World distribution of Baccharis halimifolia
Baccharis halimifolia (Asteraceae, EPPO List of IAP) originates from North America where it is known to occur in Bahamas, Cuba, Canada (Nova Scotia), and the USA (Alabama, Arkansas, Connecticut, Delaware, Florida, Georgia, Louisiana, Maryland, Massachusetts, Mississippi, New Jersey, New York, North Carolina, Oklahoma, Pennsylvania, Rhode Island, South Carolina, Texas, Virginia, West Virginia). In Canada, B. halimifolia reaches its northern limit range and it is considered as an extremely rare Atlantic coastal plain species, occurring only in Tusket River estuary and its vicinity. Official conservation programmes are being implemented in this area.
The species has been introduced into Australia, and New Zealand, where it is considered invasive. Within the EPPO region, the species is also present and invasive in Belgium, France, Italy, Georgia, Spain and the United Kingdom. A few individuals were collected in the Netherlands in 2003 in the nature reserve 'Kwade Hoek'. Mr van Valkenburg visited this nature reserve in September 2012 and could not detect B. halimifolia, as the vegetation had progressed towards shrubland dominated by Hippophae rhamnoides (Elaeagnaceae, native in the Netherlands).
An EPPO Pest Risk Analysis is currently in progress for Baccharis halimifolia.
Sources
Personal communication with Johan van Valkenburg, National Plant Protection Service of the Netherlands.
Correll DS ; Correll HB (1982) Flora of the Bahama Archipelago. Cramer J, FL-9490 Vaduz, Germany. 1692 pp.
Nova Scotia Website, Species at Risk Conservation Fund 2009 Approved Projects. http://novascotia.ca/natr/wildlife/conservationfund/2009projects.asp
USDA-ARS Website, Baccharis halimifolia.