Qinfeng GuoUSDA FS Forest Threat Assessment Center, Asheville

Studies on Invasive Species in the United States

The Problem: Numbers & Locations:

• > 4,000 introduced plant species

• ≈ $137 billions/yr loss in the US alone

• Most of them are distributed in the (south)east and west coast

Kudzu (Pueraria lobota) in SE U.S.

Leafy Spurge (Ehphorbia esula) in ND

Conclusions

• Native-exotic ranges are correlated (+): species with larger native ranges would also have larger exotic ranges!

Implications

• Current practice in counting exotics and public perception (all species introduced by human are exotics to the area – not just from foreign sources).

• Policy/management – reduce all species introduction as much as possible, especially when potential ricks have not been assessed

• Distinction between exotics and “invasives”

Logit suitability

most unsuitableslightly unsuitableslightly suitablemost suitable

specimen locations in suitability classes

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+ maxtmp - maxtmp2 + precip + precip2

+ mintmp - mintmp2 + agurb - agurb2

(Albright, Chen, Chen & Guo. 2010. Biol. Invas.)

Tree-of-heaven, Ailanthus altissima

http://worldatlas.com/

The challenges & opportunities: 2 issues

• By improving understanding of how invasives spread, managers can more effectively slow their spread, predict when and where ecological effects are likely to occur, and when and where mitigation efforts may be warranted.

• Understanding the factors that contribute to habitat invasibilty allows for more effective control and management of invasive species.

How should we respond?

• Only about 10% are actually invasive but they cause huge ecological and economic damages

• Make good use of them (e.g., biofuels, food, medicine, erosion control, …)

• Species ranking system (national/regional)• Early warning systems (e.g., EFETAC/Brown Univ.)• Effective prevention/control methods

Unique features in our research

1. Large-scale – nationwide (eastern/SE focus)2. Multidisciplinary (field, RS/GIS, modeling, …)3. Native populations and habitats

4. Collaborative (both within and outside)

UNCA-National Environmental Modeling and Analysis Center (NEMAC); Brown University, NCSU, Illinois State Museum; University of Missouri; U.S. Geological Survey-NPWRC & EROS Data Center (EDC); BLM, NPS, FWS, South Florida Water Management District; Chinese Academy of Sciences; University of California-Berkeley; Taiwan National University; University of Georgia; and other USDA Forest Service units such as FIA, Canadian Forest Service, Appalachian Trail Park Office; and Appalachian Trail Conservancy, Equinox Environmental Consultation and Design, Inc., International Union of Forest Research Organizations, …..

24 reports/publications in 2009 >10 presentation (e.g., meetings) in 2009

More info at: “http://www.forestthreats.org/”

Collaborators