EXOTIC PLANTS AND LAND USE: IMPACTS TO BIODIVERISTY

CEER 07/31/2014

Brian Sean Early

What are exotic, invasive, and native species?

• Exotic species introduced to a new environment and do not have evolutionary ties to that environment

• Invasive species are exotic species which cause significant harm

• Native species evolved in the respective environment.

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Impacts of Exotic and Invasive Species

1. Import plant diseases and insect pests 2. Impact agriculture 3. Impact recreation and health 4. Consume Resources and Disrupt Food Webs 5. Disrupts natural com / eco processes 6. Ultimately decrease biodiversity

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1. Imported Plant Diseases & Insect Pests • Chestnut blight • Japanese Chestnut

1876, blight 1904

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Plant Diseases:

• Dutch Elm disease 1977, 2000 trees, two weeks

Plant Pests: • Japanese Beetle (Popillia japonica) 1916

– Imported to NY in plant roots; larvae live in lawns; adults polyphagous (400 sp.)

• Emerald Ash Borer

1. Imported Plant Diseases & Insect Pests

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Insect Pests Continued

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• Emerald Ash Borer • Asian beetle • Kills all ash species • 43 sp. of N.A. insects

depend on ash trees.

• It is simply impossible to import exotic species without introducing foreign diseases and pest.

2. Exotic Species Impact Agriculture(15)

• 65% of all U.S. agriculture weeds are exotic – Note this does not include weeds of natural areas

• 1980’s $3 billion /yr chemical control • Mid 1990’s losses in agriculture yield average $4.1

billion /yr and $20 billion to U.S. economy

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3. Exotic Species Impact Recreation & Health

• Invasive plants: Phragmites, alligatorweed, water hyacinth, hydrilla, Eurasian watermilfoil – Clog water ways for fishing, hunting, and transportation – U.S. spends 100 mil/yr aquatic invasive species control(9)

– Hydrilla caused and estimated 10 mil / yr in recreational losses in just 2 FL lakes. (9)

• Poisonous or caustic to humans (9)

– Approximately half of invasive plants are poisonous – Hogweed, poison hemlock, Ricin

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4. Exotic Species Consume Resources & Disrupt Food Webs

• All life depends of energy from plants • Most exotic plants are inedible for native wildlife • Exotic plant consume resource and generally do not

contribute to the food web(12)

– Native plants provided 4 times more herbivore biomass than exotic plants

– The exotic plants supported 3.2 times fewer herbivores

– Natives supported 35 times more caterpillar biomass

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4. Exotic Species Consume Resources Disrupt Food Webs

– Genotype – Eurasian genotype introduce over

300 yr ago to N.A. – In Europe the Eurasian genotype

supports 170 insects – In N. A. the Eurasian genotype

supports 5 species – The key is leaf chemistry or

physiology is different 10

• Phragmites australis both native and invasive (12)

4. Exotic Species Consume Resources Disrupt Food Webs

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5. Exotic Species Disrupt Natural Communities & Ecological Processes

• Exotic weeds are invading approximately 700,000 ha/yr of U.S. wildlife habitat (9)

• causes localized flooding, alters habitat structure, increases evapotranspiration, cause eutrophication

– Reduced biomass native plants and wildlife – Lythrum salicaria (Purple loosestrife)

• Great Smokey Mt. NP 400 of 1,500 plants are exotic (9)

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6. Ultimately Exotic Species Decrease Biodiversity

• Approximately 17,000 native plant species in the U.S.(9)

• Over 25,000 exotic plants species in the U.S.(9)

– About 5,000 plant species have escaped cultivation

• Approximately 42% of T & E species are at risk due to invasive species(9)

• Monocultures – Ligustrum sinense decrease bee and butterfly diversity (5,6)

– 23% of all trees in the Houston area are Chinese Tallow (8)

– Houston counties 50,000-70,000 ac. of Chinese Tallow(14)

– Lake Charles, Lafayette, Mobile 10,000-25,000 ac.(14) 13

Exotic Species and Land Use • All life needs space to survive. • Habitat loss and fragmentation

is the single greatest factor causing extinction and loss of biodiversity.

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Land Use and Loss of Biodiversity

• Percent species survival corresponds to percent habitat available with a 1:1 ratio(10)

• If we consume 50% of the land in U.S. 50% of the species will become extinct.(10)

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How much land have we lost?

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How much land have we lost?

• Estimated 62,500 sq. mi. suburban lawn in U.S.(7)

• Approximately 53% loss of wetlands in the conterminous U.S.

• 70% loss of eastern forest(3)

• 98.8% loss of the tallgrass prairie (90mil. ac.)(1)

– Cajun Prairie (2.5 mil ac.) less than 0.0001% remains

• 5% conterminous U.S. remains undisturbed(10)

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Why Preserve Biodiversity?

• 1) We need biodiversity for exploitation • 2) Ethical/moral reason • 3) Biodiversity literally sustains U.S.

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Biodiversity Sustains Us • Today 81% of pop. Live in

cities/sprawling suburbs(13)

• Could N.Y. City survive on central park alone? – No it requires out side resources

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Biodiversity Sustains U.S.(12)

• Nature connects us all together. – No single species can survive alone.

• Only 1% of insects affect humans negatively – Remaining 99% pollinate plants, enrich soils, keep

other insect pop. in check, and provide a food source

• Biodiversity also supports ecosystem function = more efficient services

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Biodiversity & Jenga (4)

• The role of each block changes as the tower changes • The role of each species plays in an ecosystem is

relative to the system. • In each ecosystem, habitat fragments, parks, etc… all

species have the ability to sink or save the system

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How do we preserve biodiversity and continue to develop?

• Better land use practices = less disturbance / less habitat loss

• Less disturbance/habitat loss = less invasive sp. • Increases habitat quality/function which

supports biodiversity

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The Role of Native Plants in the Urban Landscape

• Estimated 62,500 sq. mi. of suburban lawn in U.S. (7)

• Use native plants to reclaim this habitat!

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Right plants for the right place (Habitat, Soil, and Space).

Native Plants in the Urban Landscape • Can urban plantings help save habitat and reduce

biodiversity loss? • Traffic Islands New Zealand (11)

– Meuhlenbeckia astonii (zig-zag plant) • 48 individuals in the wild

– Euphorbia glauca (sea spurge) • Threatened species

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Native Plants in the Urban Landscape

• Urban plantings help save habitat & biodiversity loss

• Coontie (Zamia pumila) plants disappearing throughout Florida(2)

– so did the species dependents (atala butterfly)

– 1965 atala butterfly was extinct – Horticulture trade saved this plant

and the atala butterfly.

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It’s Our Job to Stop Invasive Species! • Exotic and Invasive plants affect us all • Can‘t rely on government laws to stop invasive

– Inspect 1% or less

• We decide what gets planted in restoration project and how our parks, lawns, road sides and green spaces are managed.

• Our job to educate others on invasive impacts • The plant nurseries will only sell what we demand

for use on our restoration projects! 27

Design and Plant Natives

• In many cases our societies are evolving but our green space are still in the 1950’s.

• So if we Design and Plant natives landscapes we can help solve todays issues of habitat & biodiversity loss

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References 1. Carey, John. 2000. Little Habitat on the Prairie. National Wildlife Federalion. Accesed

online, June 28, 2014: http://www.nwf.org/News-and-Magazines/National-Wildlife/News-and-Views/Archives/2000/Little-Habitat-on-the-Prairie.aspx.

2. Culbert, Daniel F.2010. Florida Coonties and Attala Butterflies. University of Florida, IFAS Extension. Accessed Online, July 27, 2014. http://edis.ifas.ufl.edu/pdffiles/MG/MG34700.pdf.

3. Brown, W. P. 2006. The Community Composition and Abundance of Delaware Forest Birds. Dissertation, University of Delaware, Newark.

4. De Ruiter, P. C., V. Wolters, J. C. Moore, and K. O. Winemiller. 2005. Food web Ecology: Playing Jenga and Beyond. Science 309 (68-71).

5. Hanula, James, Scott Horn. 2011. Removing an Exotic Shrub from Riparian Forests Increases Butterfly Abundance and Diversity. Forest Ecology and Management. 262 (674-680).

6. Hanula, James, Scott Horn. 2011. Removing an Invasive Shrub (Chinese Privet) Increases Native Bee Diversity and Abundance in Riparian Forests of Southeastern United States. Insect Conservation and Diversity. 4 (275-283).

7. Milesi, C., S. W. Running, C.D. Elvodge, J. B. Dietz, B. T. Tuttle, and R. R. Nemani. 2005. Mapping and Modeling the Biogeochemical cycling of Turf Grasses in the United States. Environmental Management 36 (3): 426-438.

8. Norwak, David J., Peter D. Smith, David Hitchcock, and Michael Merritt. 2005. Houston Regional Forests. Texas Forest Service Report, September. 29

References 9. Pimentel, David, L. Lach, R. Zuniga, and D. Morrison. 1999. Environmental and

Economic Costs Associated with Non-Indigenous Species in the United States. Cornell University, College of Agriculture and Life Sciences

10. Rosenzweig, Michael L. 2003. Reconciliation Ecology and the Future of Species Diversity. FFI, Oryx. 37 (2) 194-205

11. Sawyer, John. 2005. Saving Threatened Native Plant Species in Cities-from Traffic Island to Real Islands. Greening the City, Royal New Zealand Institute of Horticulture

12. Tallamy, Douglas. 2009. Bringing Nature Home: How You Can Sustain Wildlife With Native Plants. Timber Press, Inc.

13. United States Census Bureau. 2010. Accessed online July 20, 2014: http://www.census.gov/geo/reference/ua/uafacts.html.

14. United States Department of Agriculture. USDA SRS FIA Invasive Species Map. Accessed online, May 10, 2014: http://www.invasive.org/fiamaps/index.cfm.

15. Westbrooks, R. 1998. Invasive Plants, Changing the Landscape of America: Fact book. Federal Interagency Committee for the Management of Noxious and Exotic Weeds (FICMNEW), Washington, D.C.

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Kudzu Have Any Questions?

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