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SWANSON HYDROLOGY + GEOMORPHOLOGY

Appendix B. Vegetation Survey of Meeks Creek Watershed

ecological system science hydrology + geomorphology restoration engineering regulatory compliance BOTANICAL RESOURCES OF MEEKS CREEK WATERSHED

PURPOSE

The study of vegetation carried out for this project includes preparation of a map of existing vegetation communities and a description of the ecological conditions of those communities. These can be used to compare the predicted consequences of different restoration options and as a baseline map for monitoring restoration effects. In addition, this study addresses pre-settlement vegetation and ecological processes - the only available reference basis for the restoration objectives of some of the community types.

METHODS

A comprehensive search was made from available published and unpublished information on the vegetation resources in Meeks Meadow, Campground and Marina (Study Area). The literature reviewed included: Lake Tahoe Watershed Assessment (Murphy and Knopp et al. 2000), Meeks Creek and Taylor Creek Wetland Conservation Plan (WTNC 2002), Meadows in the of (Ratliff 1985), Riparian Community Type Classification of the Sierra Nevada (Potter 2003) and Status of the Sierra Nevada (SNEP 1996). Refer to the Literature Cited section for a more complete literature listing. As appropriate, information from these and other references have been incorporated into this botanical resources report.

The botanical resources of the Study Area were examined on foot during October 2003. ecologists Brian Cleary (M.S.), and Adrian Juncosa (Ph.D.) carried out the botanical fieldwork. Plant communities were identified based on field observations and analysis of vegetation signatures using color orthophotos provided by Aerial Data Inc., at a scale of 1-inch = 200 feet. Due to the onset of inclement weather, the vegetation boundaries were mapped as hand-drawn polygons in-house, then digitized into GIS using an IKONOS color satellite photo provided by the U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU). During the field survey, notes were recorded on plant communities and species composition including invasive and non-native plant species. Plant species observed were recorded and included as Attachment B-1. Additional species are likely to occur and would require further investigation during the spring and summer blooming period.

A sequence of historic aerial photographs (1940-2003) were examined in an attempt to identify vegetation changes over time as a result of natural ecological processes, such as the effect of fire on the progression of different vegetation communities leading to a climax community, known as succession, and to reveal potential anthropogenic perturbations including logging, livestock use, and recreation associated with resource acquisition in Meeks Meadow and recreational development of Meeks Bay Campground and Marina. Vegetation communities such as Mixed Conifer Forest, Montane Chaparral, and herbaceous habitats including wet and dry Montane Meadows were readily distinguishable. Unfortunately, these aerial photos could not elucidate the

B-1 ecological conditions that occurred prior to the Euro-American settlement that took place in the Lake Tahoe Basin during the mid 1800s. Thus, despite the value of historic aerial photographs, much of our understanding of ecological changes and processes is derived from knowledge of Sierra Nevada plant ecology and observations obtained from field studies rather than analysis of historic aerial photographs.

VEGETATION CLASSIFICATION FOR THE STUDY AREA

Sierra Nevada plant communities are extremely variable in size and shape. For example, riparian areas along stream banks are linear features that can vary from fractions of an acre to several acres wide, and they can contain plant communities that extend many feet in length. Conversely, a community in a meadow is a patchy feature that can occupy a fraction to several acres and have dimensions that are many feet on a side (Potter 2003).

It is recognized that hydro-geomorphic features, including banks, shores, floodplains, bars and terraces, play a significant role in determining riparian plant community composition (Warner and Hendrix et al. 1984). Similarly, herbaceous meadow communities may be classified based on various moisture regimes that largely indicate the vegetation type and dominant species. With forest communities, broader physiographic differences including slope, aspect, precipitation, temperature, and soil development govern the distribution of this vegetation type, although their shared boundaries are seldom distinct (Whitney 1979).

It is widely believed that most plant species are ordered along environmental gradients, therefore, it is important to note that overlap in species distribution is considered largely coincidental and independent, and this may create difficulties for plant ecologists attempting to classify intricate and complex vegetation communities. Smith and Houston (1989) suggest that the vast majority of spatial and temporal structure in vegetation can be attributed to competition among species for light and water, as grow larger. Nevertheless, vegetation classification is a language created to bring order out of apparent chaos (Sawyer and Keeler-Wolf 1995) and is particularly useful to develop a baseline vegetation map for analyzing restoration alternatives and long-term monitoring.

For this study, no single existing classification system fully accommodated the observed and somewhat complex vegetation community types located on site. Some of the designations used for naming the plant communities within the watershed are based in part on the U.S. Forest Service Region 5 Ecology Group using the Calveg Series Classification System (Parker and Matayas 1979). Other references, including Sawyer and Keeler-Wolf (1995), CDFG (2002), and Potter (2003), identified similar mapping units, however, these sources did not provide sufficient overlap among the vegetation types located within the Study Area. To the extent feasible, an attempt was made to divide vegetation complexes into a level of detail that was accurate enough for practical application to the present project.

B-2 In general, the dominant plant species were considered “indicator” plant species, and thus, were used to delineate the vegetation communities where necessary. However, attention was also given to the presence of non-native and native invasive plants with emphasis placed on the herbaceous wet meadow communities dominated by various hydrophytic (water-loving) graminoid (grasses and grass-like plants such as rushes and sedges) species. Typically, this wet meadow vegetation formed somewhat distinct mosaic patterns with conifer and willow communities across the Meeks Meadow landscape, although some portions of the site did not exhibit clear, identifiable vegetation boundaries. For example, numerous young lodgepole pines ( var. murrayana) appeared to be invading portions of Wet Graminoid Meadow community in mesic (i.e., seasonally not too wet or dry) areas on site. Such areas were intentionally mapped as Lodgepole Pine Forest to reflect the ecological significance of this invading species in the context of maximizing opportunities to restore wet meadow communities in Meeks Meadow. Conversely, vegetation communities such as Mixed Conifer Forest were not mapped at a level of detail based on dominant species (e.g., White-fir Forest and Jeffrey Pine Forest etc.), as this habitat is not the primary focus of the study.

FLORISTICS AND NOMENCLATURE

The majority of the species were identified using site identification, although numerous plants, particularly the graminoid species, were identified based on detailed examination with the use of a dissecting scope. The Jepson Manual (Hickman 1993) supplied and nomenclature, as well as information regarding the distribution and habitats for many of the species identified on site. Additional references included A California Flora and Supplement (Munz and Keck 1968), A Flora of Marshes of California (Mason 1969), and the Manual of Grasses of the United States (Hitchcock 1971). All plant species provided in this report, including dominant and associate species, are first introduced with the common name, followed parenthetically by the scientific name. Thereafter, only the common name is used for each plant.

PLANT SPECIES ECOLOGY

Information regarding the identification of dominant and associate plant species with respect to classifying the vegetation communities on site was based on a subjective, qualitative assessment of the relative cover and density for each species within a given area; no quantitative measurements such as transect sampling were carried out for this phase of the project. Based on the importance of attempting to predict the consequences of several alternatives for restoring Montane Riparian and Montane Wet Meadow communities in Meeks Meadow, the wetland indicator status of each plant was obtained from the 1987 Wetland Plant List, California (Reed 1988) to examine the likelihood of plants found in various soil moisture regimes with which the listed species are typically associated.

B-3 Wetland indicator species are so designated according to their frequency of occurrence in wetlands. For instance, a species with a presumed frequency of occurrence of 67% to 99% in wetlands is designated a facultative wetland indicator species. The wetland indicator groups, indicator symbol and the frequency of occurrence of species within them in wetlands are shown in Table 1.

Table 1. Wetland Indicator Status Categories for Vascular Plants INDICATOR CATEGORY SYMBOL FREQUENCY OF OCCURRENCE OBLIGATE OBL greater than 99% FACULTATIVE WETLAND FACW 67 - 99% FACULTATIVE FAC 34 - 66% FACULTATIVE UPLAND FACU 1 - 33% UPLAND UPL less than 1% *Based upon information contained in Corps of Engineers Wetlands Delineation Manual (Environmental Laboratory 1987). “NOL” = not on the list; “NI” = not an indicator.

Obligate (OBL) and facultative wetland (FACW) indicator species are hydrophytes that occur "in areas where the frequency and duration of inundation or soil saturation produce permanently or periodically saturated soils of sufficient duration to exert a controlling influence on the plant species present" (Environmental Laboratory 1987). Facultative indicator species may be considered wetland indicator species when found growing in hydric soils that experience periodic saturation.

Ecologically, each plant is a product of the conditions under which it grows and is therefore a measure of the environment (Ornduff 1974). Documenting the indicator status of each plant on site assists in the interpretation of ecological history and trends, particularly in wetland communities, in addition to ecotonal zones that transition into upland habitats. An understanding of plant distribution and moisture requirements in relation to site conditions correlates water regime, hydro-geomorphic surface, and substrate composition. In addition, most areas that are dominated by species regarded as hydrophytic (FAC, FACW, and/or OBL species) by resource agencies typically delineate as wetlands, so this approach to vegetation community mapping provides a useful initial guide to potential TRPA and other resource agency permitting requirements.

COMMUNITY TYPES

The following community types that occur within the Study Area are first arranged under broad, largely synthetic physiognomic units. For example, Lower Montane Forest communities include Mixed Conifer Forest and Lodgepole Pine Forest, and Montane Riparian community includes Mixed Riparian Scrub habitat. These community types are roughly presented from upland forests to perennial wetlands, followed by several miscellaneous land types.

Lower Montane Forest Communities ƒ Mixed Conifer Forest

B-4 ƒ Lodgepole Pine Forest

Montane Riparian Communities ƒ Mixed Riparian Scrub

Montane Herbaceous Communities ƒ Wet Graminoid Meadow ƒ Obligate Sedge Meadow ƒ Vernal Pool ƒ Dry Graminoid Meadow

Miscellaneous Land Types ƒ Aquatic Riverine ƒ Bare Ground ƒ Developed Area

COMMUNITY TYPE DESCRIPTIONS

Lower Montane Forest Communities Mixed Conifer Forest

Structure. Mixed Conifer Forest includes approximately 300 acres of forest located in Meeks Meadow, Campground and Marina (Figure B-1). The structure and composition is variable ranging from open woodland areas in the campground with 30 percent canopy closure or less to densely forested areas with 100 percent canopy cover, particularly on north-facing slopes in the southeast section of the Study Area. Scattered understory with a somewhat sparse herbaceous layer occur within the high use campground and marina areas, however, the less disturbed portions of Mixed Conifer Forest in the southern section of the Study Area support a high diversity and greater density of understory shrubs, herbaceous forbs and grasses, particularly where gaps in the forest canopy allow adequate sunlight.

Species Composition. The Mixed Conifer Forest on site supports at least five different conifer tree species, two of which dominate individually or together co-dominate, depending upon conditions such as topographic slope, aspect, substrate and other microclimatic factors. For example, white-fir (Abies concolor) is generally the dominant tree species on cool, mesic sites that occur on north- and east-facing slopes above Meeks Meadow in the southeast section of the Study Area. Jeffrey pine (Pinus jeffreyi) typically forms open stands on more xeric sites, including occasional outcroppings of granitic rock; however, this tree also regularly dominates mesic to wet areas within riparian habitat associated with Meeks Creek. In addition, Mixed Conifer Forest sites intermediate between white-fir and Jeffrey pine occur in the west and southwest sections of the Study Area. In this and other areas, sugar pine (Pinus lambertiana) and incense cedar (Calocedrus decurrens) are important associate trees,

B-5 the former preferring moist, sunny sites, and the latter, drier sites often with reduced sunlight. Although generally recognized as a Sub-alpine or Upper Montane Conifer Forest species, lodgepole pine occurs as an associate species primarily in open, disturbed stands, often along the periphery of Mixed Conifer Forest in Meeks Meadow.

Where adequate sunlight persists, Mixed Conifer Forest dominated by white-fir exhibits a high level of floristic diversity not only in trees, but also in shrubs and herbaceous species creating a somewhat lush, multi-layered appearance in comparison to areas dominated by Jeffrey pine. Dominant conifers form the top layer, or canopy. A second layer includes broadleaf trees such as Rocky Mountain maple (Acer glabrum), mountain alder (Alnus incana ssp. tenuifolia) and redoiser dogwood (Cornus sericea), as well as young conifers. Below this is the layer, which on drier sites includes species often occurring with Jeffrey pine such as greenleaf manzanita (Arctostaphylos patula), pinemat manzanita (Arctostaphylos nevadensis), and bracken fern (Pteridium aquilinum var. pubescens), and on moister sites includes Scouler’s willow (Salix scouleriana), golden chinquapin (Chrysolepis chrysophylla), Sierra gooseberry (Ribes roezlii), common cowparsnip (Heracleum lanatum), and young fir and cedar. The lowest understory layer consists of herbaceous ground cover that varies greatly in species and density according to soil moisture, available sunlight, litter depth, as well as other factors. Some of the herbaceous species identified include American trailplant (Adenocaulon bicolor), Sierra tiger lily ( parvum), rattlesnake plantain (Goodyera oblongiflora), woodland pine drops ( andromedia), bigleaf lupine (Lupinus polyphyllus), one-sided wintergreen (Orthilia secunda), Fendler’s medowrue (Thalictrum fendleri), and California brome (Bromus carinatus).

Ecological History and Trend. Examination of historic aerial photographs suggest that the majority of Mixed Conifer Forest presently dominated by Jeffrey pine on site represents a mid- to late-seral-stage (approaching climax community) colonizing forest. Jeffrey pines commonly live 300 to 400 years, and while fairly tolerant of shade when young, usually form open sunny stands when mature. In the 1940 aerial, a somewhat open stand of large, mature, Jeffrey pine trees is evident within the Meeks Bay Campground and Marina. In addition, continuous patches of Mixed Conifer Forest dominated by Jeffrey pine occur in the north and southwest sections of the Study Area. However, early photographs also reveal that much of Meeks Meadow was previously inhabited by dense, continuous stands of coniferous trees, some of which likely consisted of mature Jeffrey pine. Although based on the relatively high level of tree density throughout most of this area and the probable wet soil moisture conditions, the majority of trees at this time were probably lodgepole pine.

More recent aerial photographs reveal the continued presence of Jeffrey pine, particularly within the campground area and adjacent to the existing marina. Based on their large size (exceeding 45 inches dbh), these trees are estimated to be at least 100 years old. This evidence, in addition to the presence of many other large Jeffrey pines in the Study Area, suggests that the age class distribution throughout much of the Mixed Conifer Forest on

B-6 site conforms somewhat closely to the conditions that are believed to have occurred prior to Euro-American settlement in the Lake Tahoe Basin. The historic aerial photographs also reveal the expansion of understory vegetation within Mixed Conifer Forest, due largely to the practice of fire suppression that has taken place over the past 75 years. Modern Mixed Conifer Forests dominated by Jeffrey pine in the Lake Tahoe Basin differ from pre-settlement forests in understory tree species composition and density; they have four times the density, the importance of white-fir and incense cedar are two to three times higher, and the importance of Jeffrey pine is 50 percent less (Murphy and Knopp et al. 2000). Following the suppression of natural fires, shade-tolerant white-fir and incense cedar have proliferated, shading out many understory shrubs, as well as the sun-loving Jeffrey pine and sugar pine.

Restoration Notes. Prior to the 1900s, when public agencies began the program of fire suppression that has continued in most areas to this day, any given patch of Mixed Conifer Forest or brushland on the west slope of the Sierra could be expected to burn every three to fifteen years, the average interval being eight or nine years (Keeley and Scott et al. 1995). Occasional lightening strikes in the Lake Tahoe Basin were supplemented by fires intentionally set by Washoe Indians (WTNC 1999) to reduce understory vegetation in the forest and thereby create more favorable conditions for wildlife and understory plants, both of which were sources of food. Most of the blazes were comparatively cool groundfires that consumed underbrush but left mature trees largely unscathed. Fire suppression in concert with changing land-use practices has dramatically changed the fire regimes of the Sierra Nevada and thereby altered ecological structures and functions in Sierran plant communities, especially those influenced by frequent low- to moderate-intensity fire (SNEP 1996). Today, after years of fire suppression, many forest areas within the Lake Tahoe Basin maintain high fuel load capacities of dead wood, downed timber, deep litter and dense understory vegetation such that when a fire does occur, the result is far worse than if small periodic ground fires had been allowed to burn.

Although ecologically beneficial, the deliberate practice of prescribed low-intensity fires within Mixed Conifer Forest on site is likely not feasible due to the risk of a catastrophic conflagration associated with the in-filled residential development in Meeks Bay. In the absence of low intensity fires, it is recommended that residents are encouraged to thin and remove much of the shade-tolerant white-fir and incense cedar saplings and small trees from around their homes and property. Dead and downed trees that represent accumulated fuel should be completely removed or chipped and left on site.

Lodgepole Pine Forest

Structure. Lodgepole Pine Forest includes approximately 40 acres of primarily young sapling and small juvenile trees of fairly even height (3-6 feet) and age-class (approximately 4-10 years old), the majority of which occur on mesic sites in Meeks Meadow (Figure B-1). Within this community, lodgepole pine represents approximately 30- 60 percent of the structural cover and density (individuals per unit area) in conjunction with Wet Graminoid

B-7 Meadow community into which it has clearly invaded. The herbaceous graminoid stratum is typically present throughout, and is moderately dense at times, particularly in areas that are more open and supports fewer trees.

Species Composition. Lodgepole pine is generally the dominant species where it occurs in relatively high densities. However, the newly invaded meadow areas with small lodgepole pine trees do support a dense cover of FACW and OBL graminoid species, including tufted hairgrass (Deschampsia cespitosa), wooly sedge (Carex lanuginosa), tufted sedge (Carex lenticularis), bluejoint grass (Calamagrostis canadensis), and Baltic rush ( balticus), among others.

Ecological History and Trend. Review of the historic aerial photographs and the Meeks Bay timber harvest maps reveal that the overwhelming majority of Lodgepole Pine Forest community mapped on site consists of early-seral-stage (early successional) forest that has invaded Meeks Meadow following logging activities that occurred largely between 1987-1997. The ability of lodgepole pine to tolerate a wide range of soil moisture conditions and rapidly occupy disturbed areas previously logged or burned is largely responsible for its notable success throughout much of the Sierra (Whitney 1979). Lodgepole pine is extremely successful in meadows and other moist areas, often forming dense thickets that frequently invade meadows (Barbour and Major 1988). However, the invasion of many high Sierra meadows by lodgepole pine in recent years is a poorly understood phenomenon (Baumgartner 1975). One hypothesis is that lodgepole pine has only recently been able to grow freely in these areas, after years of effective suppression, first by Indian-caused fires and more recently by grazing of domestic sheep (Whitney 1979).

The elimination of such fire disturbances during the past century has allowed for a high level of lodgepole pine reproduction in the meadows (Vankat 1970). In addition, Leonard et al. (1968) showed that the lodgepole pine is a flood-tolerant species with remarkable control of the rate at which moisture is absorbed and transpired according to soil conditions, speeding up the process in damp soils and slowing it down on drier sites. However, sites that remain saturated throughout the growing season do not support lodgepole pine (Barbour and Major 1988).

Restoration Notes. Periodic fires, which served to keep Lodgepole Forest open, are no longer allowed to burn, preventing thinning of young growth and resulting in unnaturally dense and heavy fuel accumulation (Barbour and Major 1988). Historically, mature lodgepole pines destroyed by fire, such as those caused by lightning strikes, were quickly replaced by dense stands of seedlings, similar to what has occurred following past logging activities in Meeks Meadow. Based on the relatively small height and somewhat dense stands of young lodgepole pines, coupled with the thin bark and highly flammable tree sap, small, controlled ground fires prescribed on a rotating basis during the appropriate time of year would likely reduce significant numbers of lodgepole pines that have invaded Meeks Meadow. In the absence of physical or mechanical removal from fire

B-8 or trimming, lodgepole pine trees will continue to colonize and successfully convert much of the mesic areas of Meeks Meadow to Lodgepole Pine Forest community.

Montane Riparian Communities Mixed Riparian Scrub

Structure. Mixed Riparian Scrub community includes approximately 16.5 acres of shrub-dominated vegetation ranging from 8-15 feet in height and is associated primarily with the active channel and floodplain of Meeks Creek (Figure B-1). Structurally, the majority of this community consists of small to large patches of vegetation often forming a closed (100 percent) canopy cover that lacks an understory stratum. However, in open-canopy areas with adequate sunlight, including the outer margins of this community, a number of FACW and OBL graminoid species occur as an herbaceous layer beneath the shrub overstory.

Species Composition. Mixed Riparian Scrub community is characterized by the presence of mountain alder and Lemmon’s willow (Salix lemmonii) that dominate individually, or together co-dominate forming linear stringers of riparian vegetation along the banks of Meeks Creek and scattered patches within lowland floodplain areas of Meeks Meadow. Scouler’s willow and shining willow (Salix lucida var. lasiandra) occur as occasional associate species, the former on drier, slightly elevated sites. In some areas, other riparian shrubs, including redoiser dogwood and red elderberry, also occur as associate species.

In the presence of sunlight, the substratum may include numerous FACW and OBL graminoid and forb species such as bigleaf lupine, swordleaf rush (Juncus ensifolius), hairy willowherb (Epilobium ciliatum), meadow barley (Hordeum brachyantherum), and Fendler’s meadowrue. Mixed Riparian Scrub community intergrades with Wet Graminoid Meadow and Obligate Sedge Meadow where the overstory shrub canopy is diminished; thus, mapping of this habitat often included some overlap as a mosaic of riparian vegetation with these two herbaceous communities.

Ecological History and Trend. Based on review of the historic aerial photographs, the Mixed Riparian Scrub community appears to be largely restricted to the banks and immediate floodplain of Meeks Creek. The 1940 aerial photo reveals that the majority of area within Meeks Meadow was previously inhabited by a dense and rather continuous stand of conifer forest, likely dominated by lodgepole pine. Although small, scattered patches of Mixed Riparian Scrub vegetation undoubtedly occurred in exceedingly wet, open areas of Lodgepole Pine Forest, several historic photographs clearly reveal that the majority of Mixed Riparian Scrub that currently inhabits the meadow became established following significant logging activities that removed lodgepole pines and other conifers between 1987-1997.

The presence of mountain alder and Lemmon’s willow within the meadow may be transitional to conifer forest dominated by lodgepole pine. However, successional patterns of mountain alder are poorly understood.

B-9 Youngblood and others (1985) consider mountain alder as stable features of the landscape. Conversely, Manning and Padgett (1995) feel they are early seral, although transition to other stages may be slow. Fire may play a larger role than expected in this type of riparian scrub community (Potter 2003). Smith (1998) feels they are early seral on point bars, but more stable elsewhere. Under the current conditions, this community appears relatively established and may be competing somewhat effectively with the developing Lodgepole Pine Forest. In the absence of major disturbances, the mixed riparian scrub community in Meeks Meadow may be a stable feature on the landscape, although future plant communities are unpredictable.

Restoration Notes. Mixed Riparian Scrub community requires consistent hydrologic conditions, such as periods of prolonged soil saturation, ideally within the immediate channel or active floodplain of a creek or river drainage. Normally, the streams, which are habitat for this community type, are moderately entrenched with moderate sinuosity and moderately deep channels (Potter 2003). Generally, streambed and bank materials for this type of habitat are stable, in part due to the ability of mountain alder roots to capture soil particles in suspension. Most of the soils required for alder and willow regeneration are the result of fluvial scouring and deposition from parent materials deposited as alluvium in valley floors (Barbour and Major 1998), and organic layers are commonly absent.

Based on the regular hydrologic and fluvial geomorphic requirements that sustain and regenerate this habitat, establishment of channel-floodplain connectivity, and perhaps partial removal of invading lodgepole pines, would benefit the long-term presence of Mixed Riparian Scrub community within Meeks Creek and floodplain on site. In addition, fires that were commonly set by the Washoe Indians generally created the patchy scrub, meadow, and forest landscape similar to what exists today. Therefore, the practice of small, controlled ground fires prescribed on a rotating basis during the appropriate time of year may facilitate the long-term colonization and establishment of Mixed Riparian Scrub community by reducing competitive interactions with Lodgepole Pine Forest.

Montane Herbaceous Communities Wet Graminoid Meadow

Structure. Wet Graminoid Meadow community includes approximately 93 acres of herbaceous vegetation typically with 90-100 percent canopy cover that occurs in very large stands throughout the Study Area (Figure B- 1). Graminoid wet meadows in the Sierra Nevada are typically wetlands or semi wetlands supporting a cover of emergent hydrophytes and mesophytes of the montane and subalpine zones (Ratliff 1985). Due to the rhizomateous and fibrous root mass of most graminoid species, this community is more resistant to erosion than any other vegetation type in the Study Area dominated by herbaceous vegetation.

B-10 Species Composition. Species composition of Wet Graminoid Meadow community is dominated by perennial hydrophytic (FACW and OBL plants) rushes and sedges, such as Baltic rush, tufted sedge and wooly sedge. Additional species include Nebraska sedge (Carex nebracensis), blister sedge (Carex vesicaria), common spikerush (Eleocharis macrostachya), needle spikerush (Eleocahris acicularis), rough bluegrass (Poa trivialis), tufted hairgrass, and bluejoint grass. In addition to graminoids, herbaceous forbs were also observed in this community, particularly in drier, slightly elevated portions of Meeks Meadow, including Western aster (Aster occidentalis), Anderson’s aster (Aster alpigenus var. andersonii), California corn lily (Veratrum californicum var. californicum), northwest cinquefoil (Potentilla gracilis), yarrow (Achillea millefolium), elephant head lousewort (Pedicularis groenlandica), Rydberg’s penstemon (Penstemon rydbergii), waxy checkermallow ( glaucescens), bigleaf lupine (Lupinus polyphyllus), leathery grape fern (Botrychium multifidum), and white bog orchid (Platanthera leucostachys).

Ecological History and Trend. Review of the historic aerial photographs and the Meeks Bay timber harvest maps reveal that the majority of the large stands of Wet Graminoid Meadow vegetation on site represents an early-seral-stage (early successional) community that is present primarily as a result of logging activities that occurred between 1987-1997. For example, the 1971 aerial photograph documents that more than 75 percent of what is now Wet Graminoid Meadow habitat previously consisted of dense, continuous stands of conifer forest likely dominated by lodgepole pine. In addition, approximately 40 acres of this meadow community in Meeks Meadow supports invasive stands of young lodgepole pine trees as discussed above.

Although disturbed from historic logging, the Wet Graminoid Meadow community may floristically represent an example of typical wetland meadow vegetation that occurred throughout creek, lake and floodplain areas in the Lake Tahoe Basin since the pre-settlement era. Smith (1973) noted that many meadows in Lake Tahoe show a shift in dominance of species from wet to dry meadow type as the summer progresses, which would explain the preponderance of herbaceous forb species also identified in this community during the late October field survey.

Restoration Notes. Although meadows range from wet to dry types, as a group they occur where moisture is abundant in the upper few inches of the soil surface at least during part of the growing season, and this factor, more than any other, accounts for the persistence of meadows on sites that otherwise might be covered by forest (Whitney 1979). Conditions favorable to accumulating fine-textured materials and establishing a shallow water table are prerequisite to meadow development (Storer and Usinger 1963). In addition, fire likely played a critical role in the presence and long-term stability of Wet Graminoid Meadow community by controlling the invasion of conifer forest trees. With respect to salvage and restoration, wet meadow turf can be easily removed in small pieces from existing locations and used effectively for revegetation, as well as for erosion control purposes.

B-11 Obligate Sedge Meadow

Structure. Obligate Sedge Meadow includes approximately 4 acres of herbaceous vegetation typically with 100 percent canopy cover that occurs in numerous small and large stands throughout the Study Area (Figure B-1). This community occurs in areas where surface saturation is present throughout much of the growing season. For instance, the best example of Obligate Sedge Meadow community occurs within a seasonal pond located in the northwest section of Meeks Meadow, locally referred to as “Meeks Bog.” This depression was dry during the October field survey, exposing a dense, continuous cover sedge vegetation. Additional small patches of this community too small to map occur throughout Meeks Meadow in closed, shallow depressions and linear swales near Meeks Creek where water tables may be above ground level in places, receding only in late summer. Many of these swales showed recent signs of beaver activity (beaver slides).

Species Composition. Obligate Sedge Meadow is dominated entirely by three OBL sedge species including beaked sedge (Carex utriculata), tufted sedge and wooly sedge. In this respect, it is markedly distinct floristically from Wet Graminoid Meadow in that it is greatly reduced in plant diversity as few species can withstand the rigors of this environment.

Ecological History and Trend. Examination of the historic aerial photographs show that the majority of areas supporting Obligate Sedge Meadow, including Meeks Bog, were present as early as 1940. Thus, these photos reveal that this vegetation type likely represents a mid- to late-seral-stage herbaceous climax community that is ecologically sustained by prolonged periods of complete soil saturation, a condition that precludes invasion and establishment of lodgepole pine. Therefore, this community is largely believed to represent an unaltered native habitat derived from the post-glacial era. As noted above, beaver activity including dam building may be the most significant environmental effect that may expand, modify or reduce Obligate Sedge Meadow community, particularly in areas associated with active drainage channels.

Restoration Notes. The dominance by competitive native species which are able to persist indefinitely after disturbance suggests mid- to late-seral status for this community. The rhizomateous and fibrous root mass of these graminoid species provides excellent erosion resistance, and this type of vegetation plays a substantial role in maintaining bank stability along portions of creek and river channels. Obligate Sedge Meadow wetlands should be anticipated wherever restoration activities result in the development of soil conditions that exhibit periods of prolonged soil saturation.

Vernal Pool

Structure. Vernal Pool community includes approximately 1.25 acres of vegetation with approximately 25-50 percent herbaceous cover that occurs in a single area located in the eastern central portion of the Study Area

B-12 (Figure B-1). This community consists of a rather sparse assemblage of annual hydrophytic plants, including several endemic vernal pool species that grow in partially exposed soil conditions.

Species Composition. Vernal Pool plant species observed include wooly marbles (Psilocarphus sp.), milkwort knotweed (Polygonum polygaloides), thymeleaf sandmat (Chamaesyce serpyllifolia), and popcornflower (Plagiobothrys sp.). Complete identification of wooly marbles and popcornflower was not possible as only fragments of the floral structures were available during the October field survey. Additional hydrophytic plants identified that also occur in seasonal and perennial wetland habitats include needle spikerush, hairy purslane speedwell (Veronica peregrina ssp. xalapensis), Baltic rush, western aster, rough bentgrass (Agrostis scabra), and slenderbeak sedge (Carex athrostachya).

Ecological History and Trend. Review of the historic aerial photographs for Meeks Meadow revealed that the area currently supporting vernal pool plants also existed as an open meadow habitat during 1940. Therefore, this Vernal Pool community may represent a relict habitat present prior to the pre-settlement era.

Vernal pools consist of shallow, saucer-like depressions that are ephemerally ponded. The majority of vernal pools that remain in California (over 90 percent are lost primarily as a result of agriculture and development) occur in low-lying valley and foothill areas of the California Floristic Province. These seasonal wetlands typically form on impermeable soils such as hardpan, clay pan, or volcanic basalt. Most vernal pools are typically small in scale, averaging 5 to 7 acres (Ikdeda and Schlising et al. 1990); they tend not to occur as a single pool but as interconnected clusters of ponds. These wetlands fill with water from rain and sometimes snowmelt at higher elevations that last anywhere from a few days to a few months. The unpredictable cycling of water levels combined with the limited water sources (rain/snow) creates a distinctive habitat for plant and animal species. Based on reconnaissance-level field surveys, only a single, somewhat large vernal pool community was identified in Meeks Meadow. However, it is possible that more, undiscovered vernal pools are located on site.

Restoration Notes. Vernal pools historically were impacted by agriculture, but urbanization is increasingly a factor in their degradation. Degraded pools often receive either an excess or deficit of water, which dramatically changes the fragile ecosystem (Witham 1998). Human development has directly destroyed or indirectly disturbed the balance of nutrients in many California vernal pools (Ikdeda and Schlising et al. 1990). Human disturbances of vernal pools include agricultural practices, housing construction, road construction, water diversion, channeling of rivers, conversion of habitat for livestock grazing, and impounding for waterfowl enhancement. It is these human interactions with the landscape that have had adverse, if not destructive, effects on vernal pools.

Vernal pools represent a refuge for native plant species. In addition, vernal pools, as well as other wetlands, act as water collectors and filters, so protecting the pools from contamination and decreased efficiency is vital. Due to the high sensitivity of this delicate ecosystem on site, it is recommended that restoration planning activities

B-13 avoid, protect, and do not alter hydrologic regimes in the vicinity of the vernal pool in order to prevent direct or indirect impacts to this community.

Dry Graminoid Meadow

Structure. Dry Graminoid Meadow community includes 34 acres of herbaceous vegetation distributed in small and large patches throughout Meeks Meadow (Figure B-1). Dry Graminoid Meadow is dominated by upland (FACU and FAC) plant species. Based on the absence of available moisture during some or part of the growing season, this community supports a much lower herbaceous cover and density than the other meadow communities described above. Dry Graminoid Meadow typically occupies the elevated topographic areas in Meeks Meadow.

Species Composition. Typical dominant graminoid species in this community include California brome, Douglas’ sedge (Carex douglasii), blue wildrye (Elymus glaucus), spike trisetum (Trisetum spicatum), squirreltail (Elymus elymoides), and needlegrass (Achnatherum sp.). Numerous annual and perennial forbs occur as associate species that bloom during various times of the growing season such as Holboell’s rockcress (Arabis holboellii), waxy checker mallow (Sidalcea glaucescens), narrowleaf mountain trumpet (Collomia linearis), yarrow, gland cinquefoil (Potentilla glandulosa), naked buckwheat (Eriogonum nudum), common sheep sorrel (Rumex acetosella), Canada goldenrod (Solidago canadensis), spreading groundsmoke ( diffusum), and bracken fern.

Ecological History and Trend. Examination of the historic aerial photographs show that the majority of areas supporting Dry Graminoid Meadow community were present as early as 1940. Therefore, it is possible that frequent fire has maintained this herbaceous condition for a prolonged period of time.

Restoration Notes. Due to the highly erosive nature and fragile vegetation of this community, avoid concentrated flow patterns during the restoration planning phase so that anticipated moisture regimes do not impinge directly on Dry Graminoid Meadow community.

Miscellaneous Land Types Aquatic Riverine

Structure. Aquatic Riverine community includes approximately 6 acres of aquatic perennial stream habitat predominantly associated with the bed and banks of the Meeks Creek drainage channel (Figure B-1).

Species Composition. Aquatic Riverine habitat is largely devoid of vegetation.

B-14 Bare Ground

Structure. Bare Ground includes approximately 9 acres of land associated with the Meeks Bay Campground and Lake Tahoe beachfront area (Figure B-1).

Species Composition. Bare Ground is generally devoid of vegetation.

Developed Area

Structure. Developed Area includes approximately 12 acres of paved roads and parking lots primarily associated with the Meeks Bay Campground and Marina, as well as Highway 89 (Figure B-1). Developed Area also includes the residential development located in the east section of the Study Area in the vicinity of Meeks Bay Marina.

Species Composition. Developed Area is devoid of vegetation.

LITERATURE CITATIONS

Baumgartner, D. M. 1975. Management of Lodgepole Pine Ecosystems. Symposium Proceedings, Washington State University Cooperative Extension Service.

Barbour, M. G., and J. Major. 1988. Terrestrial Vegetation of California. California Native Plant Society, Special Publication Number 9. Sacramento, California.

CDFG (California Department of Fish & Game). 2002. List of California Terrestrial Natural Communities Recognized by the California Natural Diversity Database, May 2002 edition. California Department of Fish and Game, Wildlife and Habitat Data Analysis Branch, Sacramento, California.

Environmental Laboratory. 1987. U. S. Army Corps of Engineers Wetlands Delineation Manual. Department of the Army.

Hickman, J. C. 1993. The Jepson Manual: Higher Plants of California. University of California Press.

Hitchcock, A. S. 1971. Manual of the Grasses of the United States. Dover Publications.

Ikeda, D. H., and R. A. Schlising. 1990. Vernal Pools Plants, Their Habitat and Biology. California State University at Chico. Chico, California.

Keeley, J. E., and T. Scott. 1995. Brushfires in California: Ecology and Resource Management. International Association of Wildland Fire, 1995.

B-15 Manning, M. E., and W. G. Padgett. 1995. Riparian Community Type Classification for Humboldt and Toiyabe National Forests, Nevada and Eastern California. U.S. Department of Agriculture, Forest Service, Intermountain Region. Technical Report R4-Ecol-95-01.

Mason, H. L. 1969. A Flora of the Marshes of California. University of California Press.

Munz. P. A., and D.E. Keck. 1968. A California Flora Supplement. University California Press.

Murphy, D., and M. Knopp. 2000. Lake Tahoe Watershed Assessment: Volume 1. U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station.

Ornduff, R. 1974. Introduction to California Plant Life. Berkeley: University of California Press.

Parker, I. and W. Matayas. 1979. Calveg: a Classification of Californian Vegetation. Unpublished Map and Report. U.S. Department of Agriculture, Forest Service, Pacific Southwest Region, Ecology Group, San Francisco, California.

Potter, D. A. 2003. Riparian Community Type Classification for the West Slope Central and Southern Sierra Nevada, California. U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Ratiff, R. D. 1985. Meadows in the Sierra Nevada of California: State of Knowledge. U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station.

Reed, P. B. 1988. Wetland Plant List, California. U.S. Fish and Wildlife Service.

Sawyer, J., and T. Keeler-Wolf. 1995. A Manual of California Vegetation. California Native Plant Society. Sacramento, California.

Smith, G. L. 1973. A Flora of the Tahoe Basin and Neighboring Areas. Wasmann Journal of Biology. 31:1-231.

Smith, S. 1998. Riparian Community Type Classification for National Forests in Northeastern California. U.S. Department of Agriculture, Forest Service, Pacific Southwest Region, San Francisco, California.

Smith, T., and M. Houston. 1989. A Theory of the Spatial and Temporal Dynamics of Plant Communities. Vegetation 83:49-69.

[SNEP] Sierra Nevada Ecosystem Project. 1996. Status of the Sierra Nevada: Volume 1, Assessment Summaries and Management Strategies. Wildland Resources Center Report No. 36 University California, Davis.

Storer, T. I., and R. L. Usinger. 1963. Sierra Nevada Natural History. University of California Press, Berkeley.

B-16 Vankat, J. L. 1970. Vegetation Change in Sequoia National Park, California. Ph.D. Dissertation. University of California Davis.

Warner, R. E., and Hendrix, K. M. 1984. California Riparian Systems: Ecology, Conservation, and Productive Management. University of California Press.

Whitney, S. 1979. The Sierra Nevada: A Sierra Club Naturalist’s Guide. Sierra Club, 530 Bush Street, San Francisco, California.

Witham, C. W. 1998. Ecology, Conservation and Management of Vernal Pool Ecosystems. Proceedings from a 1996 Conference. California Native Plant Society. Sacramento, California.

[WTNC] Washoe Tribe of Nevada and California. 2002. Washoe Environmental Protection Department, Gairdnerville, Nevada.

B-17 Attachment B-1. Meeks Creek Watershed Plant List

Family Scientific Name Common Name Indicator Status*

Aceraceae Acer glabrum Maple FAC breweri Brewer's angelica NOL Heracleum lanatum Common cowparsnip FACU Perideridia parishii Parish's yampah FACW Apocynaceae Apocynum androsaemifolium Mountain dogbane NOL Asteraceae Achillea millefolium Yarrow FACU Adenocaulon bicolor American trailplant NOL Antennaria umbrinella Rosy pussytoes FACU+ Arnica chamissonis ssp. foliosa Chamisso arnica FACW Artemisia douglasiana Douglas' sagewort FACW Artemisia ludoviciana Sagewort FACU- Artemisia tridentata Big sagebrush NOL Aster alpigenus var. andersonii Anderson's aster OBL Aster occidentalis Western aster FAC Gnaphalium palustre Western marsh cudweed FACW Hieracium albiflorum White hawkweed NOL Madia bolanderi Bolander's madia NOL Psilocarphus sp. Wooly marbles NOL Senecio triangularis Arrowleaf groundsel OBL Solidago canadensis Canada goldenrod FACU Tragopogon dubius Yellow salsify NOL Wyethia mollis Wooly wyethia NOL Betulaceae Alnus incana ssp. tenuifolia Mountain alder NI Boraginaceae Plagiobothrys sp. Popcornflower OBL Brassicaesae Arabis holboellii Holboell's rockcress FACU+ Caprifoliaceae Sambucus racemosa var. microbotrys Red elderberry FACU Symphoricarpos mollis Creeping snowberry NOL Vaccinium uliginosum ssp. occidentale Western blueberry FACW+ Caryophyllaceae Stellaria longipes var. longipes Meadow starwort OBL Cornaceae Cornus sericea Redosier dogwood NOL Crassulaceae Sedum spathulifolium Yellow stonecrop NOL Cupressaceae Calocedrus decurrens Incense cedar NOL Juniperus occidentalis Western Juniper NOL Cyperaceae Carex athrostachya Slenderbeak sedge FACW Carex douglasii Douglas' sedge FACU Carex fracta Fragile sheath sedge NOL Carex lanuginosa Woolly sedge OBL Carex lenticularis Tufted sedge NOL Carex nebrascensis Nebraska sedge OBL Carex subfusca Brown sedge FAC- Carex utriculata Beaked sedge NOL Carex vesicaria Blister sedge OBL Eleocharis acicularis Needle spikerush OBL Eleocharis macrostachya Common spikerush OBL Scirpus microcarpus Panicled bulrush OBL Attachment B-1. Meeks Creek Watershed Plant List

Family Scientific Name Common Name Indicator Status*

Dennstaedtiaceae Pteridium aquilinum var. pubescens Bracken Fern FACU Equisetaceae Equisetum arvense Field horsetail FAC Arctostaphylos nevadensis Pinemat manzanita NOL Arctostaphylos patula Greenleaf manzanita NOL Ledum glandulosum Western Labrador tea OBL Orthilia secunda One-sided wintergreen FACU breweri Purple mountainheath FAC Pterospora andromedea Woodland pinedrops NOL Pyrola picta Whiteveined wintergreen NOL Sarcodes sanguinea Snowplant NOL Euphorbiaceae Chamaesyce serpyllifolia Thymeleaf sandmat NOL Fabaceae Lupinus brewerii Brewer's lupine NOL Lupinus lepidus Pacific lupine NOL Lupinus polyphyllus Bigleaf lupine FACW Trifolium longipes Longstalk clover FACW Fagaceae Quercus vaccinifolia Huckleberry oak NOL Gentianaceae Gentiana calycosa Raineer pleated gentian FACW Grossulariaceae Ribes cereum Wax Currant NI Ribes roezlii Sierra gooseberry NOL Hydrophyllaceae Phacelia sp. NOL Iridaceae Iris sp. Iris NOL Juncus balticus Baltic rush OBL Juncus chlorocephalus Greenhead rush NOL Juncus drummondii Drummond's rush FACW Juncus ensifolius Swordleaf rush FACW Juncus nevadensis Nevada rush FACW Juncus orthophyllus Straightleaf rush FACW Allium validum Pacific onion OBL Lilium parvum Sierra tiger lily OBL Smilacina racemosa Large false solomon's seal FAC Smilacina stellata Little false solomon's seal FAC Veratrum californicum var. californicum California corn lily OBL Sidalcea glaucescens Waxy checkermallow NOL Nymphaeceae Nuphar luteum ssp. polysepalum Yellow pond lily OBL Epilobium angustifolium ssp. circumvagum Fireweed FAC Epilobium ciliatum Hairy willowherb FACW Gayophytum diffusum Spreading groundsmoke NOL Ophioglossaceae Botrychium multifidum Leathery grapefern FAC Orchidaceae Goodyera oblongifolia Rattlesnake plantain NOL Scentbottle, white bog Platanthera leucostachys orchid, white flowered bog NOL Pinaceae Abies concolor White fir NOL California red fir FACU Pinus albicauis Whitebark pine NOL Pinus contorta ssp. murrayana Lodgepole pine FAC Pinus jeffreyi Jeffrey pine NOL Pinus lambertiana Sugar pine NOL Tsuga mertensiana Mountain hemlock FACU+ Attachment B-1. Meeks Creek Watershed Plant List

Family Scientific Name Common Name Indicator Status*

Plantaginaceae Plantago lanceolata Narrowleaf plantain FAC- Poaceae Achnatherum sp. Needlegrass NOL Agrostis scabra Rough bentgrass FAC Agrostis stolonifera Creeping bentgrass FACW Bromus carinatus California brome NOL Calamagrostis canadensis Bluejoint FACW+ Danthonia californica California oatgrass FACW Deschampsia cespitosa Tufted hairgrass FACW Elymus elymoides Squirreltail NOL Elymus glaucus Blue wildrye FACU Glyceria elata Tall mannagrass OBL Hordeum brachyantherum Meadow barley FACW Muhlenbergia filiformis Pullup muhly FACW Phleum alpinum Mountain timothy FACW Poa pratensis Kentucky bluegrass FACU Poa secunda One-sided bluegrass NOL Poa trivialis Rough bluegrass FACW Trisetum spicatum Spike trisetum FAC+ Polemoniaceae Collomia linearis Narrowleaf mountaintrumpet FACU Ipomopsis aggregata Scarlet gilia NOL Linanthus ciliatus Whiskerbrush NOL Phlox diffusa Spreading phlox NOL Polygonaceae Eriogonum nudum Naked buckwheat NOL Polygonum polygaloides Milkwort knotweed NI Rumex acetosella Common sheep sorrel FAC- Pteridaceae Cheilanthes gracillima Lace lipfern NOL Ranunculaceae Aconitum columbianum Monkshood FACW Aquilegia formosa Western columbine FAC Ranunculus alismifolius Alisma-leaved buttercup FACW Thalictrum fendleri Fendler's meadowrue FACU Rhamnaceae Ceanothus cordulatus Whitethorn ceanothus NOL Ceanothus velutinus Tobacco brush NOL Rosaceae Amelanchier utahensis Utah service-berry NOL Fragaria sp. Strawberry NOL Geum sp. NOL Horkelia fusca Tawny horkelia NOL Potentilla glandulosa Gland cinquefoil FAC Potentilla gracilis Northwest cinquefoil FACW Prunus emarginata Bitter cherry FACU Rosa sp. Rose NOL Rubus parviflorus Thimbleberry FAC+ Spiraea densiflora Mountain spirea NOL Rubiaceae Galium sp. Bedstraw NOL Salix eastwoodiae Mountain willow OBL Salix lemmonii Lemmon's willow OBL Salix lucida ssp. lasiandra Shining willow NI Salix scouleriana Scouler's willow FAC Scrophulariaceae Castilleja sp. Paintbrush NA Cordylanthus tenuis Slender bird's beak NOL Mimulus guttatus Seep monkeyflower OBL Mimulus primuloides Primrose monkeyflower OBL Pedicularis groenlandica Elephanthead lousewort OBL Penstemon newberryi Mountainpride penstemon NOL Penstemon rydbergii Rydberg's penstemon FAC Veronica peregrina ssp. xalapensis Hairy purslane speedwell OBL Attachment B-1. Meeks Creek Watershed Plant List

Family Scientific Name Common Name Indicator Status

Violaceae Viola glabella Pioneer violet FACW Viola lobata Moosehorn violet NOL Viscaceae Arceuthobium campylopodum Western dwarf mistletoe NOL

*Wetland Indicator Status Notes:

OBL - Obligate FACW - Facultative Wetland FAC - Facultative FACU - Facultative Upland UPL - Upland NA - not applicable for generic species NI - Not an indicator NOL - Not on list - indicates frequency toward drier end of wetland indicator category + indicates frequency toward wetter end of wetland indicator category N

LEGEND Legend Vegetation Survey Boundary VEG_TYPE LOWER MONTANE FOREST COMMUNITIESA AW Mixed Conifer Forest (301.7 TotalBG Acres) D Lodgepole Pine Forest (40.2 Total Acres)DM LP MONTANE RIPARIAN COMMUNITIES MC OSM Mixed Riparian Scrub (16.5 Total Acres)VP W MONTANE HERBACEOUS COMMUNITIES WM Wet Graminoid Meadow (92.7 Total Acres) Obligate Sedge Meadow (4.3 Total Acres)

Vernal Pool (1.2 Total Acres) Dry Graminoid Meadow (34.0 Total Acres) MISCLEANEOUS LAND TYPES Aquatic Riverine (5.8 Total Acres) Includes Meeks Creek and minor tributaries Bare Ground (8.9 Total Acres) Includes areas devoid of vegetation Developed Area (12.1 Total Acres) Includes roads and developed structures

0 500 1,000 2,000

Feet 1:12,000

SWANSON HYDROLOGY + GEOMORPHOLOGY FIGURE B-1: Vegetation map of Lower Meeks Meadow and Marina Areas. 500 Seabright Ave, Suite 202 Santa Cruz, CA 95062 PH 831.427.0288 FX 831.427.0472