2013 Annual Report
1a.Objectives (from AD-416):
Culture biological control agents of melaleuca, Old-world climbing fern and air potato in the laboratory, glasshouse, screenhouse and nurseries and make repeated field release in melaleuca, Old-world climbing fern, and air potato infested areas in Miami-Dade County, assess their establishment and impact (biocontrol efficacy) on the invasive plant populations in released sites.
1b.Approach (from AD-416):
Potted invasive plants will be cultured in glasshouse, screenhouse and nurseries for use in rearing biocontrol insects. Colonies of the biocontrol insects (weevil, psyllids, stem galling flies, moth, and beetle) will be be maintained in several screenhouse and walk-in screen cages. Healthy potted individuals of invasive plants will be introduced into the cages or rearing laboratory to allow the insects to transfer, establish and multiply on the plants for 2-4 weeks. Then these plants are enclosed in psyllid proof screens, number of neonates/adults will be estimated, transported to the field, plants/plant parts are removed from the pots, and then placed in the infested stands for the insects to be transferred to the adjacent trees/vines. This general approach with appropriate modifications (for each biocontrol agents) will be used for melaleuca, Old-world climbing fern, and air potato. Establishment and their impact on release sites and other permanent plots will be monitored on .
The five-year (2009-20014) Melaleuca quinquenervia (melaleuca) biocontrol project agreement (# 58-6629-9-214) between Miami-Dade County, Department of Environmental Resources Management (DERM) and USDA-ARS, Invasive Plant Research Laboratory (IPRL) represents a part of the statewide melaleuca management efforts in Florida. Additional details for the research can be found in the report for the parent project 6629-22000-011-03R. This research directly relates to inhouse Objective 5: Release and establish the populations of released invasive plant biocontrol agents, evaluate efficacy, and corroborate environmental safety of approved agents and develop and distribute the technology to customers in order to expedite their adoption and deployment.
During the current reporting period we released 148,992 melaleuca psyllids and 2,839 melaleuca weevils in melaleuca stands at 25 locations; 1,639 Austromusotima (pale moth) and 122,217 Neomusotima (brown moth) on Lygodium microphyllum (Old World climbing fern) at three locations; and 18,907 beetles on Dioscorea bulbifera (air potato) at 9 locations in various natural and recreational areas including the Everglades National Park in Miami Dade County. During this reporting period, we have evaluated long-term field study plots of Old World climbing fern and air potato study plots in Miami Dade County established in 2011-2012. Air potato leaf beetles have established in Kendal Indian Hammock Park; they are beginning to demonstrate early visual signs of negative impact on the air potato’s vegetation smothering and vine recruiting abilities by reduced vine growth through chronic feeding by adults and larvae. The Lygodium Brown moth has successfully survived through several generations in the patches of Old World climbing fern in Amelia Earhart Park site; the fern patches in the other two sites are still being assessed and may need more releases. During this summer we will be conducting final evaluation of 16-year long permanent plots established to assess long-term biocontrol impact on melaleuca. As noted in the past progress reports, significant return of native plant species following the releases of the biocontrol agents has been noted in previously monotypic melaleuca stands in Miami Dade and other parts of the State of Florida.