Principal source:
Compiler: IUCN SSC Invasive Species Specialist Group (ISSG) with support from the Overseas Territories Environmental Programme (OTEP) project XOT603, a joint project with the Cayman Islands Government - Department of Environment
Review:
Publication date: 2010-06-08
Recommended citation: Global Invasive Species Database (2024) Species profile: Calluna vulgaris. Downloaded from http://www.iucngisd.org/gisd/species.php?sc=1623 on 07-10-2024.
By preventing native plants from establishing Calluna can also disrupt natural processes of plant regeneration and succession (Rogers & Leathwick, 1996). Phytophagous insect diversity and abundance has also been negatively affected by the invasion of Calluna in New Zealand due to changing habitat, loss or reduction of normal food plants or increased arachnid predation (Keesing, 1993). It can also alter pH and nutrient levels of soil around plants (Rogers, 1995a).
It has also invaded pasture lands in some areas of New Zealand, and causes management problems in recreational and army training lands in New Zealand (Syrett et al., 2000).
Preventative:In areas such as Australia where Calluna is not yet widespread, prevention and education are important to reduce spread. People are encouraged to plant and replace the weed with suitable alternatives. While it is still a permitted import, importation is discouraged. Additionally, care should be taken when buying seeds online or through mail order to check with quarantine that they are free of Calluna and other weeds (CRC, 2003).
Chemical: In New Zealand herbicides may be effective against Calluna. Herbicide trials conducted from 1991 onwards determined that Tordon Brushkiller and Roundup were the most effective herbicides, but that Hi Ester 2,4-D is the most cost effective herbicide for helicopter application over large stands. Helicopter application is the only feasible method for treating large stands of heather, even though it is less effective than hand methods. Herbicides must be applied at intervals of less than two years until the soil seed bank is exhausted (Rogers, 1995a). In Australia there are currently no herbicides registered for use against Calluna (CRC, 2003).
Biological Control: In New Zealand a biological control programme of heather using the heather beetle (Lochmaea suturalis) was implemented in 1990. This beetle is host specific to heather, and can cause substantial damage to plants through defoliation. Beetles were released at Tongariro National Park and surrounding areas, and at Rotorua sites from 1996 onwards. While success was initially poor at high altitude sites, by 2009 beetle populations were high and substantial damage was occurring at all release sites. Researchers expect beetle populations will continue to grow and disperse in subsequent years (Landcare Research, 2007; 2008; 2009).
Hand weeding: Ongoing hand weeding of may be an effective method of eliminating individual plants (Rogers, 1995b).
Grazing:Intense sheep grazing pressure, especially in spring will suppress new growth and flowering, and may eventually eliminate Calluna after a number of years. Large mature plants may need to be slashed first to give sheep access to new shoots. Light grazing is not effective (CRC, 2003).
Fire: Fire is not recommended as a control method. High temperature is required for seed germination in Calluna and thus may help spread the plant (CRC, 2003).