Madrono, Vol. 59, No. 2, pp. 47-108, 2012 FLORA OF THE CARQUINEZ STRAIT REGION CONTkA COSTA AND , - SOLANO COUNTIES, CALIFORNIA Dean G. Kelch1 2 and Andrew Murdock2 'CDA Herbarium, Plant Pests Diagnostic Laboratory, Department of Food and CA Agriculture, Sacramento, 95832 CA 2University and Jepson Herbaria, University of California, Berkeley, 94720 [email protected] Abstract The Carquinez Strait region is an area in the northeastern San Francisco Bay Area of California characterized by typical coastal lowland California vegetation dominated by oak woodland, grassland, and coastal scrub. From 1996 through 2010, an inventory of vascular plants was amassed. Of the 795 taxa found within the study area, 13 are ferns, 4 are gymnosperms, and 778 are angiosperms. Of eudicots and monocots, 41% (249) and 46% (79) respectively, are adventives introduced since European colonization. Despite the accessibility of the region and the proximity of institutional herbaria, relatively few collections were made in the study area before the beginning of this study. Key Words: California, carquinez, contra costa, flora, solano. Introduction of fresh and saltwater; water diversion upstream has led to increased salinity in much of the strait Description of Area (Conomos 1979). The mouth of the Napa River (Mare Island Strait), northwest of the Carquinez Circumscription. The Carquinez Strait runs Strait, is also tidal, as is Pacheco Slough on the east to west from the Suisun Marsh to San Pablo southeastern border of the study area. Streams Bay, California. The Suisun Marsh is the area of that flow west into the bay, e.g., Pinole and confluence of the two largest river systems of Franklin creeks, serve as conduits for coastal fog California, the Sacramento River System, which and have a slightly different biota than streams drains the northern interior of the state, and the that flow north or south into the strait, e.g., San Joaquin River System, which drains the Alhambra Creek. Smaller streams drain from the southern interior of the state. San Pablo Bay ridges; some, such as Alhambra Creek, Big Bull comprises the northern portion of San Francisco Valley Creek, and Edwards Creek are perennial Bay. The study area comprises lands adjacent to streams; most are intermittent in nature and dry the Carquinez Strait, forming an area whose during the summer and fall. borders are the shore of San Pablo Bay to the west, Pacheco Slough to the east, the Lake Climate. The study area, as with the surrounding Herman Valley and Austin Creek to the north, regions, has a Mediterranean-style climate with and Pinole and Alhambra Creeks to the south warm, dry summers and cool, wet winters. July, (Fig. 1). The lands to the north and south of the August, and September have little measurable strait are in Solano and Contra Costa counties, rainfall. Mean annual precipitation varies from respectively. This area is approximately 22 km 46 cm of rain each year in the eastern sector from east to west and 16 km from north to south. (Martinez) to 56 cm of rain each year 2 km southwest ofthe area at Point Richmond (National Notable features. The study area (Fig. 1) is Weather Service 2010). The western portion of the dominated by dissected ridges running in a roughly study area receives extra moisture in the form of west-northwest direction. To the north of the strait summer fog that enters San Pablo Bay via the is Vallejo Ridge, with peaks around 170 m. To the Golden Gate. Annual mean minimum temperature south of the strait are Carquinez (the smallest), in January is 4 C in the east and 5.5°C in the west. Franklin, and Pinole Ridges, with the tallest peaks Frosts, although not common, occur one to seven of the latter two reaching about 300 m. nights in a typical winter, being more common in The dominant waterway is the Carquinez Strait the east. Annual mean maximum temperature in km itself; it is ca. 1.5 wide at the Benicia Bridge in July is 31.5C in the east and 22°C in the west. the east and ca. 0.95 km wide near the Carquinez Bridge to the west. The strait is subject to tidal GeologyIsoils. The origin of the Carquinez action. Originally the strait was an area ofmixing Strait appears linked to the uplift of the east . MADRONO 48 [Vol. 59 Fig. 1. An aerial photograph showing major collecting localities and the borders of the Carquinez Strait Region as defined in this study. The inset shows the location of the region within California. Numbers on the photograph indicate localities in Appendix 1 San Francisco Bay region (Graymer et al. 1994, redberry (Rhamnus croeea), and winecup fairyfan 2002). By the late Miocene (ca. 9.5 Ma) the (Clarkia purpurea subsp. purpurea) uniquely region was uplifted and formed the western shore occur in the study area. On outcrops of Neroly of an embayment (Graham et al. 1984). The sandstone, such as Ozol Rock, one finds the Carquinez Strait opened about 0.6 Ma and locally uncommon plant community chaparral drained a large, short-lived, freshwater lake supporting plants such as chamise {Adenostoma (perhaps lasting 50,000-100,000 years), which fasciculatum), chaparral paintbrush (Castilleja occupied the present-day San Joaquin Valley foliolosa), and Mount Diablo fairy lantern (Sarna-Wojcicki et al. 1985). (Calochortus pulchellus). The bedrock of the Carquinez Strait area is Small exposures of tuff (derived from volcanic almost exclusively sedimentary. Most of it was ash-fall) occur near Rodeo and Pinole, where formed from erosion products deposited in locally uncommon plants such as perennial marine settings: sandstones of varying composi- salsola (Salsola australis), California shadscale tions, conglomerates, shales, siltstones, mud- (Atrip/ex californica), and sticky sandspurrey stones, and claystones deposited from the late (Spergu/aria macrotheca var. macrotheca) occur Cretaceous (99 to 65 Ma) to the middle Tertiary on the bluffs. Clay lenses occur in small patches (Miocene, ca. 10 Ma). Later sedimentary rocks along the north-facing slopes bordering the strait. (end of the Miocene to the beginning of the These soils support clay endemics, such as Pliocene) were generally deposited in terrestrial Jepson's eryngo (Eryngium jepsonii) and clay settings as the local region was uplifted and the mariposa-lily (Calochortus argillosus). terrane comprising the nascent Coast Ranges closed off from the Pacific Ocean what would History of Land Use become the Great Valley. The units and forma- tions generally trend along a northwest-southeast Indian. The Karkin tribe (whence the name axis paralleling the major faults in the area. Carquinez) was a northern element of the Ohlone Vegetation differences are noted where bedrock is (Costanoan) language group that occupied both exposed, such as Pinole Peak where imbricate sides of the Carquinez Strait (Heizer 1978). phacelia (Phacelia imbricata subsp. imbricata), Because the tribe was relatively small (hundreds) KELCH AND MURDOCK: CARQUINEZ FLORA 2012] 49 and their culture was disrupted early in European with the introduction of Old World plants colonization, little is known about the tribe. Their adapted to human-associated disturbance. Al- language was a distinct member of the Utian though there were native large herbivores, language family; only a vocabulary compiled in particularly black-tailed deer {Odocoileus hemi- the late 18th century survives (Beeler 1961). The onus subsp. columkianus) and tule elk (Cervus Karkin were bordered on the east by Yokuts and canadensis) (Jameson and Peeters 2004) in the to the north by Patwin. There was a settlement on study area before the advent of Europeans, the the shore of what is now Vallejo, where members practice of repeated, concentrated cattle grazing of various tribes gathered to trade, as is created conditions under which introduced weeds documented by archeological remains (Davis could flourish and spread. Region-wide, the effect 1974). We assume that, like other Ohlone of this was to increase the beta (overall) diversity tribelets, the Karkin's staples comprised seeds, of the flora (note the large proportion of the bulbs, and fruits, especially acorns, supplemented reported flora that is not native to California). with game and seafood (Margolin 1978). Some of The alpha (site-specific) diversity of some sites the plants consumed by the Ohlone include seeds subject to intensive grazing was reduced as cattle- of dock, tarweed, buckeye, and California bay tolerant taxa replaced native taxa in some areas. laurel. Acorns are a notoriously variable food In particular, the replacement of native perennial source; early Californians managed their envi- grasses and forbs by non-native annual grasses ronment by pruning, burning, and reseeding to and forbs is notable in the study region, as it is maximize plant and animal production (Margolin throughout much of California (Crampton 1974; 1978). These vegetation manipulations most Heady 1977). likely had a significant, but unknown, effect on Development. After the initial development in the flora. the 19th century, urban growth in northern European. The advent of European and Latin Contra Costa and southern Solano counties was American immigrants has had a profound effect modest. As the road system developed in on the flora of the region. Most of the land California, the main commercial arteries shifted included in the study area is hilly and unsuitable away from the waterways and the study area for intensive agriculture. Most flat areas are became a relative backwater. This began to located along the shores near alluvial deposits. change in the last decades of the 20th century, These areas were ideal for settlements, as they as rising population and real estate prices drove were easy to build on, near the major water- people to search for housing farther from San transporation routes, and had access to fresh Francisco. This second wave of residential water from perennial streams. By the end of the growth was more intense in certain portions of 19th century, Vallejo, Martinez, Benicia, and the study area (e.g., Vallejo and Martinez) than in other settlements were well established. Although others (e.g., the central northern portion of these urban areas covered a relatively small Contra Costa County) due to local zoning percentage of the land within the study area, restrictions, resident resistance to suburban they had a disproportinate impact on wetlands of sprawl, and acquisition of land as permanent various types that occurred predominantly in the open space (Entrix, Inc. unpublished data). low, flat areas chosen for habitation. In the early 20th century, large areas of salt marsh were filled Open space. The establishment of the East Bay and developed to provide space for industries Regional Parks District in 1934 has had profound effects on the preservation of the local flora in the such as oil refining, smelting, brick manufacture, and sugar production, as well as direct access to area south of the Carquinez Strait. Tracts of land shipping. In addition, demand for wood for within the study area are preserved within the domestic use near houses and for the trains that Carquinez Strait Regional Shoreline, Martinez Shoreline, and Point Pinole parks. Larger areas soon plied the railway built along the southern adjacent to these parks and along Franklin Ridge shore of the strait led to removal of trees from many of the drainages adjacent to these areas of are partially preserved through zoning that allows only sparse development (Contra Costa activity. In some denuded areas between the towns of Crockett and Port Costa, groves of blue County 2005). In addition, the Muir Heritage gum {Eucalyptus globulus) were planted to Land Trust preserves significant portions of Franklin Ridge as open space. The John Muir provide lumber and, as "plantation lands," tax breaks. Although these introduced trees have not National Historic Site, managed by the National spread significantly beyond their original groves, Park Sevice, preserves land in Martinez once owned by Muir family, including Mount Wanda, they have largely prevented the reestablishment the Muir House property, and the Muir-Strenzel of native vegetation in these areas. gravesite along Alhambra Creek. In the northern Agriculture!cattle. Perhaps the most profound portion of the study area, there are fewer biotic changes to the study area resulted from the naturally vegetated parks. Significant natural wide-scale development of ranching combined areas are preserved in Benicia State Recreation MADRONO 50 [Vol. 59 Area and Mare Island, and in northern Benicia southern portion of the study area in its (south and west of Lake Herman). treatment. The Flowering Plants and Ferns of Mount Diablo, California (Ertter and Bowerman A Wildlife conservation. major goal of wildlife 2002) treats a botanically rich area located management in California has been to increase km approximately 20 east-southeast of our study the number of black-tailed deer (Smith 2000). area. Other floras of nearby areas that were The increase in the population of the black-tailed useful in this study include Marin Flora (Howell deer in the study area during the latter half of the et al. 2007), Flora of the Mount Hamilton Range 20th century has had an unknown, but probably (Sharsmith 1945), A Flora of Sonoma County significant, impact on the vegetation. In certain (Best et al. 1996), Plants ofthe San Francisco Bay areas, a distinct browse zone may be identified, Region: Mendocino to Monterey (Beidleman and creating a clear area underneath oaks. Deer Kozloff 2003), A Flora of the Marshes of browsing has not seemed to prevent the estab- California (Mason 1957), and Flora of the Santa lishment of coastal scrub on road verges and Cruz Mountains of California (Thomas 1961). other previously grassy areas excluded from cattle grazing. A significant predator of deer is the puma Plant Associations (Felis concolor). Protection of puma by the Prior to this survey, descriptions of vegetation California Department of Fish and Game has types for Mount Wanda were made by E. Jepsen, led to an increase in the numbers of this large cat. P. B. Murdock, and A. G. Murdock (unpub- Pumas have been sighted within the southern lished data) and J. C. Hunter, S. D. Veirs, and P. portion of the study area. The direct effect of Reeburg (unpublished data). These types include these deer predators on the flora would be grassland, blue oak woodland, mixed evergreen negligible, but as population numbers increase forest, chaparral, and ruderal. Our initial surveys they may have an indirect effect on the flora via were performed to verify this assessment. This deer behavior and population size as documented information is summarized below, along with in Utah (Ripple and Beschta 2006). descriptions of additional vegetation types (e.g., The introduction and establishment of wild riparian, brackish marsh) not included in the turkeys (Meleagris gallopavo) into northern earlier studies. California in the 1960,s and 1970's, represents a change in the biota. Wild turkeys have become Blue oak woodland. Represented by a diverse common in the study area and some environ- assemblage of trees and herbaceous plants and mentalists fear that their presence is having has a distinct, well-developed overstory and negative impacts to populations of native plants understory. It typically occurs in north-facing (Daniel Gluesencamp, Audubon Canyon Ranch areas of Mount Wanda and in upper portions of personal communication). There is evidence that drainages. The dominant species in the overstory a turkey closely related to and possibly conspe- is blue oak (Quercus douglasii), with valley oak cific with M. gallopavo occurred in Northern {Quercus lobata), black oak (Quercus kelloggii), California approximately 10,000 years ago and California buckeye (Aesculus californica) also Common (Steadman 1980). If this is the case, then current well represented. understory species turkey establishment represents a reintroduction include poison oak (Toxicodendron diversilobum), of a native taxon to California. Turkeys may ripgut brome (Bromus diandrus), Pacific snake- affect the current ecological dynamic and thereby root (Sanicula erassicaulis), spring vetch (Vicia modify native vegetation. sativa), canyon nemophila (Nemophila hetero- phylla), chickweed (Stellaria media), miner's lettuce (Claytoniaperfoliata), goose grass (Galium Other Local Floras aparine), Italian thistle (Carduus pyotocephalus), hedgehog dogtail (Cynosurus echinatus), wild oats One inspiration for the current project was a (Avena fatua), and field hedge parsley (Tori/is plant list produced for the John Muir National arvensis). Historical Site commissioned by the National Park Service (E. Jepsen, P. B. Murdock, and A. Mixed evergreenforest. Characterized by dens- G. Murdock unpublished data). In addition, er forest than blue oak woodland. The overstory there was a large plant list produced for the is significantly more developed than the under- environmental assessment of Carquinez Strait story. Mixed evergreen forest generally occurs in Regional Shoreline (comprising a significant lower portions of drainages and on lower, north- portion of the southern section of the study area) facing slopes. Dominant tree species include coast based mostly on the work of the East Bay live oak (Quercus agrifolia) and California bay Chapter of the California Native Plant Society (Umbellularia californica), with black oak and (CNPS) volunteers, especially Dianne Lake (Lake California buckeye also occurring. Understory 2004). Barbara Ertter's Annotated Checklist of species include poison oak, maidenhair fern the East Bay Flora (Ertter 1997) includes the (Adiantum jordanii), California coffeeberry KELCH AND MURDOCK: CARQUINEZ FLORA 2012] 51 (Frangula californica subsp. californica), wood giant reed (Arundo donax). In some drainages, the fern (Dryopteris arguta), California blackberry native woody vegetation has been replaced by (Rubus ursinus), hedge nettle (Stachys rigida var. blue gum. In these areas, the depauperate quercetorum), and Torrey"s melic (Melica tor- understory is a scattering of the plants found in reyana). In more mesic areas, the understory is a typical riparian zone, as well as an occasional enriched with locally uncommon species such as adventive such as island cherry (Primus ilicifolia yerba buena {Clinopodium douglasii), false Solo- subsp. lyonii). mon's seal (Maianthemum stellatwn and M. racemosum), and madrone {Arbutus menziesii). Salt marshlbrackish marsh. Occurs in areas that border the Carquinez Strait and San Pablo Bay. The Chaparral. Consists of shrubs with some herb alpha diversity ofthis habitat is negatively correlated and tree components. In the study area chaparral with the salt concentration in the soil. Salinity levels is found in isolated patches on the south side and are highest in marshes that are diked and no longer crest of Western Franklin Ridge, Mount Wanda, subject to regular tidal flushing. In these areas, and at Ozol Rock. The dominant species is pickleweed (Salicornia pacifica) dominates the chamise (Adenostomafasciculatum var. fascicula- lower elevations. In higher areas at the base of tum). Other components include California sage- levees, salt grass (Distichlis spicata) also occurs. In brush (Artemisia californica), toyon (Heteromeles salt marshes subject to tidal action, these two arbutifo/ia), sticky monkeyflower (Mimulus aur- species are also dominant, but cordgrass (Spartina antiacus), coyote mint (Monardella villosa subsp. foliosa) may form patches on the margins of the villosa), and deer weed (Acmispon glaber var. marsh facing open water and alkali heath glaber). Other represented species include woolly (Frankenia salina) occurs mixed with salt grass A paintbrush (Castil/eja foliolosa), poison oak, in the high marsh. successful colonizer in these skullcap (Scutellaria tuberosa), and western blue- habitats is the introduced perennial peppergrass grass (Poa secunda subsp. secunda). (Lepidium latifolium), an aggressive spreader. In the eastern portion of the study area and near the Northern coasted scrub. Another shrub-domi- mouth of the Napa River, there is a greater influx nated vegetation type; this plant association is of fresh water leading to brackish rather than salt much more common than chaparral in the study marsh vegetation. Although the species men- area. The dominant taxa are coyote brush tioned above still occur, there are areas dominated (Baccharis pilularis var. consanguinea) and poison by other species, such as California bulrush oak; also, sticky monkeyflower is common. Other (Schoenoplectus californicus), common reed less common shrubs include hop tree (Ptelea (Phragmites australis), and alkali bulrush (Bol- crenulata), California gooseberry (Ribes califomi- boschoenus maritimus). Minor elements that occur cum var. califomicum), California coffeeberry, in these less saline marshes include hedge bind- and (rarely) Western leatherwood (Dirca occi- weed (Calystegia sepium subsp. limnophila), Cal- dentalis). Often, the understory is rich in herbs ifornia sunflower (Helianthus californicus), salt- such as yerba buena, wood fern, California marsh fleabane (Pluchea odorata var. odorata), cinquefoil (Drymocallis glandulosa var. wrangelli- western goldenrod (Euthamia occidentalis), salt ana), Pacific snakeroot, canyon nemophila, and marsh gumplant (Grindelia stricta var. an- bristly phacelia (Phacelia nemoralis subsp. nemor- gustifolia), sea lavender (Limonium califomicum), alis). There is a nearly bare border from 25-35 cm and Baltic rush (Juncus balticus subsp. ater). wide separating northern coastal scrub and grassland. This zone provides a unique habitat Ruderal. Areas that are more accurately for annual species, including skunkweed (Navar- described as a habitat than a true vegetation retia squarrosa), thyme-leaf mesamint (Pogogyne type, but a significant number of plants predom- serpylloides), round woolly-marbles (Psilocarphus inantly occur in such areas. They are disturbed tenellus), and petalless pearlwort (Sagina apeta/a). places that include fire roads, trails, roadcuts, and Northern coastal scrub is better developed where other areas created and consistently impacted by cattle grazing is limited or excluded. human use. This also includes areas that are regularly disked or mowed as part of a fire- Riparian. Vegetation along smaller streams and management regime. Disturbance favors fast- drainages generally consists of mixed evergreen growing annuals and plants that can withstand forest. Along larger, perennial streams typical trampling, mowing, soil compaction, and rapid riparian vegetation occurs. Dominant plants desiccation of surrounding soil. Significant plants include red willow (Salix laevigata), arroyo include little hop clover (Trifolium dubium), willow (Salix lasiolepis), periwinkle (Vinca ma- annual pepperweed (Lepidium nitidum), field jor), Himalayan blackberry (Rubus bifrons), and burweed (Soliva sessilis), bellardia (Bellardia poison oak. Other taxa include California black trixago), pineapple weed (Matricaria discoidea), walnut (Juglans hindsii), California grape (Vitis prickly sow thistle (Sonchus asper subsp. asper), californica), Western sycamore (Platanus race- bristly ox-tongue (Helminthotheca echioides), and mosa), Harding grass (Phalaris aquatica), and filaree (Erodium spp.). MADRONO 52 [Vol. 59 Annual grassland. Consists of mostly unshaded and names of notable geographic features within areas dominated by introduced grasses and the study area. In addition, we searched in some composites. It typically occurs in areas on tops taxonomic groups at the county level to ensure of hills, as well as on south-facing hillsides and inclusion of specimens collected within the study valley bottoms. Dominant taxa include: wild area. We examined specimens that represented oats, black mustard (Brassica nigra), rip-gut novel reports from the study area in order to brome, soft chess (Bromus hordeaceus), Italian confirm their identity. In order to include any ryegrass (Festuca perennis), foxtail barley (Hor- relevant specimens from California Academy of deum murinum subsp. leporinum), Italian thistle, Sciences (CAS), at the time minimally represent- CCH and yellow star-thistle (Centaurea solstitialis). ed in the database, we compiled a list of 43 Other significant taxa include common fiddle- taxa that had not been located in the study area neck (Amsinckia intermedia), milk-thistle (Sily- but were potentially present based on nearby bum marianum), cut-leaved geranium (Geranium occurrences and searched CAS for examples. We dissectum), crane's-bill geranium (Geranium also consulted a catalogue of specimens collected mo/le), various filarees, and spring vetch. In the by E. L. Greene, who was an important early northern region of the study area, where grazing plant collector in the San Francisco Bay Area. has been excluded, the perennial weeds fennel Specimens that were collected from the study (Foeniculum vulgare) and Harding grass are often area were borrowed from Notre Dame (ND) for dominant. identification confirmation. We collected vascular plants in the study area Bunchgrass prairie. Largely confluent with beginning in October 996 and ending in December annual grassland and shares some of the same 1 2010, with most collecting done in 2002 through species. Bunchgrass prairie is distinguished from 2007. We collected in all major habitats and covered annual grassland in that native, perennial grasses We all areas that were accessible. used Google Earth and forbs dominate, rather than introduced, (Europa Technologies Ltd, Surrey, UK) to identify annual ones. On drier sites, the most common areas that had not yet been covered or that native grass is purple needlegrass (Stipa pulchra). harbored potential unusual vegetation types. We Foothill needlegrass (S. lepida) is more common repeatedly visited collection areas over multiple on hills with fewer dry exposures. Native seasons until no new plant taxa were located. We graminoids that often occur on north-facing used Google Earth and a Garmin eTRex Summit hillsides include blue wildrye (Elymus glaucus GPS unit (Garmin International, Olathe, KS) to subsp. glaucus), squirreltail (Elymus multisetus), generate georeference data. See Appendix for the thingrass (Agrostispa/lens), and California brome location of common collecting areas. V1oucher (Bromus carinatus var. carinatus). In the western specimens were deposited in the Jepson Herbarium portion of the study area, California oatgrass (JEPS) or the California Department of Food and (Danthonia californica) and slender rush (Juncus Agriculture Herbarium (CDA). We predominantly tenuis) sometimes occur with the other grasses used Hickman (1993) and Flora of North America Common mentioned. forbs include narrow- Editorial Committee (1993+), but also used local leaved mule-ears ( Wyethia angustifolia), blue- floras such as Sharsmith (1945), Thomas (1961), eyed grass (Sisyrinchium helium), coyote-mint, Best et al. (1996), Ertter and Bowerman (2002), and gumplant (Grindelia camporum), Indian paint- We Howell et al. (2007) to identify collections. brush (Castilleja affinis subsp. affinis), and classified taxa as rare (collected or observed from summer lupine (Lupinusformosus var. formosus). three or fewer localities), uncommon (four to nine Freshwater marsh. Currently is restricted in the localities), occasional ( 10 to 20 localities), common study area to slow-moving sections of streams. (21 or more localities), or pervasive (found in most Common species include sneezeweed (Helenium localities). The actual number of locality occurrenc- puberulum), brown-headed rush (Juncus phaeoce- es is likely to be higher for most taxa, but, given the phalus var. paniculatus), mints (Mentha spp.), number of sample sites, the observed relative cattails (Typha spp.) and California bulrush. frequency of taxa is likely to remain constant with Seasonal ponds and vernal pools largely have further sampling. been eradicated from the study area, but some ditches and puddles support species often associ- Results and Discussion ated with vernal pools, such as rough-fruited We popcorn flower (Plagiohothrys trachycarpus). found 795 taxa within the study area: 13 ferns, 4 gymnosperms, 3 magnoliids, and 602 Materials and Methods eudicots. We searched the Consortium of California Collection History Herbaria (CCH) website (http://ucjeps.berkeley. edu/consortium/) for plant collections that were Unlike some nearby areas that are topographic obtained within the study area, using place names landmarks (e.g., Mt. Diablo and Mt. Tamalpais), KELCH AND MURDOCK: CARQUINEZ FLORA 2012] 53 1000 900 800 700 600 500 400 300 200 100 0 £ ^ &JO?^r& &rfS9 oS>* t$P£<$P A**£ dS^ $ •fP J* J* J* J* <f Decade Fig. 2. A histogram ofthe number ofplant collections in the Carquinez Strait Region over time. The numbers are from the Consortium of California Herbaria (http://ucjeps.berkeley.edu/consortium/). the historic plant collections from the study area collections include some plants from the Marti- are modest (Fig. 2). This emphasizes the utility of nez brackish marsh that no longer grow there, floristic studies in producing documented locality probably due to salinity shifts and habitat data even in areas, such as the study area, that are degradation. easily accessible to botanists at nearby research In the southwestern portion of the study area, institutions. Many of the earliest collections were Ivar Tidestrom was responsible for collecting a made near train stations. Martinez has the largest dozen or so specimens of common plants in the number of collections from the 19th century. area around Crockett in June 1895. In addition, These collections, though relatively few, are Harvey Monroe Hall collected some two dozen important, because they document plant species specimens between Point Richmond and Marti- that, in some cases, can no longer be found in the nez in March 1901. Mary Curran Brandegee study area (see below). Information on many of concentrated her collecting in the eastern portion these early collections is available through the of the county in Antioch. Nevertheless, she data provided by the participants of the CCH. collected a few specimens in Crockett in 1905, William Brewer was an important early collec- including flowers from an interesting population tor of California plants, being the main author of of Clarkia. Volume 1 of the botany portion of the Geological E. L. Greene, first professor of Botany at the Survey ofCalifornia (Brewer et al. 1876). Most of University of California, collected specimens in his collections in Contra Costa County were from the study area, particularly from Vallejo. The Mt. Diablo; within the study area he collected type specimens of summer lupine {Lupinus about a dozen taxa near Martinez in April of formosus Greene) and slender groundsel {Senecio 1862. Other early collections include 6-7 plants aphanactis Greene) are from Mare Island near by Carlotta Case at "Muir Station" in July of Vallejo. Greene also collected the type of = 1904. motoroil plant (Potentilla frondosa Greene The most important early collector of plants in Horkelia californica var. frondosa Greene Ertter the study area was Joseph Burtt Davy. He & Reveal) near Port Costa. Greene's successor at collected about 30 taxa in the southern part of the University of California, W. L. Jepson, grew the area (mostly in Martinez) in the late ISOO's up in eastern Solano County and concentrated and at the turn of the 20th century. These his early collecting near Vacaville (northeast of MADRONO 54 [Vol. 59 the study area). After going to Berkeley, much of phore grass (Pleuropogon californicus var. cali- his local collecting was in the Berkeley Hills and fornicus), rough-fruited popcornflower (Plagio- on Mt. Diablo, although he collected two grasses bothrys trachycarpus), and Contra Costa and a legume in Crockett in 1937. goldfields {Lasthenia conjugens) to vernally wet areas and starflower (Trientalis latifolia), red columbine {Aquilegia formosd), scarlet larkspur Local Extirpations (Delphinium nudicaule), and Wight's paintbrush Certain plants from early collections can no {Castilleja wightii) to a particularly mesic canyon longer be located within the study area. In some along the southern border of the study area. cases, the likely cause is habitat modification. Other plants, such as royal rein-orchid (Piperia Early collections from the tidal marsh at Marti- transversa) and western leatherwood (Dirca nez included species that are now found only occidentalis), are sparsely distributed throughout further east. The Delta tule pea (Lathyrusjepsonii their global range. var. jepsonii) and hedge bindweed (Calystegia Some species reach the very edge of their range sepium subsp. limnophila) are still found approx- in the study area; notable examples are typically imately 5 km east of Martinez near the eastern coastal species such as lizardtail (Eriophyllum border of the study area. Other species are no staechadifoliwn), California sheepburr (Acaena longer found within the study area, but currently pinnatifida var. californica), black sage (Salvia can be found growing together in brackish mellifera), and sea-lettuce (Dudleyafarinosa), and marshes in Suisun Bay, approximately 18 km to largely interior species such as valley loco-weed the northeast of Martinez. This includes marsh (Astragalus asymmetricus), blazing-star (Mentze- ragwort (Senecio hydrophilus), sea milkwort lia Undleyi), and three-rayed tarweed (Hemizonia (Glaux maritima), and marsh sneezeweed (Hele- lobbii). This coastal/interior gradient explains the nium bigelovii). In this case, the increased salinity limited distribution within the study area of of the marsh at Martinez may be responsible for approximately 2% of the taxa. the local extirpation of some taxa, although loss of high tidal-marsh habitat may also be a factor Endemism (H. L. Mason unpublished data). Because of the fugitive nature of some annual Because of the lack of strong edaphic discon- species, it is not possible to determine if certain tinuity (e.g., no serpentine outcrops) and paucity species no longer evident (e.g., Pentachaeta of isolated, extreme habitats (e.g., mountain alsinoides and Minuartia californica) have disap- peaks), relatively few narrow endemics occur in peared due to habitat degradation or whether the study area. Most of the endemics that do their absence is only temporary or apparent (i.e., occur grow in either tidal brackish marshes or in species may be present in the seed bank, but not heavy clay, upland soil. as reproductive adults). Nevertheless, in the case of plants adapted to specialized habitats, we may Brackish marshes. The Carquinez Strait histor- conclude that the habitat no longer exists. Vernal ically represents the major area of mixing pools were probably never common in the study between salt water from the Pacific Ocean and area, but inference from historic collections of fresh water from the Delta. Significant fresh- vernal-pool endemics proves that vernal pools water diversion from the Delta and San Joaquin occurred in Vallejo and Martinez. The current and Sacramento rivers for agriculture has led to a absence of pools in these highly developed areas significant shift in this area of mixing to the east, indicates that these respective localities for pretty causing salinity levels in tidal marshes along the downingia (Downingia pulchella) and glue-seed Carquinez Strait to increase over time (Conomos (Blennosperma nanum var. nanum) are lost 1979). Certain species of plants can tolerate forever. In addition, certain species were collected moderate but not high levels of salt. Some of repeatedly in the region in the 19th century, but these taxa are endemics in the brackish marshes have largely disappeared today; these regional of the San Francisco Bay and Delta. One such disappearances are likely due to large-scale plant is the soft birdsbeak (Chloropyron molle landscape changes. Thus, one would be unlikely subsp. molle). The C. molle complex includes C. to relocate California mustard (Caulanthus lasio- m. subsp. hispidum and C. palmatum of interior phyllus) or dobie pod (Tropidocarpum gracile) in saline marshes of the Central Valley, and C. the study area today. maritimum of coastal salt marshes. Chloropyron Of the 795 plant taxa found in the area, 463 are molle subsp. molle is found in the highest zone of native to the region. Approximately 24% (110 tidal brackish marshes in the greater San taxa) ofthese are known from only one collection Francisco Bay. All of these taxa are now rare; locality within the study area. Another 12% (43 the soft birdsbeak is federally endangered (U.S. taxa) are known from only two collection Fish and Wildlife Service 2005). It has declined localities. Of these locally rare taxa, some are due to increasing salinity, the loss of high-marsh restricted to specialized habitats, such as sema- habitat to filling, and the diking of marshes, that KELCH AND MURDOCK: CARQUINEZ FLORA 2012] 55 eliminates tidal action (Hildyard 2001). The Delta population within the study area (Ozol Rock, tule pea (Lathyrusjepsonii var. jepsonii) occurs in west of Martinez). It is a disjunct, close relative of areas with enough influx of fresh water to the yellow fairy lantern (C. amahilis) of the support tall reeds and tules. At present, this Northern Coast Ranges. The study area colony herbaceous vine grows in the study area only east of C. pulchellus is the closest population to its of the Benicia Bridge; Jepson previously collected sister species; the latter is known from Rockville km km it about 20 to the west in Crockett in 1937. (Solano County), about 25 to the north. Although not a brackish marsh endemic, Contra Costa goldfields (Lasthenia conjugens) is the most Hybridization salt-tolerant Lasthenia, sometimes occurring on CDA the edge of salt marshes (e.g., 8098, west of Hybridization in plants is often cryptic and its Suisun, Solano County). Because the habitat of origins hard to detect. Some populations of this geographically restricted species has under- putative hybrid origin (based on morphological gone massive development, most of the historic intermediacy and variability) are known from the localities have been destroyed. In the study area, study area. In the brackish marsh are clones of it is known from a single locality in a vernally wet Bolboschoenus (Scirpus spp.). Each clone differs field heavily grazed by cattle. slightly morphologically from its neighbors. These populations, named as Bolboschoenus Clay slopes. Colonies of Jepson's eryngo maritimus (L.) Palla subsp. paludosus (A. Nelson) (Eryngium jepsonii) grow on patches of dense clay on north-facing slopes along Carquinez T. Koyama, resemble intermediates between B. maritimus and B. robustus and may represent a Ridge. This species has generally been included in California eryngo (E. aristulatum); it differs in hybrid swarm. Growing in the same areas is its habitat (upland clay slopes vs. wetlands), its Grindelia stricta var. angustifolia, a taxon that is a putative hybrid between G. stricta var. an- larger fruits with large apical scales (M. Park, Univ. of California, Berkeley personal commu- gustifolia and G. camporum (Munz and Keck 1968). nication), and the bractlets that are barely longer (vs. much longer) than the flowers (Coulter and The commonest (as measured by coverage) Rose 1902). Its full range is unknown pending its native grass in the study area is a robust, rhizomatous plant generally identified as Elymus untangling from its congener, but it also occurs on clay slopes in the Mt. Diablo Area. An triticoides. Classic E. triticoides comprises smaller (60-80 cm tall), darker green plants that grow associate that often occurs with this species is clay along streams and in low-lying areas. Some mariposa-lily {Calochortus argillosus), another collections from the study area do seem to match clay endemic that has been confused with a this form (e.g., DGK04.196). Nevertheless, most similar species (in this case C. venustus). rhizomatous Elymus in the study area are larger Other endemics. Santa Cruz tarweed (Ho/ocar- (100-120 cm tall), somewhat glaucous, and grow pha macradenia), an annual in the Asteraceae, on hillsides. It is likely that these plants represent had the misfortune to be restricted to fields and introgression with the coastal E. condensatus (the low hills around San Francisco Bay and near F] hybrid is known as L. X multiflorus (Gould) & Santa Cruz. The majority of its habitat has been Barkworth R. J. Atkins). Typical E. condensa- converted to housing sites. Although never found tus has not been found in the study area, but it within the borders of the study area, it was still occurs on Brooks Island, approximately known from an adjacent region to the southwest. 10 km to the southwest. Otherwise, almost every There is still a chance that this species will be intermediate between the typical forms ofthe two found in the western portion of the study area in Elymus taxa can be seen in the western part of the grasslands subject to summer fog. study area. Western leatherwood (Dirca occidentalis) is a shrub that is known only from counties that Naturalized Plants border San Francisco Bay, where it is very sparsely distributed. Its northeastern distribu- More than a third (42%) of the species in the tional limit is within the study area in Edwards study area are introduced from outside of Canyon, above the town of Crockett. The rarity California. These 331 species range from rare to of this taxon is difficult to explain; it grows in the pervasive. The percentage of introduced plant ecotone between coastal scrub and mixed ever- taxa in the study area is higher than that for the green forest, both common plant associations in state of California as a whole (42% vs. 25%; the San Francisco Bay Area. Its restriction to Ornduff et al. 2003). This elevated number of certain watersheds may indicate that its fruits are introduced taxa may be a result of the relatively subject to limited dispersal. disturbed nature of the study area (see Pino et al. Mount Diablo fairy lantern (Calochortus pul- 2006). Of eudicots and monocots, 41% (249) and chellus) is a narrow endemic found only in the 42% (79), respectively, are adventives introduced vicinity of Mt. Diablo, with one known outlying since European colonization (denoted in the plant MADRONO 56 [Vol. 59 list by *). Non-native plants are least apparent in Although present in Vallejo since at least 1937 plant associations dominated by woody species (UC 659018), until recently, bishop's weed (Ammi and in wetlands. In upland, herb-dominated majus) has not been common in the area. It is associations, non-native species generally domi- beginning to appear along major roads and nate, often constituting over 95% of the canopy highways within the study area and has come to cover. Grassland patches dominated by native dominate long stretches of roadside to the north species do occur within the study area (e.g., Bull of the study area. It is likely that bishop's weed Valley Prairie and 5th Street Prairie) but they are will soon establish populations south ofthe strait. rare and relatively small (<0.2 hectares). Similarly, stinkwort (Dittrichia graveolens) was so Long-established weeds. Some introduced rare in California in the 1990's that it was not included in the Jepson Manual (Hickman 1993). plants seem to be nearing equilibrium where their It has since spread and it is now found in at least rate of increase in the study area is relatively low. 26 California counties. Within the study area, it Some of these plants are locally dominant under occurs in all four corners of the region. some situations and can have a profound effect Veldt grass (Ehrharta erecta) grows in dry on the plant community structure. Typical of shade; it became established in California about these taxa are annual grasses, largely from 1930 (Stebbins 1985). It often occurs in cracks in Europe, that dominate most local grasslands. pavement, and shady garden conditions may These include bromes (Bromus spp.), barleys contribute to its spread. Within the study area it {Hordeum spp.), ryegrasses (Festuca spp.), oats is known from Crockett and near Port Costa. (Arena spp.), and annual fescues (Festuca spp.). These populations, unlike populations in and Some perennial weeds can be important in around Berkeley, may represent the recent grasslands. Fennel {Foeniculum vulgare) and expansion of this species into the study area. Harding grass (Phalaris aquaticd) are non-native Gerard's rush (Juncus gerardii subsp. gerardii), perennial weeds that have invaded non-grazed a plant native to salt marshes in the eastern grasslands extensively, particularly on the north United States, forms colonies in the upper side of the Strait. Because native perennial prairie Southampton and Martinez marshes. The success taxa are lower growing, where fennel and Hard- of this species in these marshes, the only reported ing grass are dominant, most native taxa are California localities, as well as the dispersal excluded. This is a particular problem on Mare opportunities of plants in tidal marshes, indicates Island, where fennel and Harding grass are slowly that it has a high likelihood of spreading increasing at the expense of native grassland extensively within the San Francisco Bay and species. Suisun Marsh ecosystems. Perennial peppergrass (Lepidium lat(folium) forms colonies on the edges of salt and brackish Keys and Species Notes marshes. It is particularly well adapted to the high-marsh zones, and it competes for space with = = plants that are restricted to this zone, such as the A=bbreviations=: exc exc=ept; fls flowers=; federally endangered soft birdsbeak (Chloropyron fr fruit; frs f=ruits; gen g=enerally; infls = inflorescences; If leaf; lflets leaflets; lvs molle subsp. mode). = = = leaves; occ occasionally; pis plants; w/ Actively spreading weeds. Some introduced with; w/o = without. Superscripts following plants, based on past collections as well as family names indicate the number of times the current distribution, seem to be actively spread- family appears in the key. ing within the study area. Some of these taxa Voucher specimens examined are given as the have been reported from Northern California for herbarium accession number (in parenthesis) decades, but they have been rare or lacking from following localities. Localities without voucher the study area until recently. Most of these taxa specimens repesent direct observations by the can be expected to expand their range within the authors. Herbarium acronyms: JEPS = Jepson study area in the future. Oblong spurge (Euphor- Herbarium (Berkeley), CAS = California Acad- CDA = bia oblongata) is found on lightly shaded hills and emy of Sciences (San Francisco), on roadsides in the southern portion of the strait. California Department of Food and Agriculture This weedy spurge has been well established in (Sacramento), GH = Gray Herbarium (Cam- the Sierra Nevada foothills. It is of limited bridge, Massachusetts), ND-G University of occurrence along the Central Coast, and many Notre Dame (Notre Dame, Indiana), SJSU = UCD of these collections are of relatively recent dates. San Jose State University (San Jose), Within the strait, it has been present since at least (University of California (Davis), RSA = Ranch 1958 (CDA 4845). Oblong spurge may be an Santa Ana Botanic Garden (Claremont), SD = example of an introduced plant that is actively San Diego Natural History Museum (San spreading in some areas (e.g., the Central Coast) Diego), SBBG = Santa Barbara Botanic Garden but has maintained low population numbers in (Santa Barbara), and UC = University of the study area area for some time. California (Berkeley)., except for those beginning