Location: Invasive Plant Research Laboratory
2011 Annual Report
This year’s (May 26, 2010 thru May 25, 2011) releases were concentrated in Wellfield and their surrounding areas based on the suggestions from the Miami-Dade Department of Environmental Resources Management (DERM). Of the total 23 sites identified as wellfields, four (Newton, West, South-west and North-west) contain substantial populations of melaleuca while remaining areas were occupied either by the agricultural fields or neighborhoods and had no detectable melaleuca infestations. Survey of melaleuca invaded Wellfields and other sites in Miami-Dade County showed varying densities of biological control insects (weevil, psyllid, cecid) and an adventive foliar rust fungus (Puccinia psidii) inciting damages to the melaleuca population trees. During this reporting period we reared in screenhouse, collected from field and made 40 releases accounting for a total of 308,094 psyllid and 4,591 weevil individuals. The four wellfields: Newton, West, South-west and North-west received 20204, 200598, 8992, and 82891 individuals, respectively. During the spring of 2011 we evaluated long-term study (15-yr) plots maintained and monitored as the part of melaleuca biocontrol impact assessment program in southeastern Florida. Data revealed continued decline of melaleuca stand density leading to the significant return of native plants such as sawgrass, dahoon holly, Guiana rapanea, wax myrtle and others; these species have dominated second canopy underneath sparsely populated melaleuca trees. There is significant reduction in the number of fruit bearing melaleuca trees due to chronic damage of new flush destined for flower production. The biological control agent production, release, and establishment activities are directly monitored by principal investigator thru regular supervision and monitoring of biocontrol insect production facility and release sites.