in the surrounding chap- arral, although there is little data to substantiate this possibility (see discussion in chapter 3 sec- tion on “Fire”). The most vulnerable stands are those on gentler slopes: Minnich (1980) observed 37 percent survival of bigcone Douglas-fir fol- lowing wildfires on slopes less than 20 degrees, 30 Chapter 2 but more than 90 percent survival on slopes land NF, pers. comm.). Re-establishment has greater than 40 degrees. been poor in some areas, due to brush cover. Coulter pine persists in a chaparral-domi- Coulter pines need openings for successful re- nated environment by being adapted for rapid generation. When overstory trees die without regeneration after fires. It has adapted to peri- an accompanying fire to clear a seed bed, seed- odic crown fires by having a relatively short ling establishment can be impaired. life span (fifty to one hundred years) and semi- serotinous cones that favor its re-establishment after fire (Vale 1979; Borchert 1985). As a re- Montane and Subalpine Conifer sult it appears to be more resilient to today’s Forests fire regime than bigcone Douglas-fir. Montane conifer forests consist of vary- The biggest threat to Coulter pine is mul- ing combinations of ponderosa pine, Jeffrey tiple fires in short succession (e.g., less than pine, white fir, black oak, canyon live oak, twenty-five years), that kill overstory trees be- sugar pine, incense-cedar, and western juni- fore an adequate seed crop has developed. In per (table 2.11). These forests are the such cases stands can fail to regenerate and dominant land cover type between the eleva- convert to chaparral. Extreme insect or dis- tions of 5,000 and 8,500 feet in the southern ease outbreaks can also threaten Coulter pine. California mountains and above 3,000 feet During the height of the drought in the late along the Monterey coast. Subalpine conifer 1980s, a major bark beetle epidemic killed ap- forests occur above 8,000 feet and consist of proximately 70 percent of overstory Coulter lodgepole pine, limber pine, white fir, and pines on Palomar Mountain (T.White, Cleve- western juniper (fig. 2.16).

Table 2.11. Acres of montane and subalpine conifer forest types by mountain range. Values in parentheses are the percentage of those acres occurring on public land. These figures represent land area where the specified vegetation type is dominant. They are derived from a large-scale GIS vegetation layer that combines data from several different mapping efforts (see “Information Sources” section, chapter 1).

Cleveland NFSan Bernardino NF Angeles NF Los Padres NF Acres of Montane Conifer San Santa San San San Castaic S. Los S. Santa N. Santa Diego Ana Jacinto Bernar- Gabriel Ranges Padres Lucia Lucia Forest Types Ranges Mts Mts dino Mts Mts Ranges Rng Rng TOTAL

Mixed coniferÐpine 40,082 98,062 20,494 852 159,490 (78%) (76%) (99%) (99%) (80%)

Mixed coniferÐfir35,383 26,590 53,889 37,001 152,863 (26%) (85%) (96%) (95%) (78%)

Jeffrey/ponderosa pine 15,485 2,351 58,526 5,515 43,507 16,210 141,604 (75%) (43%) (81%) (96%) (96%) (68%) (84%)

Black oak 8,580 3,771 4,550 369 1,248 1,538 1,014 21,070 (46%) (88%) (70%) (96%) (89%) (1%) (78%) (60%)

Redwood/Santa Lucia fir 16,658 16,658 (69%) (69%)

Subalpine conifer 2,090 5,916 10 234 8,250 (100%) (100%) (100%) (100%) (100%)

TOTAL 59,448 0 48,304 193,644 80,277 2,100 80,742 1,538 33,882 499,935 (42%) (78%) (79%) (97%) (93%) (96%) (1%) (69%) (79%)

31 tion changes at plot locations established dur- ing the Vegetation Type Map (VTM) Survey (Weislander 1935). Approximately 18,000 VTM plots were initially surveyed from 1929 to 1934 as part of a project to map the vegeta- tion of California (Minnich et al. 1995). They provide a valuable record of what the vegeta- tion structure and composition was over sixty years ago. Minnich et al. (1995) revisited sixty-eight VTM plots located in montane conifer forests Figure 2.16. Continuous stands of mixed conifer in the San Bernardino Mountains. Using dif- forest give way to alpine habitats on Mount San ferent methods, Savage (1994) studied this Gorgonio, San Bernardino National Forest. JOHN same issue in the San Jacinto Mountains. To STEPHENSON obtain data from additional mountain ranges, Some montane conifer stands have we revisited thirty-two VTM plots in the changed dramatically since the early 1900s, Mount Pinos/Mount Abel area, the San largely due to long-term fire exclusion Gabriel Mountains, and the mountains of San (Minnich et al. 1995). Fire suppression has Diego County. been extremely effective in upper mountain The results from each area were very simi- forests. Low- to moderate-intensity understory lar: Mid-elevation mixed conifer forests have fires, which were historically frequent occur- experienced (1) substantial increases in the rences in these forests (i.e., every fifteen to number of small diameter trees (fig. 2.18), (2) thirty years) (McBride and Lavin 1976), have reductions in the number of large trees, and been virtually eliminated over the last sixty to (3) shifts in species composition towards more eighty years. Resulting problems include (1) a white fir and incense-cedar and fewer Jeffrey/ large increase in the number of understory ponderosa pine and black oak. In contrast, trees (particularly shade-tolerant white fir and plots in Jeffrey pine forests on the more arid, incense-cedar); (2) increased risk of stand-re- desert side of the mountains showed little placing crown fires due to fuel buildup; and change. (3) increased mortality and reduced recruit- Subalpine forests in southern California ment of large trees (due to increased occur only in the highest ranges: the San understory competition). Jacinto, San Bernardino, and San Gabriel These problems are occurring primarily in mountains and small patches on the summit mesic forests where understory trees develop of Mount Pinos and Mount Abel. Most of rapidly. Stand densities in arid, desert-side for- these areas are within designated wilderness ests do not appear to be experiencing areas, including the largest stands on the slopes significant change. To estimate the spatial ex- of Mount San Gorgonio. In general, these tent of the problem, we developed a GIS-based small subalpine/alpine ecosystems are intact, model to predictively map areas likely to be stable, and little disturbed (with the exception experiencing overcrowded forest conditions of some heavy recreation use in the vicinity of and associated crown fire risk. Spatial data on mountaintop trails). Trees grow very slowly in vegetation type, canopy cover, annual precipi- these upper elevation forests and stands tend tation, elevation, and slope were used to to be open. predict potential problem areas (table 2.12) Fires are naturally infrequent in subalpine (fig. 2.17). forests and thus return intervals have not been To validate these predictions we examined significantly altered by suppression activities. existing and newly collected data on vegeta- When they do burn, it is usually in a stand- replacing crown fire during severe weather 32 Chapter 2

Table 2.12. Description of the model conditions used to predict areas of montane conifer forest with overcrowded stand conditions. The map of predicted areas is shown in figure 2.17.

Areas predicted to be experiencing high stand densification meet all of the following conditions: 1. Vegetation type is a conifer forest (but not bigcone Douglas-fir or pinyon/juniper) 2. Elevation is at or below 7,500 feet 3. Average annual precipitation is greater than 65 centimeters (25.6 inches) 4. Canopy cover is greater than 60 percent 5. Slope is less than 60 percent conditions (Minnich 1988). Several crown Desert Montane Communities fires have occurred in recent decades in subal- Arid slopes on the desert side of the moun- pine forests in the San Gabriel Mountains. tains are occupied by sparse pinyon-juniper While the result of human-caused ignitions, woodlands, semi-desert chaparral, sagebrush, it is unclear if these fires were abnormally se- and desert scrub (table 2.13). Single-leaf pin- vere or frequent. The extremely steep terrain yon pine generally dominates the higher in the San Gabriels may make these forests elevation slopes, while California juniper is more vulnerable as human-caused fire igni- prevalent at lower elevations, often on gentle tions increase. slopes or alluvium. Parry or four-needle pin- yon pine occurs in the San Jacinto Mountain region’s desert transition zone near Thomas Mountain.

Figure 2.18. A look at how stem densities by size class have changed in mixed conifer stands over the last sixty years. The left graph comes from VTM plots done in the early 1930s and the right graph comes from those same locations in 1997 (n = 7). Each bar represents +/- one standard deviation from the mean; the mean is indicated by the horizontal line through each bar. Pronounced increases in stem densities have occurred in the small diameter size classes, while the number of large diameter (>90 cm) trees has slightly declined. These results are from the mountains of San Diego County, but the same trend is seen in plot data from the San Bernardino Mountains (Minnich et al. 1995), the San Gabriel Mountains and Mount Pinos.

1930s 1997 600 600 Grand Total Grand Total 500 500

400 400

300 300

200 200 Stems per hectare Stems per hectare

100 100

0 0 <90 <90 10-29 30-59 60-89 10-29 30-59 60-89 Diameter at breast height (cm) Diameter at breast height (cm)

33 Pinyon-juniper woodlands are generally Bernardino Mountains (Fenn 1991a; Merrill open-canopy stands with sparse understory et al. 1992). vegetation. It is not a vegetation structure that Semi-desert chaparral is more open than carries fire well and pinyon pine is not adapted chaparral found on coastal slopes and has a to frequent fire. Fire-return intervals of sev- different mix of species. Flannel bush, bitter- eral hundred years are considered typical in brush, Tucker or Miller scrub oak, birchleaf these woodlands (Minnich 1988). mountain mahogany, and cupleaf ceanothus There have recently been several large fires are characteristic components of semi-desert in pinyon stands in the San Bernardino Moun- chaparral (Sawyer and Keeler-Wolf 1995). tains. One area even reburned several years Basin sagebrush is common in dry alluvial after a crown fire (S. Loe, San Bernardino NF, fans, meadows, and washes. Basin sagebrush pers. comm.), which is very unusual in such is particularly prevalent in the low elevations sparsely vegetated habitat. This has raised con- surrounding Mount Pinos and in the Garner cern about whether the spread of introduced Valley region south of Mount San Jacinto. grasses (primarily cheatgrass) is providing the There is no evidence that fire regimes in these fuels needed for fire to carry more effectively vegetation types are outside the range of natu- and frequently in these stands. If this is oc- ral variability. curring, it would only be in years of high Common land uses in desert-side habitats precipitation when there is sufficient moisture are mining, off-highway vehicle (OHV) rec- for the grass to become widespread. It is un- reation, and target shooting. Large limestone clear if this is actually happening, but the issue deposits in the northeastern portion of the San warrants further study because pinyon-juni- Bernardino Mountains have resulted in the per woodlands are extremely slow to recover development of several major open-pit mines. from fire and would be negatively affected by Exploratory drilling for oil and gas deposits is shortened fire-return intervals. Black stain root a major activity in the southern Los Padres. disease is also a significant problem for pin- These activities have caused habitat losses and yon pine, particularly in portions of the San are affecting sensitive resources in some

Table 2.13. Acres of desert-side montane vegetation types by mountain range. Values in parentheses are the percentage of those acres occurring on public lands. These figures represent land area where the specified vegetation type is dominant. They are derived from a large-scale GIS vegetation layer that combines data from several different mapping efforts (see “Information Sources section, chapter 1).

Cleveland NFSan Bernardino NF Angeles NF Los Padres NF Acres of Desert- side Montane San Santa San San San Castaic S. Los S. Santa N. Santa Diego Ana Jacinto Bernar- Gabriel Ranges Padres Lucia Lucia Vegetation Types Ranges Mts Mts dino Mts Mts Ranges Rng Rng TOTAL

Pinyon woodland 444 13,225 57,776 26,065 17,029 236,780 351,337 (91%) (83%) (89%) (79%) (12%) (86%) (82%)

Semi-desert chaparral 27,114 37,354 50,021 48,569 5,332 78,632 160 247,182 and Tucker scrub oak (83%) (67%) (83%) (70%) (20%) (86%) (57%) (78%)

Basin sagebrush 6,861 15,416 8,282 2,856 1,678 15,373 50,466 (25%) (30%) (76%) (37%) (54%) (43%)

Desert scrub 4,968 26,170 4,466 54 35,658 (100%) (52%) (47%) (58%)

TOTAL39,387 0 92,165 120,545 77,544 24,039 330,785 160 0 684, 643 (75%) (59%) (84%) (72%) (13%) (85%) (57%) (77%)

34 Chapter 2 locations, but from a broad ecosystem perspec- ented. The Big Sur coastline receives most of tive they are relatively localized. the recreation activity. Target shooters and OHV enthusiasts tend to concentrate in desert-side habitats because Aquatic and Riparian the sparsely vegetated terrain is conducive to Communities these activities. Uncontrolled target shooting Freshwater aquatic habitats are uncom- has raised safety and pollution (particularly mon in coastal southern California and most from lead accumulation) concerns and several have been substantially modifed by altered of the national forests are currently reviewing stream flow regimes. Essentially all the large their policies on this activity. rivers are to some extent dammed or diverted (figs. 2.19–20), thereby significantly altering Monterey Coast Communities the extent and character of riverine habitats The northern Santa Lucia Range along (see section on “The Influence of Water Regu- the Monterey coast receives substantially lation and Withdrawal” in chapter 3). higher amounts of precipitation than the rest Deep-water reservoirs formed by dams are a of the assessment area and thus contain plant new and entirely different type of aquatic habi- communities that are more similar to those tat that didn’t exist historically in the region. found in northern California. Along the im- The aquatic fauna found in these reservoirs mediate coast, narrow stands of redwood trees tends to be dominated by non-native species. occur in deep canyons surrounded by coastal Given the dominant role that impound- scrub, chaparral, and grassland. ments have in determining a drainage’s habitat On the inland side of the mountain crest, potential, we partitioned streams into analy- stands of ponderosa pine, the endemic Santa sis watersheds based on whether they occurred Lucia fir, and true Douglas-fir (a different above or below major impoundments. A da- species than bigcone Douglas-fir) occur at the tabase was developed that provides baseline highest elevations. Below the conifer belt on information on each analysis watershed and the the inland side of the mountains is a mosaic major streams occurring within them. Informa- of chaparral, mixed evergreen forest, and oak tion compiled for each stream includes linear woodland. California bay, Pacific madrone, miles by elevation intervals, percent on public and live oak are common components of the land, occurrence of roads along the stream cor- evergreen forest. This is the only place in the ridor, land use intensity, degree of stream flow assessment area where Douglas-fir and mad- alteration, and level of non-native species infes- rone are common trees. tation. Information on each watershed includes Although fires are generally smaller and the percent of the entire watershed that is on less frequent in this mesic area, a single event public land, road densities in the watershed, and (the approximately 180,000-acre Marble occurrences of both species of concern and in- Cone fire) burned much of the region in the vasive non-native species. A complete table of late 1970s (Griffin 1982; Moritz 1997). It is the data compiled for each watershed and stream unclear if this is a typical historic pattern, but is provided in appendix C. there is little evidence to suggest that the area is experiencing vegetation changes as a result Streams and Rivers of shifting fire regimes. Most streams in southern California have Rugged terrain in the area historically lim- very low flow during the summer months and ited road development and led to the in many cases dry up in the lower and upper- establishment of the Ventana Wilderness, most portions. However, streams that flow which encompasses the majority of the north- through rock canyons often have perennial ern Santa Lucia Range. Land use in this region flow because deep pools are fed by ground- is relatively limited and strongly recreation ori- water recharge. This pattern of low flow in

35 summer, which reflects the Mediterranean cli- The middle and lower portions of these mate, results in an interesting situation in streams, typically found at elevations below which the headward parts of streams may be 3,000 feet, support a higher number of aquatic dry, the middle portion wet, and the low por- and riparian species. Perhaps because habitat tion dry during the summer months (Faber et loss has been so extensive there, low-elevation al. 1989). streams also have a much higher number of

Figure 2.19. The primary rivers and streams in the southern portion of the assessment area with the underlying public lands. Shown in red are locations of dams (circles) and major diversions (triangles). Baldwin Lake, the only large natural lake in the region, can be seen in the upper right, just west of Arraste Creek.

36 Chapter 2

Figure 2.20. The primary rivers and streams in the northern portion of the assessment area with the underlying public lands. Shown in red are locations of dams (circles) and major diversions (triangles). associated threatened, endangered, and sensi- cent below 1,000 feet (fig 2.21). The low- tive (TES) animal species (table 2.14). elevation rivers also face greater threats. Landownership patterns and threat fac- Water flows are much more likely to be di- tors also differ dramatically by elevation. verted or altered, the adjacent terraces are Seventy-four percent of stream miles above commonly farmed or developed, and there is 3,000 feet elevation are on public lands, but a greater abundance of invasive non-native this proportion drops to 50 percent between species. 1,000 and 3,000 feet, and down to 17 per- 37 Given the significance and rarity of hy- 2500 drologically intact low-elevation streams, those on private land on public land occurring on public lands should be given 2000 special attention. Of particular import are the sections of these streams that are in a relatively 1500 unmodified state. These are the areas where 50% 74% 1000 historic disturbance regimes and the natural miles of stream range of variability may still be possible to 500 maintain. To identify these areas we used GIS 17% data to select the low-elevation streams best 0 Streams Streams Streams represented on public lands and the sections below 1,000 to above of them that do not contain upstream dams 1,000 ft 3,000 ft 3,000 ft or diversions. Then we considered informa- tion on land use intensity, invasive species, and Figure 2.21. Bars show the miles of all streams landownership patterns in the upstream wa- along the central and southern California coast by elevation group. The shaded portion is the tershed (table 2.15). proportion that occurs on public land, with the The streams listed in table 2.15 are not percent value shown above it. The occurrence of necessarily the most important ones in terms streams on public lands increases dramatically with of TES species populations. However, the hy- elevation. drologically unregulated sections of these streams are likely to be the best remaining ex- amples of intact low-elevation aquatic non-native species. Invasive aquatic animals ecosystems in the central and southern Cali- that are causing problems in many streams fornia coastal region. Thus, they represent our include green sunfish, bluegill, bullfrogs, cray- best opportunities for maintaining intact fish, mosquitofish, brown trout, bass, aquatic ecosystems. bullheads, red-eared sliders, and African Next to alteration of stream flow, the big- clawed frogs. The invasive plants arundo and gest factor threatening the health of native tamarisk are also spreading, displacing native aquatic ecosystems is the spread of invasive vegetation and causing a decline in surface

Table 2.14. Threatened, endangered, and sensitive (TES) aquatic and semi-aquatic animal species that are associated with either low- or high-elevation streams.

Aquatic TES animals found primarily in Aquatic TES animals found primarily in low-elevation streams (<3,000 ft) high-elevation streams (>3,000 ft)

California red-legged frog Mountain yellow-legged frog Foothill yellow-legged frog Shay Creek stickleback Coast range newt Southwestern arroyo toad Santa Ana sucker Santa Ana speckled dace Arroyo chub Southern steelhead Unarmored threespine stickleback California red-sided garter snake Southwestern pond turtle

38 Chapter 2

Table 2.15. The most significant low-elevation (below 3,000 feet) streams from the standpoint of linear miles on public lands. Those in bold are identified as having relatively high potential for maintaining aquatic ecological integrity, due to a high amount of unregulated streamflow (i.e., not dammed or diverted).

Stream Miles below 3,000ft

Stream Mountain Range On Flow % Public Land Use Invasive Subarea Public Undiverted Land in Intensity Species Land on Public Watershed Infestation (Total mi) Land

San Antonio River* No. Santa Lucia 56.0 47.7 64% Mod ? Nacimiento River* No. Santa Lucia 34.6 25.1 48% Mod ? Piru Creek So. Los Padres 26.6 7.3 80% High High Sisquoc River So. Los Padres 26.4 26.4 87% Low Low Santa Ynez River So. Los Padres 26.1 0 High High

Big Sur River (S & N fks) No. Santa Lucia 25.7 25.7 93% Low Low Sespe Creek So. Los Padres 23.9 23.9 91% Mod Mod San Mateo Creek Santa Ana Mts. 22.8 22.8 92% Low Mod Santa Margarita River** San Diego Ranges 21.4 21.1** 38% Mod High Santa Ana River San Bernardino Mts. 17.6 0 87% Mod High

San Gabriel River San Gabriel Mts. 17.6 12.5 95% High Mod Arroyo Seco No. Santa Lucia 16.5 16.5 60% Mod Mod West Fk, San Gabriel R. San Gabriel Mts. 15.7 6.0 100% Mod Mod Cuyama River So. Los Padres 14.8 4.5 70% Mod ? Manzana Creek So. Los Padres 14.3 14.3 100% Low Low

Carmel River No. Santa Lucia 14.0 5.0 49% Mod Low Elizabeth Lake Liebre Mtn. Area 13.4 13.4 84% High Mod Salinas River N&S Santa Lucia 13.1 2.2 22% High High San Diego River San Diego Ranges 13.0 7.9 42% Low/Mod Mod Mono Creek So. Los Padres 13.0 13.0 96% Low Low

San Juan Creek Santa Ana Mts. 12.2 12.2 52% High Mod Big Tujunga Creek San Gabriel Mts. 11.4 0 87% High High Pine Valley Creek San Diego Ranges 10.3 10.3 81% Low Mod Indian Creek So. Los Padres 9.5 9.5 100% Low Low Santa Cruz Creek So. Los Padres 9.4 9.4 58% Mod ?

* These streams are predominately on military lands. ** The flow on the Santa Margarita is partially diverted by a dam on Temecula Creek. water availability in some streams (Rieger and Lakes Kreager 1989). Collectively, these introduced Almost all lakes in the assessment area are species are causing a serious decline in the ca- man-made reservoirs formed by dams. How- pability of aquatic habitats to support native ever, a few small natural basins exist that hold species. water all or most of the time. The majority of these straddle the San Andreas Fault: Jackson 39 Lake, Elizabeth Lake, Lake Hughes, and Lost Riparian ecosystems are linear and often Lake. In addition, Crystal Lake in the San Gabriel narrow features on the landscape (fig. 2.22). Mountains, Dollar Lake in the San Bernardino For that reason, they are difficult to accurately Mountains, and Hidden Lake in the San Jacinto map across large areas using air photos or sat- Mountains are small natural lakes. ellite imagery. Our existing vegetation maps There is one large natural, ephemeral lake do not fully capture the distribution of ripar- in the mountains: Baldwin Lake in the east- ian habitats; thus, we have not attempted to ern San Bernardino Mountains. This large provide acreages for them. A detailed map of shallow basin fills with water during wet peri- riparian plant communities would be ex- ods. It can retain water year-round for several tremely useful for management purposes. years when conditions are right. When full, Related information on the extent of rivers and its shallow waters attract large numbers of wa- streams in the region is provided in the sec- terfowl and also provide habitat for the rare tion on aquatic ecosystems. Shay Creek stickleback fish. The watershed Riparian habitats have declined dramati- that feeds Baldwin Lake is also the primary cally at low elevations, where they historically water supply for the community of Big Bear were most extensive. It is estimated that City. This may be resulting in reduced flows channelization and diversion of streams in the into the lake. last century have reduced the extent of ripar- The large, man-made lakes are essentially ian habitats in southern California by over 90 distinct ecosystems, with an aquatic fauna that percent (Faber et al. 1989). More recently, bears little resemblance to what naturally oc- strong regulatory policies on “no net loss” of curs in the streams that formed them. Almost wetlands have helped to check this decline. all support fisheries and are stocked with vari- The extent of riparian habitats on public ous species of bass, trout, catfish, and sunfish. lands is relatively stable. So too is the struc- Fishing is a very popular recreational activity tural condition of these habitats. Livestock at many of these lakes, attracting far more an- grazing in riparian areas within the national glers than do the streams. The lakes have also forests has been substantially reduced, result- attracted species such as bald eagle and osprey ing in some dramatic improvements in that were formerly very rare in these moun- vegetation condition. Concentrated recreation tains. These lakes also facilitate the use is causing localized habitat damage in some introduction of a wide variety of invasive non- areas. Foothill riparian areas are cool, pleas- native species into the surrounding streams ant places in the vicinity of large urban (see “Invasive Species” section, chapter 3). populations so recreation pressure is inevitable.

Low-Elevation Riparian Habitats Figure 2.22. Linear riparian woodlands like this one in San Francisquito Canyon, Angeles National Forest, Riparian habitats reach their peak as dis- contrast sharply with the surrounding arid tinct ecological communities along mid- to shrublands. SHAWNA BAUTISTA large-order streams below 4,000 feet in the foothills and valleys. There are many differ- ent riparian plant associations (table 2.7), but foothill riparian woodlands generally fall into one of three broad categories: (1) Fremont cot- tonwood/willow, (2) California sycamore/ coast live oak and (3) white alder (Borchert unpubl. manuscript). They are extremely pro- ductive and important habitats for wildlife (see Faber et al. 1989 for an excellent overview of southern California riparian habitats). 40 Chapter 2 However, habitat degradation tends to be lo- Rare Communities calized in a few popular, easily accessible areas. A more insidious and widespread prob- Twelve rare ecological communities were lem is the spread of invasive, non-native identified in the assessment area. Communities species. The brown-headed cowbird, which fall into this category if there is some concern parasitizes the nests of native birds, and Eu- over their ability to persist in the region. Four ropean starlings, which displace native are defined by unusual soils and eight are plant cavity-nesting birds, are causing declines in communities either narrowly distributed within habitat capability in many areas. Bullfrogs, the assessment area or threatened in a portion of African clawed frogs, and green sunfish are their natural range. Acreage estimates for the spreading in many drainages, causing large twelve communities are summarized in table impacts on native amphibians, aquatic rep- 2.16 and brief descriptions follow. tiles, and fish. Arundo (giant cane) and tamarisk are invasive plants that are Valley Oak Woodlands outcompeting native riparian vegetation in Valley oak (Quercus lobata) is endemic to some areas. Arundo in particular is spreading California, occurring in areas with relatively rapidly in low-elevation riparian areas. mild winters west of the Sierra Nevada Moun- tains (Axelrod 1977). The species forms extensive woodlands, some of which occur in the northern half of our assessment area.

Table 2.16. The extent and distribution of rare community types on public lands. Acreages are derived from GIS coverages of vegetation, species, and soils distributions.

Total Mapped Percent within Percent on Public Rare Communities Acres in Central Assessment Lands within and South Coast Area Assessment Area Bioregions1 (acres)

Valley oak woodlands unknown <20% 8% (680) Engelmann oak woodlands 53,8102 82% 12% (6,461)3 Black walnut woodlands 23,5694 17% 12% (2,828) Cuyamaca cypress groves 230 100% 100% Tecate cypress groves 6,758 15% 85% (5,744) Gabbro outcrops 81,680 55% 41% (33,489) Montane meadows 55,446 100% 38% (21,070) Pebble plains 379 100% 60% (227) Limestone/carbonate 20,893 90% 87% (18,177) outcrops Serpentine outcrops unknown (31,470) Sargent cypress groves 1,585 100% 74% (1,173) Santa Lucia fir forests 7,576 100% 95% (7,197)

1 based on bioregions as defined by the California Bioregional Council 2 calculated using top four cover classes (3, 4, 5, and 6) from Scott (1990) 3 includes private reserves (e.g., portions of the Santa Rosa Plateau) 4 from mapped polygons by Weislander (1935)

41 Valley oaks are most prevalent at low eleva- tions in the Santa Lucia Ranges but also extend into portions of the southern Los Padres and Castaic regions, and the northern flank of the San Gabriel Mountains (Hickman 1993; Grif- fin and Critchfield 1972). The southernmost occurrences of valley oak woodland are found in Los Angeles County in the San Fernando and Santa Clarita valleys and the Santa Monica Mountains (Pavlik et al. 1991). True to its name, this tree typically occu- pies valley floor and lower foothill Figure 2.23. Valley oak woodland at Wagon Caves communities where there are deep soils (fig. Candidate Research Natural Area, Los Padres National 2.23). Its distribution also appears to be asso- Forest. MARK BORCHERT ciated with shallow water tables (Griffin 1977). Valley oaks do extend up the mountain slopes the importance of valley oak conservation on in places. They occur at 5,000 feet on Chews public lands. Ridge in the northern Santa Lucia Range and Tree regeneration is also considered a prob- extend up to 5,600 feet in the Tehachapi lem in valley oak woodlands. Many stands are Mountains. reported to be especially devoid of trees estab- Valley oak frequently forms open wood- lished in the last 75 to 125 years (Pavlik et al. lands with a grass-dominated understory. 1991). Factors cited as contributing to this lack These oak savannas are often the dominant of regeneration include consumption of acorns plant community in broad valleys that sur- and seedlings by livestock, tilling of cropland round the mountains of Santa Barbara, San around mature trees, lowering of the water Luis Obispo, and Monterey counties. Along table through groundwater pumping, and drainages the species forms denser riparian competition from non-native grasses and other forests (Holland 1986) and is often found exotic species (C. Blair, CNPS, in litt. 1998). with blue oak, black oak, coast live oak, sy- The presence of non-native annual grasses in camore, and black walnut (Sawyer and native grasslands has been shown to increase Keeler-Wolf 1995). oak seedling mortality by limiting the avail- Valley oak woodlands are poorly repre- ability of soil moisture (Danielsen and sented on public lands, although a more Halvorson 1991). Non-native annual grasses detailed mapping effort is needed to better grow and utilize soil moisture faster than na- quantify the exact amount. On private lands, tive perennial grasses. Oak seedlings exposed the rapid expansion of agriculture and urban to rapid declines in soil moisture experience development along the central coast is caus- water stress and display reduced growth. In ing a serious reduction in the extent of these controlled experiments, Danielsen and woodlands (R. Cowan, The Quercus Group, Halvorson (1991) found that valley oak seed- in litt. 1998). For example, the clearing of lings were significantly larger when growing oak savannas for large vineyard operations is in association with native purple needlegrass occurring in the foothills and valleys of Santa (Stipa pulchra) than when grown with wild oats Barbara County. More than 2,500 oaks in the (Avena fatua). Santa Ynez and Los Alamos valleys have been felled during the last two years and county Engelmann Oak Woodland officials predict vineyard acreage to triple Engelmann oak (Quercus engelmannii) within ten years (Cannon 1998). These areas woodlands are distributed from the San are outside the assessment area but illustrate Gabriel Mountains south to Baja California, Mexico; however, most occur in the foothills 42 Chapter 2 of San Diego and southwestern Riverside and Keeler-Wolf 1995). They commonly form counties (fig. 2.24). Populations also occur on open savannas (less than 10 percent canopy Santa Catalina Island. The greatest concen- closure) and woodlands (greater than 10 per- tration of these woodlands is found in the cent canopy closure) with grassland foothills of San Diego County between understories (R. Cowan, The Quercus Group, Palomar Mountain and Cuyamaca Peak. An- in litt. 1998)(fig. 2.25). In riparian areas the other major occurrence is located on the Santa species can occur in dense stands with other Rosa Plateau on the southeastern flank of the hardwoods (Holland 1986). Santa Ana Mountains. The species is the only Some of the most successful stands of representative of subtropical white oaks in Engelmann oak grow on clay soils formed California and represents the northwestern from a gabbro or basalt substrate (St. John extent of their range (Scott 1990). 1992). In San Diego County the species is Engelmann oaks are found at elevations sometimes found on rocky, north-facing slopes ranging from 160 to 4,500 feet on valley floors, with an understory of coastal sage scrub or foothill slopes, and raised stream terraces chaparral. In these instances it often hybrid- within riparian corridors (Scott 1989; Sawyer izes with scrub oak or Muller’s oak.

Figure 2.24. The distribution of Engelmann oak and black walnut in southern California.

43 to pursue acquisition of lands containing En- gelmann oak when they come up for sale. In recent years, major progress has been made in conserving this species through the purchase of key areas by Riverside County (on the Santa Rosa Plateau), San Diego County (on Volcan Mountain), CalTrans, and the Cleveland Na- tional Forest (Roberts and Rutherford ranches). The primary management concern for Engelmann oak woodlands on public lands is Figure 2.25. A mix of Engelmann and coast live maintaining sufficient regeneration. The long- oak form a relatively open woodland on the term viability of Engelmann oak appears to Rutherford Ranch, Cleveland National Forest. STAN CALHOUN be hampered by sporadic regeneration com- bined with unnatural rates of disturbance. Acreage estimates for this woodland type Livestock grazing and competition for soil vary depending on whether Engelmann oak moisture from introduced annual grasses both is mapped everywhere it occurs or just where appear to cause low recruitment rates for the it is the dominant tree. Based on our GIS veg- species and there is a noticeable absence of etation layer, Engelmann oak woodland is the young trees in many woodlands (Lathrop and dominant vegetation type over an estimated Osborne 1990; Pavlik et al. 1991). 21,083 acres—17,054 acres in San Diego County and 4,029 acres in the Santa Rosa Pla- Walnut Woodland teau region. In contrast, Tom Scott used aerial Black walnut (Juglans californica var. photographs and ground-truthing to map ap- californica) woodlands are an uncommon foot- proximately 78,000 acres that contain at least hill habitat that is distributed from Santa some Engelmann oak (it was subdominant to Barbara County south to northern San Diego coast live oak in over half of this area)(Scott County (fig. 2.24). The easternmost stands 1989). Rarely does the species occur in pure occur in southwestern San Bernardino County stands (over less than 1,300 acres based on in Day, Etiwanda, and San Sevaine canyons Scott’s map). Seventy-eight percent of the En- at the foot of the San Gabriel Mountains. gelmann oak mapped by Scott occurs within Large stands also occur in Ventura, Los Ange- the assessment area, with the remaining acres les, and northern Orange counties (Quinn located to the west in more coastal areas of 1989; Keeley 1990). Woodlands are scattered San Diego County. in low foothills surrounding the Santa Clara Engelmann oak woodlands are declining River drainage (including the Santa Susana primarily due to habitat loss on private lands. and Sulphur mountains), in the Santa Ynez Eighty-eight percent of Engelmann oak habi- Mountains, along the north side of the Santa tat in the assessment area is located on private Monica Mountains, along the base of the San land (Scott 1989). The tree inhabits the small- Gabriel Mountains, and in the Simi, San Jose, est natural range of any oak species in Puente, and Chino hills. Other stands occur California and is located next to the fastest within the lower foothills of the southern Los growing urban landscape in the country (Scott Padres and Castaic regions. 1990). Encouraging private landholders to Black walnut can be the dominant tree in protect this species on their properties is key the canopy or occur in mixed stands with other to conserving Engelmann oak (T. Scott, UC hardwoods such as coast live oak (fig. 2.26). Riverside, in litt. 1998). In addition, it is im- At Los Pinetos Spring in the western San portant for public land management agencies Gabriel Mountains, walnut grows with bigcone Douglas-fir and canyon live oak 44 Chapter 2 (S. Boyd, Rancho Santa Ana Botanic Garden, or disease, and it may prove to be a combina- pers. comm.). Some isolated stands occur tion of factors. Intensive livestock grazing in within chaparral and coastal sage scrub (Esser walnut woodlands has been shown under cer- 1993). Walnut usually occupies mesic areas tain conditions to lower the survival rates of (i.e., riparian corridors, floodplains, and walnut seedlings by direct herbivory and by north-facing slopes) and prefers soils with a the introduction of non-native taxa into the high clay content. understory (Esser 1993). Conversion from a Walnut woodlands are considered a de- native perennial grass understory to one domi- clining plant community due to habitat loss nated by non-native annual grasses is believed on private lands and low representation on to be a primary cause of low regeneration in public lands. Small populations are located on walnut woodlands much the same way it has the Angeles, San Bernardino, and Los Padres affected oak woodlands (L. Merrill, San Ber- national forests but quantitative data is avail- nardino NF, in litt.). A walnut woodland at able only for the Los Padres National Forest. Hopper Mountain on the Los Padres National This data is based on Weislander maps devel- Forest contains a large amount of Avena but oped in the 1930s and probably represent very little if any walnut seedlings. rough acreage estimates (Weislander 1935). A The effects of existing fire regimes on wal- better determination of the current distribu- nut are poorly understood. The variety is tion of this community is needed. Of the top-killed by most fires but reproduces veg- 23,569 acres mapped in southern California, etatively from the root crown and trunk after only 12 percent are located on public lands. burning (Esser 1993). The great majority of walnut woodlands are found in urban interface areas. Cuyamaca Cypress Groves Devegetation of private lands for development In the strict sense, Cuyamaca cypress appears to be the primary threat to this com- (Cupressus stephensonii) is known only from munity. The tree has high horticultural the Cuyamaca Mountains of San Diego potential, however, sometimes being incorpo- County and is the most narrowly distributed rated into urban forestry projects, and private cypress in California. Some taxonomists be- landowners are being encouraged to retain lieve, however, that the tree is really an Arizona these woodlands as part of their landscaping. cypress variant (C. arizonica ssp. arizonica). Lack of sufficient regeneration is another This variant also occurs in the southern Sierra problem observed in some walnut woodlands. Juarez east of Santa Catarina (R. Minnich, UC It is unclear whether the regeneration prob- Riverside, in litt. 1998). In this sense lem is caused by livestock grazing, invasion of Cuyamaca cypress may be part of a larger spe- non-native annual grasses, seedling predation, cies range that includes occurrences in Arizona, neighboring Sonora, and the Sierra Juarez. Figure 2.26. Southern California black walnut Cuyamaca cypress forms several groves in woodland at California State Polytechnic University, the Cuyamaca Peak/King Creek area in the Pomona. JANET NICKERMAN mountains of San Diego County (fig. 2.27). The groves represent a single population that occurs naturally over an estimated 230 acres on both the Cleveland National Forest and Cuyamaca Rancho State Park (Winter 1994). In 1991 the Cleveland National Forest estab- lished the King Creek Research Natural Area to protect the cypress and its habitat. An ap- parently introduced population occurs in the Agua Tibia Wilderness near Palomar Moun- tain. 45 The tree usually grows in gabbro-derived seed as well as to prepare the soil for enhance- clay soils, on steep slopes along drainages. It ment of germination. While periodic fires are can be dominant in the canopy or co-domi- therefore necessary for regeneration, short fire- nant with Coulter pine. Groves are typically return intervals (e.g., less than every forty years) surrounded by chaparral vegetation composed appear to gradually decrease stand densities by of chamise, manzanita, and scrub oak (fig. preventing trees from reaching maturity and 2.28). Two other rare plants, Dunn’s mariposa producing seed (Winter 1994). The species has lily (Calochortus dunnii) and Orcutt’s brodiaea relatively thin, exfoliating bark that provides (Brodiaea orcuttii), are found with Cuyamaca little protection from fire and is usually killed cypress. in wildfire events (Sullivan 1993b). Since trees Like all native cypress in California, typically reach maturity and begin to produce Cuyamaca is adapted to fire and produces se- viable seed at approximately forty years, a fire- rotinous or closed cones at maturity (Zedler free interval of greater than forty years is 1986). These cones require the intense heat needed to maintain the seed pool/bank. generated by fire to open and disperse their

Figure 2.27. The distribution of gabbro soils, Cuyamaca cypress, and Tecate cypress in southern California.

46 Chapter 2 R. Minnich, UC Riverside, in litt. 1998). Usually found on mesic east- or north-fac- ing slopes, Tecate cypress grows in alkaline, clay soils derived from ultramafic gabbroic rocks or metavolcanics (Zedler 1981)(fig. 2.29). The tree was once more widespread but is now restricted to these unusual soils where it lacks competition (Schoenherr 1992). Like Cuyamaca cypress, Tecate can be the defining component of southern interior cypress for- est—a dense, fire-maintained low forest that Figure 2.28. Cuyamaca cypress and chaparral at King forms even-aged stands surrounded by chap- Creek, Cleveland National Forest. These young trees arral (Esser 1994a). Ceanothus, scrub oak, and germinated after the 1970 Boulder Fire. MOZE MOSSAY chamise species are commonly found with Tecate cypress, and the trees may also be Cuyamaca cypress is an increasingly rare viewed as a phase of chaparral vegetation species within the assessment area. The Cleve- (Zedler 1981). land National Forest has developed a species Tecate cypress is strongly influenced by management guide that summarizes ap- fire; seeds remain in the cones until fire causes proaches to fire management and provides them to be dispersed and the trees themselves guidelines for the use of fire in enhancing cy- are killed. Environmental conditions present press stands on the forest (Winter 1994). after fire induce the seeds to germinate and re-establish the population. Despite this ad- Tecate Cypress Groves aptation to fire, the species is vulnerable to Tecate cypress (Cupressus forbesii) occurs either excessively short or long fire-return in- at elevations as low as 65 feet in Baja Califor- tervals (Zedler 1981). Under current nia, Mexico, and up to 4,200 feet in the San conditions, overly frequent fire is the much Diego and Santa Ana mountains (J. Gibson, greater threat. Tecate cypress trees begin to San Diego Natural History Museum, pers. produce cones after about ten years but take comm.). Its distribution is centered in Baja; about fifty years to reach maximum cone pro- however, some significant colonies are found duction (Zedler 1977). If they reburn at north of the border. A 50-acre grove on Guatay intervals less than fifty years, reduced amounts Mountain in San Diego County and a 960- of viable seed for regeneration would be ex- acre occurrence in the Sierra Peak/Coal pected. Canyon area of the northern Santa Ana Moun- Eighty-five percent of Tecate cypress tains are located in the assessment area (fig. within the United States is located on public 2.27). Groves in the Sierra Peak/Coal Can- lands yet the species is becoming increasingly yon area represent the northern limit of Tecate rare in these areas (K. Winter, Cleveland NF, cypress distribution and its only Orange unpubl. notes). Reduced stand densities are County locality (White 1990). The largest attributed mainly to increases in fire frequency. stand of Tecate cypress in California (over Data collected at both Tecate Peak and Otay 5,000 acres) is south of the assessment area at Mountain suggests that some of the groves Otay Mountain along the border with Mexico. there are diminishing in size. Using fire his- Most of that occurrence is situated on land tory records, ring counts, and aerial managed by the BLM. Numerous groves of photographs, Paul Zedler was able to deter- Tecate cypress occur on the Mexico side of mine the burn intervals at Tecate Peak from Otay and Tecate peaks and in the coastal approximately 1800 through 1975, and at mountains of Baja California, extending about Otay Mountain from 1943 to 1976 (Zedler 150 miles down the peninsula (Esser 1994a; 47 (Mitoura thornei) are found exclusively with Tecate cypress; however, the butterflies have only been observed in the grove on Otay Mountain, outside the assessment area (Murphy 1990).

Gabbro Outcrops Gabbroic rock exposures are found in the foothills and mountains of San Diego County Figure 2.29. Mature Tecate cypress on Otay and the Santa Ana Mountains (fig. 2.27). In Mountain, San Diego County. MILAN MITROVICH the San Diego region the substrate is known from Cuyamaca, Guatay, McGinty, Potrero, Viejas, Poser, Los Pinos, Corte Madera, and 1981). Sampling after the most recent (i.e., Iron mountains (Beauchamp 1986). An esti- 1975 and 1976) fires showed that stands at mated 81,680 acres of gabbro-derived soils least fifty-two years old at the time of a fire occur in southern California. Forty-one per- produced a greater number of seedlings per cent of those acres are found on public lands, pre-burn tree, and that these stands reestab- most within the Cleveland National Forest. lished at densities several times higher than Commonly called gabbro, the igneous pre-fire densities (Zedler 1981). Conversely, rock is highly erodable and weathers into a stands thirty-three years old or younger at the dark reddish, iron- and magnesium-rich soil time of a fire established fewer seedlings than (Schoenherr 1992)(fig. 2.30). The soil is some- there were mature trees before the fire and ex- times characterized as a poorly draining clay. perienced significant decreases in stand Soil series formed from gabbro include Las densities. Posas, Boomer, and Auld. They form ecologi- Mining activities have also adversely af- cal islands within more common substrates, fected Tecate cypress in the assessment area. such as granodiorite, and support unique plant Strip mining of underlying clay deposits de- communities including Cuyamaca and Tecate stroyed some groves on private lands in the cypress groves (Gordon and White 1994). Sierra Peak/Coal Canyon area of the Santa Ana Several herbaceous plants are also endemic to Mountains (Esser 1994a). gabbro-derived soils, including two federally A species management guide for Tecate listed species: San Diego thorn-mint cypress was developed by the Cleveland Na- (Acanthomintha ilicifolia) and Mexican tional Forest that summarizes approaches to flannelbush. fire management and provides guidelines for A potential threat to gabbro habitat on the use of fire in enhancing cypress stands on national forest system lands is the construc- the forest (Winter 1991a). The Guatay Moun- tion of communication sites on mountaintops. tain occurrence is proposed for designation as Impacts to the habitat in other areas are largely a Research Natural Area (RNA). An estimated unknown. Strip mining of gabbro-derived clay 64,000 trees occur at this site (Winter 1991a). deposits has occurred on private lands in the A large portion of the Coal Canyon popula- northern and eastern Santa Ana Mountains tion (540 acres) was recently purchased by the (Esser 1994a) and there is potential for in- CDFG and designated as an ecological reserve. creased mining to occur. Two federally listed plants, Braunton’s milk-vetch (Astragalus brauntonii) and Mexi- Montane Meadows can flannelbush (Fremontodendron Montane meadows are found throughout mexicanum), are found with Tecate cypress. the assessment area, typically at elevations Larvae of the rare Thorn’s hairstreak butterfly above 3,200 feet, and are represented on all 48 Chapter 2 Meadows tend to form where there are gentle gradients and relatively impervious bed- rock occurring in combination with appropriately sized upstream drainage basins. Where basins are large and produce high vol- umes of water, fine soil materials are washed away, preventing the establishment of meadow habitat. Stable meadows are those with shal- low slopes and smaller drainage basins where fine materials are allowed to accumulate. Meadows that occur narrowly along streams and creeks are referred to as “stringer mead- ows.” Meadows often form on or in close proximity to fault zones. The availability of subsurface waters may be locally increased by these subterranean impoundments (H. Gor- don, Remote Sensing Lab, in litt. 1998). A mix of hardwood and conifer species typically encompasses meadows at lower el- evations. At higher elevations the surrounding forest shifts to mixed conifer and fir species. Jeffrey pine, white fir, incense-cedar, and black oak are frequent components of surrounding vegetation in the mountains of San Diego County (Winter 1991b). Montane meadows Figure 2.30. Rocky gabbro soil and chaparral at are dominated floristically by sedges and King Creek, Cleveland National Forest. The soil is rushes, with perennial herbs and grasses also rich in iron and recognized by its reddish color. MOZE well represented. Four federally listed plants, MOSSAY San Bernardino blue grass (Poa atropurpurea), bird-footed checkerbloom (Sidalcea pedata), four of the southern California national for- slender-petaled mustard (Thelypodium ests (fig. 2.31) (fig 2.32). The habitat type stenopetalum), and California dandelion covers an estimated 55,446 acres in southern (Taraxacum californicum), are found in California, 38 percent (21,070 acres) occur- meadow habitat in the San Bernardino Moun- ring on public lands. tains. The San Bernardino blue grass also Meadows can be characterized as wet, dry, occurs in montane meadows within San Di- or alkaline but are usually mesic, even in late ego County. summer. Due to rainfall patterns they tend to A survey of sixty-two meadows on the occur at lower elevations in the northern parts Cleveland, San Bernardino, and Angeles na- of California and shift to higher elevations in tional forests and three state parks was the southern areas of the state (Holland 1986). conducted in 1994 and 1995 (H. Gordon, Re- Two physical conditions characterize mead- mote Sensing Lab, unpubl.data). Some of the ows: 1) a shallow water table usually within meadows sampled are shown in table 2.17. two feet of the soil surface in mid-summer and The largest meadows in the assessment 2) surface soil material that is fine-textured area are found in the mountains of San Diego (i.e., a clay) and richly organic (Wood 1975). County, but the majority of these are located Meadow soils are poorly draining relative to on private lands (e.g., Cuyamaca, Mendenhall, the coarser soils of adjacent forest vegetation French, and Dyche meadows). Other expansive (Holland 1986). 49 Figure 2.31. The distribution of montane meadows in southern California.

meadow systems are found in the San Jacinto named meadows near Lockwood, Grade, and Mountains, with the largest located in Gar- Cuddy valleys, Mount Abel, and the San ner Valley. There are many meadows in the Emigdio Mesa area (J. O’Hare, Angeles NF, San Bernardino Mountains, but most are small in litt. 1998). in size. The San Gabriel Mountains contain very All meadow habitats are sensitive to ac- few meadows due to their steep topography, al- tivities and disturbances that affect stability though Big Pines Meadow is significant as the of the surface soil, especially during the win- primary location for the San Gabriel Mountains ter and spring when the ground is most blue butterfly (Plejebus saepiolus aureolus). In the saturated. Meadow systems, particularly those Castaic region, Knapp Ranch Meadow is esti- on steeper slopes, can develop gullies in re- mated to cover almost two hundred acres. sponse to disturbance. The best examples of Montane meadows on the Los Padres this are associated with road and trail systems National Forest include Toad Springs, Thorn, that increase the amount of runoff a meadow and Chula Vista meadows, Yellow Jacket Creek receives and cause soil erosion. Eroded areas (a series of stringer meadows), and several un- convey water at a higher rate, eventually lead- ing to the formation of gullies, which in turn 50 Chapter 2 seems to be in better condition overall (R. Minnich, UC Riverside, in litt. 1998). The Cleveland National Forest has devel- oped a habitat management guide for four sensitive plants that grow in riparian montane meadows: Cuyamaca larkspur (Delphinium hesperium ssp. cuyamacae), lemon lily (Lilium parryi), Parish’s meadowfoam (Limnanthes gra- cilis var. parishi) and San Bernardino blue grass (Winter 1991b). Figure 2.32. Montane meadow habitat at Bluff Lake, adjacent to the San Bernardino National Forest. An Pebble Plains endangered plant, the bird-footed checkerbloom, is Pebble plains have a very limited distribu- found here. LYNN LOZIER tion in the northeastern San Bernardino Mountains, occurring between elevations of channel water away from the meadow, effec- 6,000 and 7,500 feet. They are found only tively lowering the water table and removing within a 92-square-mile area near the city of increasing amounts of topsoil (J. O’Hare, Big Bear, on the San Bernardino National Angeles NF, in litt. 1998; M. Bearmar, Cleve- Forest and on adjacent private lands (fig 2.33) land NF, pers. comm.). (Neel and Barrows 1990). Some well-known When the water table of a meadow is low- sites include the Big Bear Lake complex, the ered, it allows for the steady encroachment and Sawmill complex, Gold Mountain, North establishment of nonmeadow flora. Runoff Baldwin Lake, Arrastre Flat/Union Flat, from road and trail systems appears to be one Holcomb Valley, south Baldwin Ridge/Erwin of the greatest impacts to meadow habitats Lake, Onyx Ridge/Broom Flat, and Coxey within the assessment area. Recurrent tram- Meadow. Three hundred and seventy-nine pling by livestock, vehicles, or people can also acres of pebble plain habitat are mapped in introduce soil erosion and cause gullying. Over our GIS database, 60 percent located on pub- time gully systems may become stabilized and lic lands. The Pebble Plain Habitat form riparian habitat, much like what has oc- Management Guide and Action Plan cites 546 curred at Knapp Ranch on the Angeles acres of pebble plain habitat with 94 percent National Forest and Thorne Meadow on the occurring on public lands (Neel and Barrows Los Padres National Forest (J. O’Hare, Ange- 1990). les NF, in litt. 1998). The plains appear as distinct open patches Many montane meadows on national for- within forest and woodland vegetation often est system lands have historically been dominated by Jeffrey pine, pinyon, and juni- impacted by the overgrazing of livestock per species (fig. 2.34). Remnants of a huge (Krantz 1983; M. Borchert, Los Padres NF, ice-age lake bottom (Krantz 1983), the plains pers. comm; J. O’Hare, Angeles NF, pers. are part of the Mohave crustal block uplifted comm.). Excessive grazing is believed to shift during Quaternary time (Derby and Wilson floral composition from native perennials to 1979). They are treeless, deep clay deposits non-native annual species (Winter 1991b) and that support a rare assemblage of plants remi- the current trend on national forest system niscent of an alpine flora. This flora consists lands has been to reduce the number of cattle of small cushion-forming plants, tiny annu- in these areas or remove them completely from als, grasses, and succulents. The plants are all especially sensitive locations. However, the in- well spaced, low growing, and sun tolerant, vasion of alien taxa appears to be a greater yet exact floral composition varies between problem in lower elevation meadows rather sites. The substrate consists of clay soil (up to than at higher elevations, where the habitat 51 Table 2.17. A partial list of montane meadows on the Cleveland, San Bernardino, and Angeles national forests and Palomar Mountain State Park. The assessment of meadow condition is based on notes taken by H. Gordon during her field surveys in 1994 and 1995. Acreages reported are visual estimates.

Meadow Name Water Source Date of Assessment of Meadow Sampling Characteristics and Condition Cleveland NF Guatay runoff from Guatay Mtn. 5/95 upper area type converted?, drainage channel, structures; 10-50 acres Laguna Big and Little Laguna 7/95 some erosion in the channeled area of lakes, Boiling Springs, the check dam, Prado area has cattle; Escondido, Chico, and 500-600 acres Los Rasalies ravines, Agua Dulce Creek Lost Valley Caliente Creek, spring 5/95 horses, portion of meadow in private ownership, dispersed camping; 50-100 acres Love Valley upland runoff 7/94 50-100 acres Mendenhall Iron Springs Creek 6/95 historic and recent cattle grazing; 100- 200 acres Organ Valley spring-fed 6/95 RNA for Engelmann oak; 5-10 acres Roberts Ranch upland runoff 5/95 gullies caused by runoff from I-8, cattle, recent acquisition; 100-200 acres Tenaja upland runoff, springs 5/95 type conversion from chaparral? 100- 200 acres San Bernardino NF Baldy Mountain unknown 7/95 jeep trail, horse-holding structures, cattle, adjacent to fire break; 50-100 acres Big Meadow Santa Ana River 8/95 lower portion of meadow affected by upstream gullying, the encroachment of Great Basin sagebrush, and non-native species; 50-100 acres Broom Flat Arrastre Creek, runoff 7/95 cattle; 50-100 acres Coxey springs, Coxey Creek 8/95 non-native species in northern area of meadow; 10-50 acres Garner Valley South Fork of San 7/95 some soil erosion, cattle; >300 acres Jacinto River Holcomb Valley Holcomb and Caribou 8/95 historic gold mining and ranching in the creeks Belleville area; 50-100 acres South Fork South Fork of Santa 9/95 irrigation ditch in upper meadow area; Ana River 10-50 acres Tahquitz Tahquitz Creek 9/95 Jeffrey pine encroaching on lower meadow, trail; 10-50 acres Angeles NF Big Pines seasonal Mescal Creek 6/95 wet meadow easily accessible, retreating system due to expansion of Mountain High Ski area parking lots, presence of San Gabriel Mtns. blue butterfly; <5 acres Brown’s Flat overland flow 6/95 in the San Dimas Experimental Forest; 50-100 acres Knapp Ranch seasonal Castaic Crk system 5/95 100-200 acres Palomar State Park Lower French French Creek 5/95 some channelization, adjacent forest burned Upper Doane Doane Creek 6/95 not grazed regularly since 1940s, some erosion, small channel; 50-100 acres Chapter 2

Figure 2.33. Occurrences of pebble plains and carbonate outcrops in the eastern San Bernardino Mountains.

53 percent) mixed with quartzite pebbles and ation of the Big Bear Lake reservoir in the gravel that are continually pushed to the sur- 1800s. More recently the habitat has declined face through frost action (Holland 1986; Neel in amount and quality primarily from vehicle and Barrows 1990). The combination of clay activity on the sites (Neel and Barrows 1990). soil, frost heaving, extreme annual and daily Some pebble plains have been completely temperature fluctuations, high light intensity, devegetated (e.g., upper Sugarloaf). The habi- and dessicating winds is thought to prevent tat is especially vulnerable to damage from the establishment of tree species onto the vehicles when the ground is saturated. Deep plains (Derby and Wilson 1979). Three fed- ruts are created in the soil that directly affect erally listed plants, Big Bear Valley sandwort the vegetation and alter the surface hydrology (Arenaria ursina), ash-gray Indian paintbrush of the plains. (Castilleja cinerea), and southern mountain The Pebble Plain Habitat Management buckwheat (Eriogonum kennedyi var. Guide and Action Plan was developed by the austromontanum), are found on pebble plains. San Bernardino National Forest to provide An estimated 150 acres of pebble plain management direction for long-term conser- habitat are believed to have been lost by cre- vation of pebble plains and the rare plants 53 Carbonate is named for its primary con- stituent, calcium carbonate. The substrate is an alkaline, sedimentary rock type that weath- ers into limestone and dolomite soils. A number of plants are endemic to these car- bonate soils (see carbonate plant group, chapter 5). On a broader scale, carbonate out- crops support desert montane plant communities such as blackbush scrub, pinyon- juniper woodlands, Jeffrey pine-western juniper woodlands, and Joshua tree woodlands Figure 2.34. Pebble plain habitat at Gold Mountain, (USFWS 1997b) (fig. 2.35). San Bernardino National Forest. Plants in this habitat High-grade carbonate deposits in the San type are diminutive and alpine-like. Despite their Bernardino Mountains are mined for com- appearance, pebble plains have high floral diversity. mercial use; the carbonate in these mountains MAILE NEEL is one of just three high-quality deposits in the western United States (Krantz 1983, assocated with them. Closure of unauthorized 1990). Limestone is used in a number of com- vehicle routes through pebble plain habitat (in- mercial applications and almost all of the cluding walk-throughs that discourage habitat on public land is under mining claims. motorcycle access and barriers to prevent ve- Mining activities such as the direct removal hicle access), signage, increased patrol, mineral of soil, road development, and dumping of withdrawal, habitat acquisition, removal of overburden rock, have led to an overall de- non-native grasses, and public education are cline in the amount and quality of carbonate actions being taken to protect and enhance habitat. Plant communitites associated with the habitat. Conserving pebble plain habitat this habitat are slow to recover from distur- over a broad geographic range, reducing bance due to the low productivity, thin soils, fragmention, and encouraging compatible uses and very dry climate on the desert side of these are Forest Service goals for this habitat. mountains (Rowlands 1980). The high levels of ground disturbance as- Limestone/Carbonate Outcrops sociated with mining, the potential for Carbonate outcrops are found along the additional claims to become active, and in- desert-facing slopes of the San Bernardino sufficient protection mechanisms necessitated Mountains. Located mainly within the San Bernardino National Forest, these soil depos- Figure 2.35. Carbonate habitat north of Holcomb its extend for approximately twenty miles Valley in the San Bernardino Mountains. A low- along an east-west axis and occupy an esti- growing plant, the endangered cushenbury mated 21,000 acres. Over 18,000 acres of these buckwheat, can be seen in the foreground. TIM KRANTZ unique soils are within the assessment area, of which 87 percent are on public lands (fig. 2.33). Disjunct outcrops occur just south of Sugarlump Ridge and to the east as far as the Sawtooth Hills (USFWS 1997b). The U.S. Fish and Wildlife Service Draft Recovery Plan reports a higher amount of total carbonate habitat (32,620 acres) though subsurface de- posits may account for the additional acres (USFWS 1997b).

54 Chapter 2 the federal listing in 1994 of five rare plants range from green to blue to red. Generally high endemic to carbonate (Neel 1997). This law in magnesium (consisting mainly of hydrated created a rare situation where two very promi- magnesium silicate) and low in calcium, ni- nent laws (the 1872 Mining Law and the 1973 trogen, and phosphorous, the soil is considered Endangered Species Act) appear to conflict impoverished and supports only those plants with one another. adapted to or tolerant of its unique chemis- To resolve this issue, a collaborative effort try. It contains varying amounts of heavy has been initiated among the San Bernardino metals (e.g., cobalt, nickel, and iron) that con- National Forest, the Bureau of Land Manage- tribute to its color (J. O’Hare, Angeles NF, ment, the U.S. Fish and Wildlife Service, mine pers. comm.). operators, researchers, and other affected par- In its favor, serpentine often has a higher ties, to design a reserve system for these plants water-holding capacity than adjacent soils (i.e., and their habitat (G. Zimmerman, San Ber- it forms clay soils). Grassland, chaparral, oak nardino NF, in litt. 1998). The Carbonate woodland, and conifer forest may all form on Endemic Plant Conservation Strategy is be- a serpentine substrate, but species richness and ing designed to incorporate many large density is always much lower than on adja- occurrences of the five listed plants over a wide cent nonserpentine soils (Kruckeberg 1984). range of habitat mosaics throughout their geo- Extreme serpentine habitats are referred to as graphic ranges. Buffers to minimize conflicts “barrens” because they support little or no and to ensure defensible areas, connections vegetation. Less toxic sites can support up to between populations and habitats, and inclu- 215 species and varieties of plants and at least sion of sites that contain more than one listed nine species and subspecies of butterflies species are other important elements being (Schoenherr 1992). Sargent cypress and considered in the reserve design. Genetic re- knobcone pine are reliable indicators of a ser- search through patterns of isozyme variation pentine soil. Twelve of the plant species (Neel 1997), results of soil sampling, and a addressed in this assessment are indicators of detailed vegetation classification combined or endemic to serpentine soils. Of these, ten are with field studies of individual plant occur- classified by the regional forester as forest service rences are being completed and will provide sensitive on the Los Padres National Forest (see information necessary for the reserve design. serpentine plant group in chapter 5). GIS coverages of plant locations, carbonate The Cachuma Saddle area and Figueroa rock locations, proposed and approved future Mountain, both in the San Rafael Range, con- mining activities, land use conflicts, and other tain serpentine chaparral and woodland, resource values have been developed in the including groves of Sargent cypress. Serpen- Conservation Study for Five Carbonate Plant tine woodland and Sargent cypress occur again Species: a study of land use conflict in the San at Cuesta Pass and West Cuesta Ridge in the Bernardino National Forest (USDA Forest Ser- southern Santa Lucia Range. Further north, vice 1996). the Chew’s Ridge area in the Santa Lucia Ranges contains good examples of serpentine Serpentine Outcrops grassland and woodland. Serpentine grassland Serpentinite rock outcrops occur within is also found in the Pine Ridge area of the Santa the assessment area in the Santa Lucia Ranges, Lucia Ranges (Kruckeberg 1984). the southern Los Padres region, and at one Serpentine is an indicator of economic locality in the Santa Ana Mountains. Within metals; quicksilver (mercury), chromium, the boundaries of the Los Padres Natonal For- nickel, magnesite, asbestos, talc, soapstone, est are an estimated 31,470 acres of and jadeite are all found in association with serpentinite-derived soil (fig. 2.36). serpentine and other ultramafic outcrops. A This soil, commonly called serpentine, is number of historic and active mines occur in recognized by its waxy texture and colors that 55 Figure 2.36. The distribution of serpentine outcrops on the Los Padres National Forest.

the Santa Lucia Ranges and potential exists California, with 74 percent located on public for mining activities to adversely impact ser- lands (Hardham 1962). A small amount is pentine habitat on the forest (Kruckeberg found on U.S. Army Fort Hunter Liggett 1984). Military Reservation and 880 acres are re- ported on the Los Padres National Forest (Los Sargent Cypress Groves Padres NF 1988a). Sargent cypress (Cupressus sargentii) groves Three substantial groves occur on the for- are scattered within the assessment area in the est at Zaca and Alder peaks and in the Cuesta Santa Lucia Ranges and southern Los Padres Ridge Botanical Area (fig. 2.38). At least six region. Groves are distributed from 650 to additional sites are also located in the Santa 3,300 feet elevation. The species is considered Lucia Ranges (D. Wilken, Santa Barbara the most wide-ranging cypress in California Botanic Garden, in litt. 1998).The grove at (fig. 2.37). Based on Clare Hardham’s map- Cuesta Ridge in the southern Santa Lucias is ping effort, an estimated 1,585 acres of Sargent the southernmost large occurrence and one of cypress habitat occur in central and southern several isolated groves ranging from northern Mendocino County south to Zaca Peak in 56 Chapter 2 Santa Barbara County. The Zaca Peak site, lo- Factors other than soil affect the distribution cated near the San Rafael Wilderness Area, is of Sargent cypress, however, as it occupies less much smaller than the occurrence at Cuesta than three percent of serpentine habitat on the Ridge (Jenkins 1981). In the Santa Lucia forest. The tree grows on rocky slopes, ridges, Ranges, the majority of groves are located and raised stream benches and terraces (Saw- along the main ridgeline at about 2,500 feet. yer and Keeler-Wolf 1995). Throughout most The tree may be more prevalent at these sites of its range Sargent cypress occurs with gray due to heavy fog occurrence (Hardham 1962). pine, Coulter pine, scrub oak, leather oak, and Sargent cypress is also located along a ridge buck brush (Johnston 1994). It also frequently formed by the King City Fault near Bryson grows with California bay, interior live oak, and at lower elevations in the Los Burros Creek and knobcone pine. Muir’s hairstreak butter- drainage. fly is strongly allied with Sargent cypress. Sargent cypress is an indicator of serpen- Like other cypress, Sargent is adapted to tine soils and tends to occur with other and dependent on fire for seed dispersal and sensitive plant species (Los Padres NF 1988a). enhancement of germination. Fires that are

Figure 2.37. The distribution of Santa Lucia fir forest and Sargent cypress groves in central and southern California.

57 scale map of all known Santa Lucia fir stands (Talley 1974). Based on this map there are an estimated 7,576 acres of Santa Lucia fir for- est, with 95 percent located on public lands. The Los Padres Forest Plan however, cites 1,400 acres of Santa Lucia fir within the for- est boundary (Los Padres NF 1988). Stands occur in relatively inaccessible ar- eas: on steep north- or east-facing slopes, along ridges, in canyon bottoms, and on raised stream benches and terraces (fig. 2.39) (Saw- Figure 2.38. Sargent cypress and chaparral growing yer and Keeler-Wolf 1995). The tree may be on serpentine soil at Cuesta Ridge Botanical Area, dominant in stands or co-dominant with can- Los Padres National Forest. MALCOLM MCLEOD yon live oak. At lower elevations it occupies the same habitats as coast live oak, Pacific too frequent, however, prevent adequate seed madrone, and coast redwood. At higher el- production and can extirpate entire groves evations it grows with tan oak, interior live (Esser 1994b). South of an existing Waterdog oak, and incense-cedar (Johnston 1994). Creek grove, a cypress “swamp” is believed to Occurrences range from a low point at have been extirpated by fires in 1953 and 1960 Big Sur Gorge to the top of Cone Peak but (Hardham 1962). The tree has a low-branch- greater than half of the fir’s distribution is ing habit that makes it susceptible to crown above 3,200 feet (Talley 1974). The south- fire and is often killed in wildfires. Required ernmost stands occur at lower elevations in fire-free time intervals are not well defined for San Luis Obispo County. These stands are the species but might be consistent with other found along coastal drainages sometimes cypress in California (Esser 1994b). adjacent to redwood (Sequoia sempervirens). Sargent cypress is generally not considered Occupied drainages include Marmolejo a rare tree and has no legal status. However, Creek, Jackson Creek, the Big Sur River, the because it is localized on serpentine soil and west and main forks of Limekiln Creek, because some groves, particularly on the Hare Canyon, and Villa Creek. The species Monterey Ranger District, have been reduced is also found along north- and east-flowing in size by short fire-return intervals, Sargent drainages including the Carmel River, Miller cypress communities are considered rare on Fork, Anastasia Canyon, Church Creek, Zig forest system lands (M. Borchert, Los Padres Zag Creek, Higgins Creek, the Arroyo Seco NF, pers. comm.). River, the San Antonio River, the Negro Fork of Nacimiento River, and San Miguel Santa Lucia Fir Forest Creek. Santa Lucia fir (Abies bracteata), also Based on physical characteristics of the known as bristlecone fir, is found in the north- sites it occupies (rocky areas with low fuel ern Santa Lucia Mountains of Monterey loads), Santa Lucia fir is generally regarded as County. The tree is narrowly distributed in intolerant of fire, yet some mature stands have an area about thirteen miles wide and fifty- survived wildland fires (J. Kwasny, Los Padres five miles long in the Ventana Wildernes area NF, pers. comm.). Talley looked at the fire of the Los Padres National Forest and a por- history of Santa Lucia fir and determined that tion of U.S. Army Fort Hunter Liggett, there were few differences between past and bordering the forest on the east (fig. present fire intensities within stands, despite 2.37)(Schoenherr 1992). As part of his changing fire regimes in California overall. Fire master’s thesis, Steve Talley produced a coarse- suppression activities such as fire lines and

58 Chapter 2 fuelbreaks are not currently allowed in stands Disjunct (Locally Rare) on the Los Padres National Forest. Fire is not Communities prevented from burning through stands nor is it directed toward stands. Two disjunct plant communities were Several naturalists, beginning with Sargent identified in the assessment area. These com- in 1898, have recognized Santa Lucia fir as a munities are relatively common in other areas, species at risk due to its narrow endemism and but are rare or highly localized within the as- susceptibility to cone parasites (Talley 1974). sessment area. They are briefly described Occurrences of Santa Lucia fir appear stable below. at this time; however, a recently recognized Aspen Groves threat is the invasion of non-native species into Quaking aspen (Populus tremuloides) is a the understory. The rhizomatous shrub French wide-ranging tree in North America, but its broom (Genista monspessulana) is particularly distribution is patchy in the Californias. It is invasive and difficult to eradicate once estab- widespread in the Sierra Nevada and there are lished. It directly competes with seedlings of substantial stands in the White Mountains and Santa Lucia fir and other native understory in Baja California’s Sierra San Pedro Martir. species (J. Kwasny, Los Padres NF, pers. However, aspen is essentially absent in the comm.) southern California mountains with the ex- ception of two small groves in the San Bernardino Mountains: one on Fish Creek in the San Gorgonio Wilderness Area and the other on upper Arrastre Creek (Thorne 1977). Figure 2.39. A stand of Santa Lucia fir at Cone Peak, These two occurrences combined cover less Monterey Ranger District, Los Padres National Forest. than fifty acres, all of which are located on JEFF KWASNY national forest system land. A third grove, re- portedly mapped in 1935 by D. Axelrod, may still exist west of Lake Arrowhead (Jones 1989). The groves are found on decomposed granite at the bottom of canyons and on slopes along creeks. The Arrastre Creek aspen grove occurs along a seasonal watercourse. It is found mainly with xeric plants (i.e., sagebrush scrub, pinyon, Jeffrey pine forest) and endures a dry summer climate. Aerial photographs from 1972 and 1983 indicate that the grove is de- creasing in size (Jones 1989). The Fish Creek aspen grove also occurs along a drainage in what is otherwise a Jeffrey pine and subalpine forest. Beavers were introduced into the habi- tat and subsequently reduced this grove by an estimated 25 to 50 percent (Jones 1989). Evidence indicates that the tree was once more common in the mountain ranges of southern California and migrated into north- ern Baja during prehistoric times (Oberbauer 1986). Aspen is a clonal organism and the San Bernardino Mountain populations were 59 analyzed and found to be almost genetically identical to each other (Zona 1989).

Knobcone Pine Stands Disjunct stands of knobcone pine (Pinus attenuata) occur naturally in the assessment area at just a few locations: in the northern Santa Lucia Range of Monterey County, in San Luis Obispo County at Cuesta Pass, in the western San Bernardino Mountains, and in the Santa Ana Mountains (Vogl et al. 1977). There are approximately 1,233 acres of knobcone pine habitat mapped at these loca- tions, 85 percent of which is located on public lands. The species is more common through- out northern California and also grows near Ensenada, Mexico. Knobcone pine has been reported from sea level to over 5,500 feet, though stands usu- ally occupy a transitional zone between lower chaparral/woodland and higher elevation co- nifer forest (Vogl et al. 1977). Talley and Griffin (1980) and Griffin (1982) report on the fire ecology of knobcone pine in the north- ern Santa Lucia Range. Similar to Coulter Figure 2.40. Knobcone pine near Cuyama Grade, pine, knobcone pine has serotinous cones and Los Padres National Forest. JANET NICKERMAN is dependent on fire for seed dispersal (Vogl 1976). In the San Bernardino Mountains, stands of knobcone pine cover approximately 990 acres between City Creek and Government Canyon. In the Santa Ana Mountains, small stands of this pine occur in otherwise chapar- ral-dominated areas on the slopes of Sugarloaf, Pleasants, and Santiago peaks (Thorne 1977; F. Roberts, USFWS, pers. comm.). The stand at Pleasants Peak grows on serpentine soils (EA Engineering, Science, and Technology 1995). Usually restricted to dry, rocky sites with shal- low soils, knobcone pine is typically associated with infertile substrates that limit competition from other conifers (Holland 1986) (fig. 2.40).

60