Détails de cette espèce dans Florida Everglades Statut: Exotique
Statut d'envahissement: Envahissant
Occurrence: Établi(e)
Source: Mazzotti et al. 1997 Date d'introduction:
Mode d'Introduction: Notes sur l'espèce pour cette localité:
Notes sur la gestion de l'espèce dans cette localité:
The Everglades could be completely overwhelmed by melaleuca in less than 100 years if it is not kept under control (DiStefano & Fisher 1983, in Laroche 1998). Although melaleuca is a difficult species to eradicate, district, government and private group efforts are containing its spread within the Everglades Water Conservation Areas (WCAs) and the marsh of Lake Okeechobee (Laroche 1998). Melaleuca has been completely cleared from WCA-2A, -3B, and -3A, south of Alligator Alley (Laroche 1998). These areas are now under "maintenance control" (maintenance control means applying management techniques on a continuous basis to keep an invasive plant population at its lowest feasible level) (Laroche 1998). Current estimates place the infestation level at less than 400 000 hectares.
The strategy for managing melaleuca is modified to improve efficacy and cost effectiveness. The frill and girdle method, in which the bark around the circumference of each tree is completely removed to expose the cambium for application of the herbicide solution, is the primary tool used in the least infested areas (Laroche 1998). Aerial application is the most economical method for large melaleuca monocultures (Laroche 1998).
A major effort is now underway to modify the hydrology of southern Florida so as to restore some semblance of the structure and function of the original wetland systems (Ogden 2005, in Center et al 2006). This restoration effort, which focuses upon managing water, may be thwarted by the encroachment of non-indigenous plants, particularly melaleuca, into native communities (Ferriter et al., 2005, in Center et al 2006). Recovery of these systems will therefore require management of these species as well as rejuvenation of historic water flow patterns (Davis and Ogden 1994, in Center et al 2006).
A multi-agency task force comprised of scientists and resource managers organised by the Florida Exotic Pest Plant Council (EPPC) designed the Melaleuca Management Plan for Florida (Laroche 1994) - a synthesis of years of research and practical experience in melaleuca biology and management. No other invasive exotic has such a clearly articulated management plan as M. quinquenervia (Mazzotti et al. 1997). Some of the main objectives are to coordinate with and support the goals of the south Florida Ecosystem Task Force to protect the integrity of Florida's natural ecosystems from the biological degradation caused by the invasion of melaleuca (Laroche 1999). As a result of the implementation of the Melaleuca Plan almost 100 000 acres of natural area have been cleared of melaleuca (Laroche 1999). Unfortunately, an almost equal expansion of melaleuca on privately held lands where no control activities have occurred has resulted in no net loss of acreage of melaleuca (Laroche 1999). Please see the updated Melaleuca Management Plan (1999). Impacts:
Altération d'habitat: Melaleuca has altered thousands of areas of the Everglades by replacing native tree islands, sawgrass marshes, mesic prairies and aquatic sloughs (Laroche 1999). For example, the presence of melaleuca in fire-maintained sawgrass communities can promote conversion of these habitats to melaleuca forest. Everglades marshlands are comprised of fire-maintained communities of mostly sawgrass prairies. Natural fires periodically eliminate the native, fire-intolerant hardwoods that would otherwise colonise this habitat. However, because melaleuca is so well-adapted to fire it can persist and even thrive in this environment, eventually shading out the herbaceous community and transforming the site into a melaleuca forest (Turner et al. 1998, in Munger 2005).
Menace pour les espèces en danger: This unique area has produced approximately 65 endemic plant taxa, many of which are threatened due to habitat diminishment (Turner et al. 1998, in Munger 2005). Dernière mise à jour: 11/12/2009 3:13:54 p.m.
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