Skip to main content
SpringerLink
Log in

Safe Site and Seed Limitation in Cytisus Scoparius (Scotch Broom): Invasibility, Disturbance, and the Role of Cryptogams in a Glacial Outwash Prairie

  • Published:
Biological Invasions Aims and scope Submit manuscript

Abstract

In all plant populations, establishment is controlled by two factors: the supply of propagules and their access to ‘safe sites’ for growth. An infestation of invading pest plants results in a seed-production gradient, from the edge where seeds are limiting, to the center where seeds may be in excess. Do invaded sites become ‘saturated’ with seeds? How rapidly does this occur, and how does the process depend on the availability of safe sites? Are safe sites, and consequently invasion, promoted by disturbance? I quantified the response of seedling establishment to seed input and disturbance in Cytisus scoparius (Scotch broom), an exotic shrub invading glacial outwash prairie remnants in western Washington, USA. I used disturbance treatments to investigate the role of the thick cryptogamic layer in these prairies, disturbing cryptogams by scraping or by fire. The effect of fire was partitioned into two factors: burning of the background vegetation/substrate versus breaking C. scoparius seed dormancy, by adding seeds either before or after the burn. Seed treatments ranged from 20 to 1000 seeds per m2. Both seed number and surface treatment showed significant effects on seedling density, along with a significant interaction between the two factors. Disturbance did not promote C. scoparius establishment; undisturbed plots produced more seedlings than burned or scraped plots. Within the burned plots, fire scarification appeared to increase germination but this effect was not significant. For germinated seedlings, mortality through the dry season (June–August) was not significantly different among surface treatments, nor did survivorship depend on density, with the result that initial differences in germination among the treatments persisted. The message that the undisturbed cryptogam layer facilitates C. scoparius establishment suggests that ‘ecosystem management’ strategies promoting healthy, undisturbed sites will not always be effective against invasive pest species.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Andersen AN (1989) How important is seed predation to recruitment in stable populations of long-lived perennials? Oecologia (Berlin) 81: 310-315

    Google Scholar 

  • Anderson DC,Harper KT andHolmgren RC (1982) Factors influencing development of cryptogamic soil crusts in Utah deserts. Journal of Range Management 35: 180-185

    Google Scholar 

  • Belnap J (1993) Recovery rates of cryptobiotic crusts: Inoculant use assessment methods. Great Basin Naturalist 53: 89-95

    Google Scholar 

  • Bliss LC andGold WG (1999) Vascular plant reproduction, establishment, and growth and the effects of cryptogamic crusts within a polar desert ecosystem, Devon Island, N.W.T., Canada. Canadian Journal of Botany 77: 623-636

    Google Scholar 

  • Bossard CC (1990a) Secrets of an ecological interloper: Ecological studies on Cytisus scoparius in California. PhD Thesis. University of California, Davis

    Google Scholar 

  • Bossard CC (1990b) Tracing of ant-dispersed seeds: a newtechnique. Ecology (Tempe) 71: 2370-2371

    Google Scholar 

  • Bossard CC (1991) The role of habitat disturbance, seed predation and ant dispersal on establishment of the exotic shrub Cytisus scoparius in California. American Midland Naturalist 126: 1-13

    Google Scholar 

  • Bossard CC,Randall JM andHoshovsky MC (eds) (2000) Invasive Plants of California's Wildlands. University of California Press, Berkeley

    Google Scholar 

  • Chappell CB andCrawford RC (1997) Native vegetation of the south Puget Sound prairie landscape. In: Dunn P andEwing K (eds) Ecology and Conservation of the South Puget Sound Prairie Landscape, pp 107-122. The Nature Conservancy, Seattle, Washington

    Google Scholar 

  • Crawley MJ (1990) The population dynamics of plants. Philosophical Transactions of the Royal Society of London B Biological Sciences 330: 125-140

    Google Scholar 

  • Crawley MJ (1992) Seed predators and population dynamics. In: Fenner M (ed) Seeds: The Ecology of Regeneration in Plant Communities, pp 157-191. CAB International, Wallingford, UK

    Google Scholar 

  • Cross JR (1981) The establishment of Rhododendron ponticum in the Killarny oakwoods, S.W. Ireland. Journal of Ecology 69: 807-824

    Google Scholar 

  • Downey PO (2000) Broom (Cytisus scoparius (L.) Link) and fire: Management implications. Plant Protection Quarterly 15: 178-183

    Google Scholar 

  • Downey PO andSmith JMB (2000) Demography of the invasive shrub Scotch broom (Cytisus scoparius) at Barrington Tops, New SouthWales: Insights for management. Austral Ecology 25: 477-485

    Google Scholar 

  • Dunn P andEwing K (eds) (1997) Ecology and Conservation of the South Puget Sound Prairie Landscape. The Nature Conservancy, Seattle, Washington

    Google Scholar 

  • Eldridge DJ (1993) Cryptogams, vascular plants, and soil hydrological relations: Some preliminary results from the semiarid woodlands of eastern Australia. Great Basin Naturalist 53: 48-58

    Google Scholar 

  • Eriksson O andEhrlen J (1992) Seed and Microsite Limitation of Recruitment in Plant Populations. Oecologia (Berlin) 91: 360-364

    Google Scholar 

  • Ewel JJ (1986) Invasibility: Lessons from south Florida. In: Mooney HA andDrake JA (eds) Ecology of Biological Invasions of North America and Hawaii, pp 214-249. Springer-Verlag, New York

    Google Scholar 

  • Franklin JF andDyrness CT (1988) Natural vegetation of Oregon and Washington. Oregon State University Press, Corvallis

    Google Scholar 

  • Gentle CB andDuggin JA (1997) Lantana camara L. invasions in dry rainforest-open forest ecotones: The role of disturbances associated with fire and cattle grazing. Australian Journal of Ecology 22: 298-306

    Google Scholar 

  • Gilkey HM (1957) Weeds of the Pacific Northwest. Oregon State College, Corvallis

    Google Scholar 

  • Gold WG (1998) The influence of cryptogamic crusts on the thermal environment and temperature relations of plants in a high arctic polar desert, Devon Island, N.W.T., Canada. Arctic and Alpine Research 30: 108-120

    Google Scholar 

  • Gold WG,Glew KA andDickson LG (2001) Functional influences of cryptobiotic surface crusts in an alpine tundra basin of the Olympic Mountains, Washington, USA. Northwest Science 75: 315-326

    Google Scholar 

  • Harper JL (1977) Population Biology of Plants. Academic Press, New York

    Google Scholar 

  • Harper KT andBelnap J (2001) The influence of biological soil crusts on mineral uptake by associated vascular plants. Journal of Arid Environments 47: 347-357

    Google Scholar 

  • Harper KT andMarble JR (1988) A role for nonvascular plants in management of arid and semiarid rangelands. In: Tueller PT (ed) Application of Plant Sciences to Rangeland Management and Inventory, pp 135-169. Kluwer Academic Publishers, Boston

    Google Scholar 

  • Harper KT andPendleton RL (1993) Cyanobacteria and cyanolichens: Can they enhance availability of essential minerals for higher plants? Great Basin Naturalist 53: 59-72

    Google Scholar 

  • Hartway C andSteinberg EK (1997) The influence of pocket gopher disturbance on the distribution and diversity of plants in western Washington prairies. In: Dunn P andEwing K (eds) Ecology and Conservation of the South Puget Sound Prairie Landscape, pp 131-139. The Nature Conservancy, Seattle, Washington

    Google Scholar 

  • Hobbs RJ (1989) The nature and effects of disturbance relative to invasions. In: Drake JA,Mooney HA,di Castri F et al. (eds) Biological Invasions: A Global Perspective, pp 389-405. Wiley & Sons, New York

    Google Scholar 

  • Hobbs RJ andHuenneke LF (1992) Disturbance, diversity, and invasion: Implications for conservation. Conservation Biology 6: 324-337

    Google Scholar 

  • Hobbs RJ andMooney HA (1985) Community and population dynamics of serpentine grassland annuals in relation to gopher disturbance. Oecologia (Berlin) 67: 342-351

    Google Scholar 

  • Hoffmann JH andMoran VC (1991) Biological Control of Sesbania-Punicea Fabaceae in South Africa. Agriculture Ecosystems and Environment 37: 157-174

    Google Scholar 

  • Hoshovsky M (1986) Element Stewardship Abstract for Cytisus scoparius and Cytisus monspessulanus, Scotch broom and French broom. The Nature Conservancy, Arlington, Virginia

    Google Scholar 

  • Isaacson DL (2000) Impacts of broom (Cytisus scoparius) in western North America. Plant Protection Quarterly 15: 145-148

    Google Scholar 

  • Jesson L,Kelly D andSparrow A (2000) The importance of dispersal, disturbance, and competition for exotic plant invasions in Arthur's Pass National Park, NewZealand. NewZealand Journal of Botany 38: 451-468

    Google Scholar 

  • Johansen JR,St Clair LL,Webb BL andNebeker GT (1984) Recovery patterns of cryptogamic soil crusts in desert rangelands following fire disturbance. Bryologist 87: 238-243

    Google Scholar 

  • Johansen JR,Ashley J andRayburn WR (1993) Effects of range-fire on soil algal crusts in semiarid shrub-steppe of the Lower Columbia Basin and their subsequent recovery. Great Basin Naturalist 53: 73-88

    Google Scholar 

  • King SE andGrace JB (2000) The effects of gap size and disturbance type on invasion of wet pine savanna by cogongrass, Imperata cylindrica (Poaceae). American Journal of Botany 87: 1279-1286

    Google Scholar 

  • Kotanen PM (1995) Responses of vegetation to a changing regime of disturbance: Effects of feral pigs in a Californian coastal prairie. Ecography 18: 190-198

    Google Scholar 

  • Kruckeberg AR (1991) The Natural History of Puget Sound Country. University of Washington Press, Seattle, Washington

    Google Scholar 

  • Lewontin RC (1965) Selection for colonizing ability. In: Baker HG andStebbins GL (eds) The Genetics of Colonizing Species, pp 79-94. Academic Press, New York

    Google Scholar 

  • Louda SM (1982) Distribution ecology: Variation in plant recruitment over a gradient in relation to insect seed predation. Ecological Monographs 52: 25-41

    Google Scholar 

  • Louda SM andPotvin MA (1995) Effect of inflorescence-feeding insects on the demography and lifetime fitness of a native plant. Ecology (Washington DC) 76: 229-245

    Google Scholar 

  • Louda SM,Potvin MA andCollinge SK (1990) Predispersal seed predation, postdispersal seed predation and competition in the recruitment of seedlings of a native thistle in Sandhills prairie (Nebraska, USA). American Midland Naturalist 124: 105-113

    Google Scholar 

  • Maron JL andGardner SN (2000) Consumer pressure, seed versus safe-site limitation, and plant population dynamics. Oecologia (Berlin) 124: 260-269

    Google Scholar 

  • McClintock E (1985) Status reports on invasive weeds: Brooms. Fremontia 12: 17-18

    Google Scholar 

  • Metting B (1991) Biological surface features of semiarid lands and deserts. In: Skujins J (ed) Semiarid Lands and Deserts: Soil Resource and Reclamation, pp 257-293. Marcel Dekker, New York

    Google Scholar 

  • Mobley L (1954) Scotch broom, a menace to forest, range, and agricultural land. Proceedings of the 6th Annual California Weed Conference, pp 39-42

  • Orians GH (1986) Site characteristics favoring invasions. In: Mooney HA andDrake JA (eds) Ecology of Biological Invasions of North America and Hawaii, pp 133-148. Springer-Verlag, New York

    Google Scholar 

  • Parendes LA andJones JA (2000) Role of light availability and dispersal in exotic plant invasion along roads and streams in the H.J. Andrews Experimental Forest, Oregon. Conservation Biology 14: 64-75

    Google Scholar 

  • Parker IM (1996) Ecological factors affecting rates of population growth and spread in Cytisus scoparius, an invasive exotic shrub. PhD Thesis. University of Washington

  • Parker IM (2000) Invasion dynamics of Cytisus scoparius: A matrix model approach. Ecological Applications 10: 726-743

    Google Scholar 

  • Parker IM,Mertens SK andSchemske DW (1993) Distribution of seven native and two exotic plants in a tallgrass prairie in southeastern Wisconsin: The importance of human disturbance. The American Midland Naturalist 130: 43-55

    Google Scholar 

  • Paynter Q,Fowler SV,Memmott J,Shaw RH andSheppard AW (2000) Determinants of broom (Cytisus scoparius (L.) Link) abundance in Europe. Plant Protection Quarterly 15: 149-155

    Google Scholar 

  • Paynter Q,Fowler SV,Memmott J andSheppard AW (1998) Factors affecting the establishment of Cytisus scoparius in southern France: Implications for managing both native and exotic populations. Journal of Applied Ecology 35: 582-595

    Google Scholar 

  • Rees M andPaynter Q (1997) Biological control of Scotch broom: Modelling the determinants of abundance and the potential impact of introduced insect herbivores. Journal of Applied Ecology 34: 1203-1221

    Google Scholar 

  • Reifner RE andBowler PA (1995) Cushion-like fruticose lichens as Dudleya seed traps and nurseries in coastal communities. Madroño 42: 81-82

    Google Scholar 

  • Sheppard A,Hodge P andPaynter Q (2000) Factors affecting broom regeneration in Australia and their management implications. Plant Protection Quarterly 15: 156-161

    Google Scholar 

  • Snedecor GW andCochran WG (1989) Statistical Methods. Iowa State University Press, Aimes

    Google Scholar 

  • St Clair LL,Webb BL,Johansen JR andBebeker GT (1984) Cryptogamic soil crusts: Enhancement of seedling establishment in disturbed and undisturbed areas. Reclamation and Revegetation Research 3: 129-136

    Google Scholar 

  • Tveten R (1997) Fire effects on prairie vegetation, Fort Lewis, Washington. In: Dunn P andEwing K (eds) Ecology and Conservation of the South Puget Sound Prairie Landscape, pp 123-130. The Nature Conservancy, Seattle, Washington

    Google Scholar 

  • Tveten RK andFonda RW (1999) Fire effects on prairies and oak woodlands on Fort Lewis, Washington. Northwest Science 73: 145-158

    Google Scholar 

  • US Army Corps of Engineers (1994) Final Environmental Impact Statement: Stationing of Mechanized or Armored Combat Forces at Fort Lewis, Washington. Fort Lewis, Washington, US Department of the Army

    Google Scholar 

  • Watts SE (1998) Short-term influence of tank tracks on vegetation and microphytic crusts in shrubsteppe habitat. Environmental Management 22: 611-616

    Google Scholar 

  • Youngman BJ (1951) Germination of old seeds. Kew Bulletin 23: 423-426

    Google Scholar 

Download references

Author information

Author notes

  1. Ingrid M. Parker

    Present address: Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, 95064, USA (e-mail

Authors and Affiliations

  1. Department of Botany, University of Washington, Seattle, WA, USA

    Ingrid M. Parker

Authors
  1. Ingrid M. Parker
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Parker, I.M. Safe Site and Seed Limitation in Cytisus Scoparius (Scotch Broom): Invasibility, Disturbance, and the Role of Cryptogams in a Glacial Outwash Prairie. Biological Invasions 3, 323–332 (2001). https://doi.org/10.1023/A:1015855515361

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/A:1015855515361

Search

Navigation