Question

How will invasive plants, insects and diseases likely affect southern forests and related ecosystems in the future?

Issues

• Describe historical spread and forecast future spread of significant invasives.
• Discuss the expected consequences of the spread of important invasives for forest composition, riparian health, and dependent communities.
• What is the likelihood of effective invasives control in the future, given anticipated fragmentation, parcelization and urbanization interactions?
• What forest species are likely to be completely lost as a result of the spread of invasive pests?

Subregional Issues

• Spread of Chinese tallow tree (MAV)
• Expansion of Chinese tallow in west Gulf region (Mid South)
• Hemlock Wooly Adelgid and the loss of Eastern Hemlock (App-Cumb)
• Catastrophic losses due to sudden oak death (App-Cumb)
• Effects of oriental bittersweet and other exotics on submesic and mesic areas (App-Cumb)
• SPB epidemics spreading to new areas and species (App-Cumb )
• Invasive pathways through ports (Coastal Plain)
• Effect of invasives on forest management and on native species (Piedmont)
• Issues associated with native invasive red cedar (Mid South)

Meta Issue Managers

Paul Mistretta (USDA Forest Service, Southern Region), Forest Pathogens

Don Duerr (USDA Forest Service,Southern Region), Forest Insects

Jim Miller (Southern Research Station, USDA Forest Service) with John Coulston (USDA Forest Service, Southern Research Station) and Stephen F. Enloe (Auburn University).

Methods of Analysis

Invasive pests will be discussed divided into two categories: Native and non-native

Pests discussed will include: Diseases, insects, plants, and animals

Describe the historical spread of high threat invasive pests and forecast future spread.
If accurate and adequate historical summaries exist for pests of concern in readily accessible form, we will cite the appropriate material, and update it only as necessary. (Note: For those species previously described in the SFRA document and the data remain accurate and adequate to the present analysis, these will be referenced and only minimally repeated in the current assessment.)

For pests which do not have adequate, readily available summaries we will compile summaries using existing literature the basic species biology, host range for diseases and insects, home range for nonnative plants, and current U.S. geographic occupation. Range maps will be prepared for each pest where sufficient data are available. Existing risk maps developed by FHP and the Forest Health Technology Enterprise Team will be presented as one form of projecting future spread.

For invasive insect and diseases generalized probable scenarios will be described based on past experience with invasive pests and the individual pests will be tabulated with a rating of probable/possible outcomes of continued activity into the future.

Existing FIA occupation maps for invasive plants will be used and spread projections will be attempted using outputs from the US Forest Assessment System and/or modeling using SRS FIA forest plot and invasive plant data. Where insufficient data are available, forecasts will be based on analogous information from the pest’s behavior in its home range.

Evaluate the expected consequences of the spread of existing and potential invasive species with respect to forest productivity, composition, and biodiversity; imperilment of threatened and endangered species; watershed and soil health; carbon storage; and fire dynamics.
Where known, specific information will be given for damage caused by insects and diseases to the host(s) and to its (their) ecosystem(s), both direct and indirect effects in the short and long-term. Projections of the future will be done for each described damage scenario with identification of pests likely to be (inter)active in each scenario.

For invasive plants, descriptions will be provided on potential changes in forest succession by forest type assisted by FIA modeling and impacts to attributes will be summarized from existing literature. Accurate projections of costs of possible control/management strategies will be very difficult to make, but in cases where projections can be reliably made, they will be provided.

Discuss how effective invasive pest management programs might work in the future, given that most high threat pests are in our region to stay, while others could be prevented from entering. For each invasive species, a projection for the probability of control will be provided, based both on current and potential future methodologies, including possible biocontrol and establishment of a future dynamic equilibrium in the context of a modified ecosystem. For invasive plants, developing elements of Adaptive Collaborative Restoration programs and defensive strategies will be outlined and discussed. Potential forest management strategies for successful control of invasive pests will be documented. Where possible legislation or regulation can be imposed to aid in controlling a pest, it will be suggested as part of the analysis.

Evaluate what forest species and forest types are likely to be lost or severely damages as a result of the spread of invasive pests. Current occupation and spread projections will be used to discuss extirpation of a host species or ecosystem or the permanent alteration of its function or structure. Further discussion will explore any potential radical alteration in the affected ecosystem’s ability to support recreation, hunting, ecosystem services, or any other value-producing function will be reflected in each analysis.

Evaluate the potential for using invasive plant species for the production of bioenergy or biofuels. We will summarize the rapidly increasing global literature
on the use of invasive plants currently within the southern region and planned projects for their use.

Data and Information Sources

• EPPSI data
• FIA data
• Historical records (literature) for pest ranges and damages
• SFRA summaries
• FHTET risk mapping efforts and products
• www.invasives.org (South)
• FHM data
• Invasive species assessment "systems" such as NatureServe and ExFor
• USDA Forest Regional Task Force for the Assessment of Non-native Invasive Species of Southern Forests

Links to other parts of the Southern Forest Futures Project

• All pest analyses will use landownership forecasts from the Forecasting and Analysis Team.
• Projections from the Bioenergy Team will be used to forecast the use of invasive plants and fuels created by damaging invasive insects and diseases for bioenergy production.
• The invasive plant projections will rely on modeling assistance from the Forecasting and Analysis Team as well as SRS FIA.
• Forecasts from the Climate Change Team will be used to forecast range expansions incorporating these models and the scenarios developed for I&D damage
• Cogongrass shape files and biomass estimates will be provided to the Fire Team to explore subregional fire dynamic alterations of this highly flammable species.
• Alterations to subregional water yields by the Water Team will be explored as invasive pest infestations change structure and composition, e.g., hemlock woolly adelgid.

Products

Reports will be provided for invasive diseases, insects, plants, and animals.

Written summary of pest activity currently affecting the forest ecosystems of the South including those affecting woodlands, urban forests, and the wildland-urban interface;

Maps of current ranges of these pests; Projections of future impact of the current pests and potential future pests

Potential Cooperators

• Ron Billings, Texas Forest Service, Steve Clarke, USDA Forest Service, FHP, Lufkin, TX, Jim Meeker, USDA Forest Service, FHP, Alexandria, LA and John Nowak, USDA Forest Service, FHP, Asheville, NC (southern pine beetle)
• Rusty Rhea, USDA Forest Service, FHP, Asheville, NC (HWA and BWA)
• Steve Oak, USDA Forest Service, FHP, Asheville, NC (Sudden Oak Death)
• Dale Starkey, USDA Forest Service, FHP, Alexandria, LA (Oak wilt and Oak decline)
• Steve Fraedrich, USDA Forest Service, SRS, Athens, GA (Laurel Wilt)
• John Ghent, USDA Forest Service, FHP, Asheville, NC (gypsy moth)
• Bob Rabaglia, USDA Forest Service, FHP, Washington, DC (misc non-native bark and ambrosia beetles)