DOCSLIB.ORG

Relationships Between Scotch Broom (Cytisus Scoparius), Soil Nutrients, and Plant Diversity in the Garry Oak Savannah Ecosystem

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Relationships Between Scotch Broom (Cytisus Scoparius), Soil Nutrients, and Plant Diversity in the Garry Oak Savannah Ecosystem Plant Ecol DOI 10.1007/s11258-009-9655-7 Relationships between Scotch broom (Cytisus scoparius), soil nutrients, and plant diversity in the Garry oak savannah ecosystem Jacqueline Shaben Æ Judith H. Myers Received: 23 May 2007 / Accepted: 14 April 2009 Ó Springer Science+Business Media B.V. 2009 Abstract Scotch broom (Cytisus scoparius), is a broom-invaded plots. Finally, in greenhouse assays leguminous shrub, native to the Mediterranean, which grass growth was not affected as a result of being has invaded most of the remaining Garry oak savan- grown with broom; however, grasses appeared to nah ecosystems in Oregon, Washington, and British produce more flowers when grown with broom. We Columbia. Here, it is considered to be a threat to the conclude that broom does not necessarily modify soil native plant community. We tested the hypothesis that nitrogen availability but may deplete soil phosphorus broom would increase available soil nitrogen by availability and that broom invasion can be associated comparing soil nutrients in contiguous broom-invaded with increase of exotic species and/or the decline of and non-invaded sites. We then looked for changes in native species. patterns of diversity in the herbaceous community that might indicate a role of Scotch broom in changing Keywords Scotch broom Á Cytisus scoparius Á conditions following its invasion. Finally we carried Garry oak savannah ecosystem Á PRSTM probes Á out greenhouse assays to test whether broom had a Soil nitrogen Á Invasive plant greater impact on the growth of a native and an introduced grass compared to that of a native shrub. Broom was associated with only a weak trend in Introduction increased soil nitrogen, but a significant decrease in soil phosphorus was observed. Patterns of plant Scotch broom (Cytisus scoparius (L.) Link), a legu- diversity differed between two sites. At one site, minous shrub native to the Mediterranean, has 60% of the plants whose abundances increased in the become an invasive plant of ecological concern in broom-invaded plots were introduced species while several areas of the world, including parts of Australia native species abundances decreased in the broom- (Downey and Smith 2000), New Zealand (Williams invaded plots compared to broom-free plots. At the 1981), and North America (Bossard and Rejmanek other site, 60% of the plants that caused the differ- 1994; Prasad 2003). Broom is well adapted to a ences between broom-invaded and un-invaded plots moderately dry, temperate climate and is intolerant of were native species that were less abundant in the shading by trees and other shrubs. Its invasive nature is attributed to prolific seed production, persistent seeds, year-round photosynthesis due to photosyn- & J. Shaben ( ) Á J. H. Myers thetic stems, production of alkaloid compounds, Department of Zoology, University of British Columbia, 6270 University Blvd, Vancouver, BC V6T 1Z4, Canada formation of dense stands, a lack of natural enemies e-mail: [email protected] in new environments, and the ability to fix nitrogen 123 Plant Ecol (Williams 1981; Wink et al. 1983; Wheeler et al. speculate that the establishment of D. glomerata is 1987; Waterhouse 1988; Prasad 2003; Downey and facilitated by increased nitrogen availability as a Smith 2000). While broom frequently invades dis- consequence of broom invasion, and that this results turbed sites in British Columbia (BC), Washington, in a decline in native plant species and a change in and Oregon, its successful invasion of intact frag- community structure. Fertilization experiments in old- ments of the Garry oak savannah ecosystem (GOSE) fields with D. glomerata by Gurevitch and Unnasch (Parker 2001), an endangered oak and grass habitat (1989) demonstrated such a change in community (COSEWIC 2000; Fuchs 2001) makes it a species of structure. particular conservation concern. The objective of this study is to determine some of Like many legumes, broom has symbiotic root- the impacts of broom on the ecology of native plants associations with nitrogen-fixing bacteria (Rhizobia of the GOSE in southern British Columbia and to sp.). For example, Fogarty and Facelli (1999) deter- contribute to the management of the small fragments mined that broom-invaded soils in forests of South of this ecosystem that remain in order to optimize - Australia had higher levels of nitrate (NO3 ) and native plant species conservation. Here, we evaluate ? ammonium (NH4 ) than did adjacent non-broom five aspects of the impacts of broom in the GOSE by soils, and they suggested that broom is probably (1) Quantifying the seasonal soil nutrient availabil- responsible for changing soil nutrient availability. The ity correlated with Scotch broom-invasion in the ability to fix atmospheric nitrogen allows broom GOSE of southern Vancouver Island. to establish in sites with nutrient-poor soils, likely (2) Comparing the level of soil nitrogen and phos- affording it a competitive growth advantage over non- phorus availability in locations with and without N-fixing plants, and thus this is cause for concern in Scotch broom. the management of GOSE. The negative effects of (3) Determining if the level of soil nitrogen avail- nitrogen-fixing shrubs on invaded plant communities ability and plant community structure are related has already been well established in other ecosystems, in these GOSE sites. such as young volcanic sites in Hawaii (Vitousek and (4) Determining if plant diversity differs between Walker 1989; Hughes and Denslow 2005), Califor- broom-invaded and un-invaded plots in the nian coastal dune ecosystems (Maron and Connors GOSE, and whether plant community differ- 1996; Pickart et al. 1998), grassland plains of southern ences are created by changes in native and exotic US and northern Mexico (Hibbard et al. 2001), and in plant abundances. the South African fynbos (Stock et al. 1995). (5) Ascertaining whether or not an exotic nitrophyl- One way in which increased soil fertility can alter lic forage grass benefits greater than a native plant community structure is by facilitating the inva- grass when grown in association with broom in sion of exotic, competitive species such as nitrophyllic greenhouse experiments. forage grasses (Vitousek and Walker 1989;Weiss 1999). These grasses are particularly good at acquiring available soil nitrogen which allows them to grow quickly and compete successfully with other plants Methods for water, light, and other nutrients (D’Antonio and Vitousek 1992). The dense, copious leaf litter produced Sites by these grasses can alter the microclimate by atten- uating sunlight, insulating the soil from temperature To determine whether Scotch broom invasion is fluctuations, and moderating soil moisture resulting in correlated with higher levels of plant-available nitro- altered decomposition rates and possibly decreased gen, we sought study sites at which broom was still seed germination of native plants (Facelli and Pickett invading a GOSE location. This proved difficult as 1991). most sites were either completely invaded by broom, In the Garry oak savannah ecosystem, Dacty- had previously been invaded, and were now managed lis glomerata (L.) is one of the most common exotic, for no broom or had no broom at all. Two locations invasive forage grasses. GOSE site managers with contiguous areas invaded and un-invaded by 123 Plant Ecol broom and with similar slope, aspect, and substra- Soil nutrient measurements tum were eventually identified in the GOSE on southern Vancouver Island: Rocky Point (48°19.5000 Soil nutrient measurements were conducted using two N, 123°32.5500 W) and Bamberton (48°34.7600 N, methods: standard extraction from soil core samples 123°31.3000 W) (Fig. 1). to obtain the background total nutrient content, and At Rocky Point, five plots were established within a ion-exchange membrane probes to obtain in situ Garry oak savannah that had been used historically by available nutrient levels. the First Nations people for harvesting camas bulbs In February 2005, 15 soil cores were taken (20 mm (Camassia quamash (Pursh) Greene) and were peri- diameter, 0–10 cm depth, including organic and odically burned. More recently, European immigrants mineral soil) from each broom and non-broom plot used the site for sheep grazing (Arthur Robinson, at both sites. These were pooled, air-dried for 72 h and personal communication, 2006). All five plots at sieved through a 2 mm sieve. Soils were then analyzed Rocky Point had negligible slope, were south-facing, for pH, % C, total Kjeldahl nitrogen (TKN), avail- and were between 50 and 80 m apart. able P, Ca and K. We calculated the carbon to nitrogen The Bamberton property was only large enough to ratio (C:N) and % organic matter (from total C 9 support three study plots. This undisturbed site 1.724). received very little human traffic. It was situated From January 22, 2005 through June 12, 2005, directly south of an abandoned cement plant, which ion-exchange membrane (Plant Root Simulator, we later discovered had an impact on soil nutrients PRSTM) probes were used to determine soil nutrient reflected in high levels of calcium. The three plots availability during the course of the growing season. were east-facing and on a steep (60%) slope. Each pair of probes consists of one anion-exchange Fig. 1 Map showing locations of the two study sites on Southern Vancouver Island. Bamberton is south of Duncan, BC, on the east side of the Malahat Highway. Rocky Point is on Department of National Defense property in Metchosin, BC 123 Plant Ecol membrane probe and one cation-exchange membrane Separate t-tests were used to compare richness of probe. Probes work by adsorbing ions as they become plant species (species number) and evenness of plant available in the soil; therefore, the unit of measure- abundances (Pielou’s J’) by treatment. ment is a rate of ion availability and is described in To ascertain which species were responsible for mass of nutrient per membrane surface area per time driving the differences seen between the broom and buried.
Load more

Recommended publications
  • Genista Monspessulana – Montpellier Broom, Cape Broom, Canary Broom
    Application for WoNS candidacy Genista monspessulana – Montpellier Broom, Cape Broom, Canary Broom Contact: Ashley Millar - (08) 9334 0312; Department of Environment and Conservation (WA) October 2010 Introduction Genista monspessulana (L.) L.A.S.Johnson (Fabaceae), also known more commonly as Montpellier Broom, Cape Broom and Canary Broom, is a woody legume weed with significant current and potential impacts on forestry production, biodiversity of natural ecosystems, grazing systems, access to amenity areas and fire risk. Infestations occur in all temperate states of Australia, with particularly severe infestations in the Adelaide Hills, southern Tasmania, central and southern Great Dividing Range of NSW, central Victoria and south west WA. G. monspessulana was ranked 37th in the initial evaluation of weeds nominated for Weeds of Natural Significance (WONS) (Thorp and Lynch 2000), with a particularly high impact score due to its formation of dense, impenetrable thickets arising from a long-lived soil seed bank (source: Henry et al . 2010). Species description: G. monspessulana is an erect, perennial slender shrub which grows up to 5-6m. It has trifoliolate petiolate leaves which are more or less glabrous. This species has yellow flowers which are produced from August to January. G. monspessulana occurs in loamy soil through to lateritic and peaty sand and is commonly found along rivers and roadsides (Parsons and Cuthbertson 2001; FLORABASE DEC 2010). G. monspessulana is native to the Mediterranean region that has become established, and is considered a persistent and deleterious plant, in several other regions of the world, including the Americas, Australia and New Zealand. It is considered deleterious because of its ability to form dense almost mono-cultural stands, which replace and suppress native flora and economically valuable timber plants (Lloyd 2000).
    [Show full text]
  • (GISD) 2021. Species Profile Cytisus Scoparius. Available F
    FULL ACCOUNT FOR: Cytisus scoparius Cytisus scoparius System: Terrestrial Kingdom Phylum Class Order Family Plantae Magnoliophyta Magnoliopsida Fabales Fabaceae Common name giesta (Portuguese), Scotch broom (English), common broom (English), Irish broom (English), broomtops (English), European broom (English), Besenginster (German), genêt à balais (French) Synonym Sarothamnus scoparius , (L.) Wimmer ex Koch Spartium scoparium , (Linn.). Genista scoparius , (Lam.). Similar species Summary The densely growing Cytisus scoparius is a shrub indigenous to Europe and northern Asia that favours temperate climates and is found in abundance on sandy pastures and heaths. It is sparingly naturalized in sandy soil in North America. It grows best in dry, sandy soils in full sunlight and can also do well on soils high in boron. Where introduced, it colonizes pastures and cultivated fields, dry scrubland and \"wasteland\", and native grasslands. Most rapid spread of the plant has occurred along waterways where the seed is distributed by water. It is also spread rapidly along roads, where the seed is distributed by passing vehicles. Wind, birds, and other animals may also transport seeds. Seed re-introduction may occur from the sheep droppings during grazing. view this species on IUCN Red List Species Description Hoshovsky (1986) reports that is a perennial shrub of the Fabaceae (Leguminosae) family. The shrubs are 1-2 metres high and deciduous. The green branches are strongly angled and appear naked or almost so. The leaves are trifoliolate with petioles 2-10mm long. The leaflets are obovate to oblanceolate, entire, strigose, and 6-12mm long. Unlike Cytisus monspessulanus (French broom) and Spartium junceum (Spanish broom), the yellow flowers of C.
    [Show full text]
  • Species: Cytisus Scoparius, C. Striatus
    Species: Cytisus scoparius, C. striatus http://www.fs.fed.us/database/feis/plants/shrub/cytspp/all.html SPECIES: Cytisus scoparius, C. striatus Table of Contents Introductory Distribution and occurrence Botanical and ecological characteristics Fire ecology Fire effects Management considerations References INTRODUCTORY AUTHORSHIP AND CITATION FEIS ABBREVIATION SYNONYMS NRCS PLANT CODE COMMON NAMES TAXONOMY LIFE FORM FEDERAL LEGAL STATUS OTHER STATUS Scotch broom Portuguese broom © Br. Alfred Brousseau, Saint Mary's © 2005 Michael L. Charters, Sierra Madre, College CA. AUTHORSHIP AND CITATION: Zouhar, Kris. 2005. Cytisus scoparius, C. striatus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/ [2007, September 24]. FEIS ABBREVIATION: CYTSCO CYTSTR CYTSPP 1 of 54 9/24/2007 4:15 PM Species: Cytisus scoparius, C. striatus http://www.fs.fed.us/database/feis/plants/shrub/cytspp/all.html SYNONYMS: None NRCS PLANT CODE [141]: CYSC4 CYST7 COMMON NAMES: Scotch broom Portuguese broom English broom scotchbroom striated broom TAXONOMY: The scientific name for Scotch broom is Cytisus scoparius (L.) Link [48,55,57,63,105,112,126,132,147,154,160] and for Portuguese broom is C. striatus (Hill) Rothm. [55,63,132]. Both are in the pea family (Fabaceae). In North America, there are 2 varieties of Scotch broom, distinguished by their flower color: C. scoparius var. scoparius and C. scoparius var. andreanus (Puiss.) Dipp. The former is the more widely distributed variety, and the latter occurs only in California [63]. This review does not distinguish between these varieties.
    [Show full text]
  • Patterns of Pollination and Seed Predation Limit Scotch Broom (Cytisus Scoparius L.) Robert Bode, Phd Saint Martin’S University Our Well-Known Nemesis
    Patterns of Pollination and Seed Predation Limit Scotch Broom (Cytisus scoparius L.) Robert Bode, PhD Saint Martin’s University Our Well-Known Nemesis • Cytisus scoparius L. • Noxious, invasive, toxic, etc. • Self-incompatible • Biocontrols introduced Self-Incompatibility • Unusual in an invasive • Goldenrod in Britain and Japan • Kudzu may evolve selfing (Steven et al 2013) • Invader in need of a pollinator Pollinator limitation • Scotch broom is pollinator limited (Parker 1997) • But it seems to be doing just fine… • Do urban structures limit pollination in broom? Pollinator selection on Floral Traits in Scotch broom • If pollinators are limiting broom, their choice should exert selective pressure • We may see pollinator choice • Footprint of evolution past Selection along a gradient • Urban patches may be distinct samples • Gradient along Martin Way • Will bees prefer certain plants? • Will flowers be different sizes? Flower size varies, but without a pattern Malo and Baonza 2002 • If selection is present, it has not led to local adaptations • Gene flow may homogenize the population 26 25 24 23 22 • Variation is higher within sites 21 20 than in Malo and Baonza’s entire 19 18 Banner Width (mm) Width Banner study! 17 16 0 5 10 15 20 25 30 Site number Selection on flowers differs between urban and rural populations Slope of the line as a selection gradient: pollination as a proxy for fitness Urban Rural Site 31 Site 1 0.9 0.6 0.8 0.5 0.7 0.6 0.4 0.5 y = -0.0537x + 1.294 y = 0.0613x - 0.734 0.3 0.4 Pollinated (Fitness) Pollinated Pollinated
    [Show full text]
  • Scotch Broom
    C Fabaceae—Pea family Cytisus scoparius (L.) Link Scotch broom Susan E. Meyer Dr. Meyer is a research ecologist at the USDA Forest Service’s Rocky Mountain Research Station, Shrub Sciences Laboratory, Provo, Utah Growth habit, occurrence, and uses. The genus indigenous species. The result is that seed production may Cytisus comprises about 80 species native to Eurasia and be severely pollinator-limited (Parker 1997). In spite of this, North Africa. Many are cultivated as ornamentals, and sever- the plants may produce a prodigious number of seeds; the al of these have become more or less naturalized in the estimated mean annual production per plant was about United States, especially in California (Munz and Keck 10,000 seeds in 2 California populations (Bossard and 1959). Scotch broom—C. scoparius (L.) Link—was planted Rejmanek 1994). Host-specific pre-dispersal seed predators extensively for erosion control during the first half of the from Europe (a seed weevil and a bruchid beetle) have been century (Gill and Pogge 1974) but is now considered a seri- introduced for biocontrol of Scotch broom in the Northwest, ous invasive weed throughout the range of its introduction in but so far these introductions have been largely ineffective, North America, Australia, and New Zealand (Bossard 1991). possibly because of asynchrony in the phenology of host It has become the dominant species on several hundred and seed predator (Bravo 1980). thousand hectares of coastal and cis-montane vegetation, Plants reach reproductive maturity at about 4 years of from Santa Barbara, California, north to British Columbia. It age (Gill and Pogge 1974).
    [Show full text]
  • Periodic Status Review for the Western Gray Squirrel
    STATE OF WASHINGTON February 2016 Periodic Status Review for the Western Gray Squirrel Gary J. Wiles Washington Department of FISH AND WILDLIFE Wildlife Program The Washington Department of Fish and Wildlife maintains a list of endangered, threatened, and sensitive species (Washington Administrative Codes 232-12-014 and 232-12-011). In 1990, the Washington Wildlife Commission adopted listing procedures developed by a group of citizens, interest groups, and state and federal agencies (Washington Administrative Code 232-12-297). The procedures include how species list- ings will be initiated, criteria for listing and delisting, a requirement for public review, the development of recovery or management plans, and the periodic review of listed species. The Washington Department of Fish and Wildlife is directed to conduct reviews of each endangered, threat- ened, or sensitive wildlife species at least every five years after the date of its listing by the Washington Fish and Wildlife Commission. In addition, as was the case with this western gray squirrel periodic status review, the Department may initiate a review of a species if a petition is received from an interested person setting forth specific evidence and scientific data to suggest that a species may be in need of reclassification. The periodic status reviews are designed to include an update of the species status report to determine whether the status of the species warrants its current listing status or deserves reclassification. The agency notifies the general public and specific parties who have expressed their interest to the Department of the periodic status review at least one year prior to the five-year period so that they may submit new scientific data to be included in the review.
    [Show full text]
  • FACTSHEET APRIL 2019 Scotch Broom Cytisus Scoparius
    Eric Coombs, Oregon Department of Agriculture, Bugwod.org FACTSHEET APRIL 2019 Scotch Broom Cytisus scoparius About Scotch Broom Native to the Mediterranean areas of Europe, Scotch broom was introduced to BC’s Vancouver Island in the mid-19th century as an ornamental plant. Its spread continued following widespread planting as a bank stabilizer during road development, and as discarded crate packing materials for gold camps along the west coast. Legal Status Invasive Plants Regulation, Forest and Range Practices Act; Community Charter, Spheres of Concurrent Jurisdiction - Environment And Wildlife Regulation. Eric Coombs, Oregon Department of Agriculture, Bugwod.org Fruits: Flat, hairy seedpods that are initially green, turn brown to black in color. Similar Species: Spanish broom (Spartium junceum), a non-native species, has flowers that’ grow at the tips of Scotch broom stems (crowning the plant), whereas Scotch broom flowers Cytisus scoparius Code = SB n = 1130 grow along stems. IAPP July 2017 Sites per 10km block squares 1-10 Ecological Characteristics 11-20 21-50 Habitat: This escaped garden ornamental invades exposed, 51-100 well-drained mineral soil and is shade-intolerant. Over 100 0 200km 400km Reproduction: Perennial species that reproduces by seed and lateral bud growth. Mature plants can produce up to 3500 pods, Distribution each containing 5–12 seeds. Currently distributed on the Pacific and Atlantic coasts of North Dispersal: As seedpods dry America. It is common west of the Coast-Cascade Mountains in they split and spiral, expelling southwest BC and is concentrated at the southern end of the contained seeds up to 5 Vancouver Island. It has also been reported on the Queen Charlotte metres.
    [Show full text]
  • Cytisus Scoparius (L.) J.H.F
    Cytisus scoparius (L.) J.H.F. Link Scotch Broom (Genista andreana, Genista scoparia, Sarothamnus scoparius, Sarothamnus vulgaris, Spartium scoparium) Other Common Names: Broomtops, Common Broom, European Broom, Irish Broom, Scottish Broom. Family: Fabaceae (Leguminosae); sometimes placed in Papilionaceae . Cold Hardiness: USDA zones 6 (5) to 7 (8). Foliage: Alternate, semi-evergreen to deciduous, trifoliate (mostly) to simple (tips of some twigs) leaves are small, ¼O to eO long, medium to dark green in color, but covered in open whitish pubescence, lending a frosted appearance to the margins; no significant fall color develops. Flower: Flowering occurs in spring from buds on old wood with one or two bright yellow :O to 1O diameter indi- vidual flowers; the back petal is the largest and is bilobed; this petal may be yellow (most common color), pink, orangish red, to red outside; flowers are numerous and very showy in bloom. Fruit: Small seeds are borne in 1½O to 2O long pea pod-like explosively dehiscent fuzzy capsules; pods mature from green to tan-brown at maturity, but are not ornamentally effective. Stem / Bark: Stems — young stems are thin, stiff and held erect in a wisp-broom fashion; young and intermediate stems are square in cross-section; new growth is covered in a sparse white pubescence which is slowly lost as the twigs mature; the bark is initially bright green, becoming mottled white and brown as twigs age; Buds — 1 1 nearly foliose with poorly formed bud scales, the tiny /32O to /16O long roundish green buds are tightly ap- pressed to the stems; Bark — bark changes as stems age from green on new twigs, mottled green and brown on older twigs, to striated green and brown on young limbs, to smooth greenish gray to brownish gray on older trunks.
    [Show full text]
  • Genista Monspessulana (L.) L
    WRITTEN FINDINGS OF THE WASHINGTON STATE NOXIOUS WEED CONTROL BOARD DRAFT August 24, 2012 Scientific name: Genista monspessulana (L.) L. A. S. Johnson Synonyms: Cytisus monspessulanus L., Cytisus monspessulanus var. umbellulatus (Webb) Briq., Teline candicans var. umbellulatus Webb & Berthel., Teline monspessulana (L.) K. Koch Common name: French broom, canary broom, cape broom, Montpellier broom, soft broom Family: Fabaceae Legal Status: Proposed Class A noxious weed Description and Variation: (Unless otherwise noted, information in this section is from DiTomaso and Healy (2007). Overall Habit: Genista monspessulana is a shrub in the Fabaceae (legume) family that typically grows less than 3 m (10 feet) tall but sometimes grows to 5 m (16 feet) tall (Baldwin et al. 2012, Bossard 2000). Plants can be evergreen or deciduous; in California G. monspessulana keeps much of its leaves in coastal areas and loses more of its leaves in inland areas (Bossard 2000). Stems are erect, typically leafy and covered in silky, silvery hairs (Baldwin et al. 2012, Stace 2010). Younger stems are green and round in cross-section and often strongly 8-10 ridged, while older stems are brown and may not have ridges. Roots: Genista monspessulana is a taprooted shrub that has fine roots associated with nitrogen-fixing bacteria. Leaves: Leaves are alternately arranged with a petiole (<5mm) and compound with 3 leaflets (Baldwin et al. 2012). Leaflets are oblong to obovate and variable in size with most 10-20 mm long, with the length generally +/- 2 times the width (Baldwin et al. 2012). The leaf’s upper and lower surface is sparsely to densely covered with appressed short, silvery hairs.
    [Show full text]
  • Scotch Broom (Cytisus Scoparius) and Soil Nitrogen: Ecological Implications
    SCOTCH BROOM (CYTISUS SCOPARIUS) AND SOIL NITROGEN: ECOLOGICAL IMPLICATIONS by Jacqueline Shaben B.Sc, University of Victoria, 1999 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE STUDIES (ZOOLOGY) THE UNIVERSITY OF BRITISH COLUMBIA October 2006 © Jacqueline Shaben, 2006 ABSTRACT Scotch broom (Cytisus scoparius), a leguminous shrub with nitrogen-fixing rhizobial root associations, is an invasive plant in the endangered Garry oak ecosystem (GOE) of Southern British Columbia. Broom frequently spreads from disturbed areas such as power line right-of-ways, and thus is a threat to native ecosystems. To unravel the ecological relationship between Cytisus scoparius and soil nitrogen, I conducted two independent studies in 2004-2005. The first study assessed broom's effect on nutrient availability and plant community composition in two Garry oak sites. The second evaluated the impact on seedling recruitment of broom following fertilization with biosolids obtained from sewage treatment. To determine if broom increased soil nitrogen availability, adjacent broom-invaded and non-invaded plots at two GOE sites (Rocky Point and Bamberton) were investigated. Here, soil-nutrient availability was compared using PRS™ ion-exchange membrane probes and concurrent plant surveys. No differences were observed in nitrogen availability between broom-present and -absent plots except for a weak trend of higher NHV" at Rocky Point. By contrast, phosphorus availability at Rocky Point was significantly lower in the broom-present plots. Plant richness was independent of broom presence, however multivariate analysis showed that species identity and abundance differed, with native species declining and introduced species increasing in the broom- invaded plots.
    [Show full text]
  • Western Gray Squirrel Recovery Plan
    STATE OF WASHINGTON November 2007 Western Gray Squirrel Recovery Plan by Mary J. Linders and Derek W. Stinson by Mary J. Linders and Derek W. Stinson Washington Department of FISH AND WILDLIFE Wildlife Program In 1990, the Washington Wildlife Commission adopted procedures for listing and de-listing species as en- dangered, threatened, or sensitive and for writing recovery and management plans for listed species (WAC 232-12-297, Appendix E). The procedures, developed by a group of citizens, interest groups, and state and federal agencies, require preparation of recovery plans for species listed as threatened or endangered. Recovery, as defined by the U.S. Fish and Wildlife Service, is the process by which the decline of an en- dangered or threatened species is arrested or reversed, and threats to its survival are neutralized, so that its long-term survival in nature can be ensured. This is the final Washington State Recovery Plan for the Western Gray Squirrel. It summarizes the historic and current distribution and abundance of western gray squirrels in Washington and describes factors af- fecting the population and its habitat. It prescribes strategies to recover the species, such as protecting the population and existing habitat, evaluating and restoring habitat, potential reintroduction of western gray squirrels into vacant habitat, and initiating research and cooperative programs. Interim target population objectives and other criteria for reclassification are identified. The draft state recovery plan for the western gray squirrel was reviewed by researchers and representatives from state, county, local, tribal, and federal agencies, and regional experts. This review was followed by a 90-day public comment period.
    [Show full text]
  • Chemical, Biochemical and Electrochemical Assays to Evaluate Phytochemicals and Antioxidant Activity of Wild Plants
    Food Chemistry 127 (2011) 1600–1608 Contents lists available at ScienceDirect Food Chemistry journal homepage: www.elsevier.com/locate/foodchem Chemical, biochemical and electrochemical assays to evaluate phytochemicals and antioxidant activity of wild plants ⇑ Lillian Barros, Luis Cabrita, Miguel Vilas Boas, Ana Maria Carvalho, Isabel C.F.R. Ferreira CIMO/Escola Superior Agrária, Instituto Politécnico de Bragança, Campus de Santa Apolónia, Apartado 1 172, 5301-855 Bragança, Portugal article info abstract Article history: Plants are a source of compounds that may be used as pharmacologically active products. Cytisus multif- Received 19 November 2010 lorus, Filipendula ulmaria and Sambucus nigra have been used as important medicinal plants in the Iberian Received in revised form 2 February 2011 Peninsula for many years, and are claimed to have various health benefits. Herein, the phytochemical Accepted 6 February 2011 composition and antioxidant activity of the mentioned wild medicinal plants were evaluated in vitro, Available online 2 March 2011 based on chemical, biochemical and electrochemical methods. F. ulmaria was found to be richest in anti- oxidant phytochemicals, such as phenolics (228 mg GAE/g DW), flavonoids (62 mg CE/g DW), ascorbic Keywords: acid (2700 lg/g DW) and tocopherols (497 lg/g DW). The antioxidant activity was found to vary in the Cytisus multiflorus order: F. ulmaria > S. nigra > C. multiflorus, irrespective of the analysis method. Electrochemical methods Filipendula ulmaria Sambucus nigra have proven to be rapid and inexpensive techniques to characterise the antioxidant activity of plant Antioxidants extracts. Phytochemicals Ó 2011 Elsevier Ltd. All rights reserved. Chromatography Electrochemistry 1. Introduction important medicinal plants and less often as food or food additives.
    [Show full text]