Study Title: Collection of Information on the Old World Climbing Fern for Use in a Model for Control of this Invading Vine
Study Start Date: 09/01/2002 Study End Date: 08/31/2005
Web Sites: ATLSS.ORG
Location: Arthur R. Marshall Loxahatchee National Wildlife Reserve
Funding Source: USGS Federal-State Partnership Funds
Principal Investigators: Donald L. DeAngelis. Phone 305-284-1690, U.S. Geological Survey, at Dept of Biology, University of Miami, Coral Gables, FL 33124. ddeangelis@umiami.ir.miami.edu and Laura A. Brandt, A.R.M. Loxahatchee NWR, 10216 Lee Road, Boynton Beach, FL 33437 561/735-6000
Study Personnel: Erynn Call
Other Supporting Organizations: USGS/BRD, NPS, ACE, EPA
Associated Projects: Related to ATLSS Program

Overview & Objectives: Lygodium microphyllum (Old World climbing fern) is an aggressive and destructive EPPC category I invasive plant. It has spread, unabated, across the South Florida landscape compromising and destroying a plethora of habitats along the way. It is especially destructive to tree islands in the Greater Everglades. Lygodium's ability to spread rapidly and over a long range is a function of its reproductive structures, small spores that can be carried great distance by air currents. While one study has addressed the seasonality of Lygodium spore production, no one has examined the range of spore dispersal. There is a need to know the distribution of Old World climbing fern (a category I invasive exotic) on the Arthur R. Marshall Loxahatchee National Wildlife Refuge (ARMLNWR) and throughout South Florida, what factors affect its spread, and the most effective strategies for its control. This study has been designed to collect information on the Old World climbing fern in the Loxahatchee NWR: "Current distribution and control of the invasive Old World climbing fern on the ARMLNWR and in the South Florida ecosystem." The results of this study will provide core information needed for the control of Old World climbing fern on the refuge and throughout the South Florida Ecosystem.

Status: During the first year of this study, mapping of Lygodium in ARMLNWR was performed. Studies on the dispersal of spores between tree islands in ARMLNWR was started in year 1 and continued into year two. The methodology employed two spore traps that could record spore deposition at one point due to dispersal from sites already occupied by Lygodium.

Recent Products: During the past year, studies on the ability of Lygodium to germinate under different conditions have been performed. Reports are due soon. In addition, under different funding, but coordinated with this project, a spatial model of Lygodium has been developed and parameterized. The model allows management policies for the control of the fern to be simulated.

Planned Products: The final phase of this project will be the development of a User Interface for the demographic model for the spread and control of Lygodium.

Specific Relevance to Information Needs Identified in DOI's Science Plan in Support of Ecosystem Restoration, Preservation, and Protection in South Florida (DOI's Everglades Science Plan) [See Plan on SOFIA's Web site: http://sofia.usgs.gov/publications/reports/doi-science-plan/]: This project is explicitly designed to address the needs of Invasive Exotic Plant Management on the Arthur R. Marshall Loxahatchee National Wildlife Refuge (page 120 of Science Plan).

Key Findings:

1. Mapping of distribution of Lygodium in Arthur R. Marshall Loxahatchee National Wildlife Refuge
2. Estimation of spread of spores from Lygodium as a function of distance from source.
3. Determination of germination success of Lygodium in different soil, water, and detrital media
4. Development of a demographic model of Lygodium that can be used by managers to aid in control.