Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide


Baccharis halimifolia



Baccharis halimifolia (groundsel-bush)


  • Last modified
  • 08 November 2018
  • Datasheet Type(s)
  • Invasive Species
  • Pest
  • Host Plant
  • Preferred Scientific Name
  • Baccharis halimifolia
  • Preferred Common Name
  • groundsel-bush
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Plantae
  •     Phylum: Spermatophyta
  •       Subphylum: Angiospermae
  •         Class: Dicotyledonae
  • Summary of Invasiveness
  • B. halimifolia is described by Westman et al. (1975) as an "ecological generalist adapted to pioneer stages in succession." Th...

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Male flowers of 'groundsel-bush' or 'sea myrtle'.
TitleMale flowers
CaptionMale flowers of 'groundsel-bush' or 'sea myrtle'.
CopyrightJuan Antonio Campos Prieto
Male flowers of 'groundsel-bush' or 'sea myrtle'.
Male flowersMale flowers of 'groundsel-bush' or 'sea myrtle'. Juan Antonio Campos Prieto
Female flowers of 'groundsel-bush' or 'sea myrtle'.
TitleFemale flowers
CaptionFemale flowers of 'groundsel-bush' or 'sea myrtle'.
CopyrightJuan Antonio Campos Prieto
Female flowers of 'groundsel-bush' or 'sea myrtle'.
Female flowersFemale flowers of 'groundsel-bush' or 'sea myrtle'. Juan Antonio Campos Prieto
Leaf of 'groundsel-bush' or 'sea myrtle'.
CaptionLeaf of 'groundsel-bush' or 'sea myrtle'.
CopyrightJuan Antonio Campos Prieto
Leaf of 'groundsel-bush' or 'sea myrtle'.
LeafLeaf of 'groundsel-bush' or 'sea myrtle'. Juan Antonio Campos Prieto
Typical habit of 'groundsel-bush' or 'sea myrtle'.
CaptionTypical habit of 'groundsel-bush' or 'sea myrtle'.
CopyrightJuan Antonio Campos Prieto
Typical habit of 'groundsel-bush' or 'sea myrtle'.
HabitTypical habit of 'groundsel-bush' or 'sea myrtle'.Juan Antonio Campos Prieto


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Preferred Scientific Name

  • Baccharis halimifolia L. (1753)

Preferred Common Name

  • groundsel-bush

Other Scientific Names

  • Baccharis halimifolia f. subintegrifolia Heering (1907)
  • Baccharis halimifolia var. angustior DC. (1836)

International Common Names

  • English: eastern baccharis; groundsel baccharis; groundsel tree; groundselbush; groundseltree; saltbush; sea myrtle; waterbrush
  • Spanish: tres Marias (Cuba)
  • French: baccharide à feuilles d'halime; séneçon en arbre

Local Common Names

  • Cuba: tapafrío
  • Germany: Gewöhnlicher Kreuzstrauch
  • Mexico: chilca
  • USA: buckbrush; consumption weed; salt bush; silverling

EPPO code

  • BACHA (Baccharis halimifolia)

Summary of Invasiveness

Top of page B. halimifolia is described by Westman et al. (1975) as an "ecological generalist adapted to pioneer stages in succession." The reasons for its success include: prolific seed production; long-range seed dispersal (5-6 km); facultative light requirement for germination; shade tolerant seed production; wide adaptability to soil nutrients and salinity; survival in extreme wet soil conditions; and the ability to resprout following fire. This plant is invading large areas of upper saltmarsh habitats in France, Spain, Australia and some states of the USA in its native range.

Taxonomic Tree

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  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Spermatophyta
  •             Subphylum: Angiospermae
  •                 Class: Dicotyledonae
  •                     Order: Asterales
  •                         Family: Asteraceae
  •                             Genus: Baccharis
  •                                 Species: Baccharis halimifolia

Notes on Taxonomy and Nomenclature

Top of page Plants of this species from the West Indies have been called Baccharis halimifolia var. angustior, but there appears to be little justification for their formal recognition.


Top of page B. halimifolia is a deciduous shrub 1-2(-6) m tall, sometimes single-stemmed from the base and tree-like, more often a densely-branched shrub. Bark of mature plants deeply fissured. Leaves are deciduous, obovate to elliptic or narrowly elliptic-oblanceolate, 3-nerved, 2-6 cm long, smooth-margined or with one tooth or one to three pairs of coarse teeth on the upper margins, the surfaces slightly resinous, usually with small dots. Florets closely clustered in heads surrounded by involucral bracts, the heads borne in tight aggregations. Heads are of two sexes, each produced on a separate plant (i.e. the species is dioecious): the staminate heads (pollen-producing, with sterile ovaries) with only tubular, 5-lobed corollas, greenish to dull white; the pistillate heads (with fertile ovaries) with only thread-like corollas. Fruits ('cypselae' or achenes) are 1-seeded, nearly cylindric, 1.3-1.8 mm long, topped by a ring of numerous, slender, flexible, silvery-white bristles (the 'pappus'), which elongates at achene maturity to 10-12 mm long, much longer than the involucre. The small fruits are shed with the pappus, a wind-catcher that enables fruit dispersal over a wide area. The common name 'silverling' alludes to the silvery aspect of pistillate plants in the autumn, when the pappus of each maturing fruit elongates and protrudes from the head.

Plant Type

Top of page Perennial
Seed propagated


Top of page B. halimifolia occurs in all states bordering the Atlantic Ocean and Gulf of Mexico in USA (Duncan and Duncan, 1988), plus the Caribbean and into northeastern Mexico as far south as Veracruz and San Luis Potosí (USDA-NRCS, 2001, 2005).

It is present along the Black Sea coast of Abkhazia, Georgia (Westman et al., 1975), on the north coast of Spain (Allorgue and Allorgue, 1941; Campos et al., 2000) and in France (Dupont, 1966). It has also been introduced to Australia and New Zealand.

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes


Georgia (Republic of)Restricted distributionIntroduced Invasive Westman et al., 1975; EPPO, 2014

North America

CanadaPresentPresent based on regional distribution.
-Nova ScotiaRestricted distributionEPPO, 2014
MexicoRestricted distributionUSDA-NRCS, 2001; EPPO, 2014
USAPresentNative Invasive Tarver et al., 1988
-AlabamaPresentNativeMohr, 1901; EPPO, 2014
-ArkansasPresentNativeSmith, 1988; EPPO, 2014
-ConnecticutPresentNativeDowhan, 1979; EPPO, 2014
-DelawarePresentNativeRalph, undated; USDA-NRCS, 2005; EPPO, 2014
-FloridaPresentNativeUSDA-ARS, 2005; USDA-NRCS, 2005; EPPO, 2014
-GeorgiaWidespreadNative Invasive Duncan and Kartesz, 1981; EPPO, 2014
-LouisianaWidespreadNative Invasive Thomas and Allen, 1997; EPPO, 2014
-MarylandPresentNativeBrown and Brown, 1972; EPPO, 2014
-MassachusettsPresentNativeSorrie and Somers, 1999; EPPO, 2014
-MississippiWidespreadNativeLowe, 1921; EPPO, 2014
-New JerseyPresentNativeUSDA-ARS, 2005; USDA-NRCS, 2005; EPPO, 2014
-New YorkPresentNativeMitchell, 1986; EPPO, 2014
-North CarolinaPresentNative Invasive Radford et al., 1964; EPPO, 2014
-OklahomaPresentNativeTaylor and Taylor, 1989; EPPO, 2014
-PennsylvaniaPresentNativeWherry et al., 1979; EPPO, 2014
-Rhode IslandPresentNativeGeorge, 1992; EPPO, 2014
-South CarolinaWidespreadNative Invasive Radford et al., 1964; EPPO, 2014
-TexasWidespreadNative Invasive Hatch et al., 1990; EPPO, 2014
-VirginiaWidespreadNativeHarvill et al., 1977; EPPO, 2014
-West VirginiaPresentNativeHarvill et al., 1977; EPPO, 2014

Central America and Caribbean

BahamasPresentNativeVan Deelen, 1991; EPPO, 2014
CubaPresentNativeVan Deelen, 1991; EPPO, 2014


BelgiumRestricted distributionIntroducedCaño et al., 2013; EPPO, 2014
FranceRestricted distributionIntroduced Invasive Dupont, 1966; Caño et al., 2013; EPPO, 2014Locally abundant in estuaries in west; scattered populations in north and south
-CorsicaAbsent, no pest recordEPPO, 2014
ItalyRestricted distributionIntroducedCaño et al., 2013; EPPO, 2014
NetherlandsAbsent, formerly presentCaño et al., 2013; EPPO, 2014
SpainRestricted distributionIntroduced Invasive Campos and Herrera, 1997; Caño et al., 2013; EPPO, 2014Naturalized in Bay of Biscay since 1906, abundant in estuaries in northern Spain
UKRestricted distributionIntroduced Not invasive Stace, 1991; Weber, 2003; EPPO, 2014


AustraliaRestricted distributionIntroduced Invasive Westman et al., 1975
-Australian Northern TerritoryRestricted distributionIntroduced Invasive Westman et al., 1975
-New South WalesWidespreadIntroduced Invasive Westman et al., 1975; EPPO, 2014
-QueenslandWidespreadIntroduced Invasive Bailey, 1900; Winders, 1937; EPPO, 2014
-Western AustraliaRestricted distributionIntroduced Invasive Westman et al., 1975
New ZealandRestricted distributionIntroducedUSDA-ARS, 2005; EPPO, 2014

History of Introduction and Spread

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Groundsel-bush was probably introduced as an ornamental into western Europe (France and Spain). It was first recorded as naturalized in the Bay of Biscay in 1906, where it now forms stable and locally abundant populations in almost all the estuaries of northern Spain and western France (Caño et al., 2013). It has been naturalized in Hampshire, UK, since about 1942 (Stace, 1991) and forms scattered populations in northern and southern France, Belgium, Netherlands, and Italy (Caño et al., 2013). It was introduced into Queensland, Australia, as an ornamental plant in the latter half of the 19th century and had naturalized by 1888 (Parsons and Cuthbertson). It continued to spread along the coastal areas of southeastern Queensland (north to Miriam Vale Shire) and by 1941 it was also naturalized along the coast of New South Wales. Scattered plants have occurred as far west as the Chinchilla region (Bailey, 1900).


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B. halimifolia grows on beaches and marshes near the shore, and in various inland habitats including pastures, old fields, ditches and roadsides (Stalter, 1976).

Habitat List

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Terrestrial – ManagedManaged forests, plantations and orchards Present, no further details Harmful (pest or invasive)
Managed grasslands (grazing systems) Present, no further details Harmful (pest or invasive)
Disturbed areas Present, no further details
Rail / roadsides Present, no further details
Terrestrial ‑ Natural / Semi-naturalNatural forests Present, no further details Harmful (pest or invasive)
Wetlands Present, no further details Harmful (pest or invasive)
Coastal areas Present, no further details Harmful (pest or invasive)

Hosts/Species Affected

Top of page B. halimifolia is not a weed of crops, but negatively affects characteristic species from marsh habitats.

Biology and Ecology

Top of page Genetics

The chromosome number is n=9 in the USA and Australia (Westman et al., 1975).

Physiology and Phenology

Seed germination ranges from 70 to 99% (Diatloff, 1964; Panetta 1979b). Most germination occurs in the autumn/winter period. Reduced germination in low light conditions may have the effect of reducing competition in areas of dense herb coverage (Westman et al., 1975). There is no dormancy requirement for seed, although fluctuations of either light or temperature increased the rate of germination (Panetta, 1979c). Self-thinning, graminoid competition, and heavy litter reduce seedling establishment and maintain a stable stem density. Shade tolerance allows B. halimifolia to maintain a pool of seedlings in the understorey until disturbance provides an opportunity for release and continued regeneration.

In Florida and further north in North America, B. halimifolia is deciduous whereas in Queensland and New Wales (Australia) it is evergreen; in northern Spain is partially deciduous.

Reproductive Biology

Plants do not normally flower in the first year of growth. Flowering in the USA occurs mainly in August-December; in Spain it is in September-October; in Australia, flowering is also in the autumn months, the male plants flowering first and continuing to flower after the female plants have finished flowering (Parsons and Cuthbertson, 1992). Plants of groundsel-bush as young as 3 years may produce viable seed. Because it is dioecious, male and female plants are necessary for seed production. Disturbance and the creation of overstorey gaps stimulate seed production. Seed production decreases with plant age and density but increases with available light. Plants about 9 years old produced 31% less seed than did 4-year-old plants. Extreme shade yields lower numbers of seeds that are better filled and have a higher germination rate than seeds produced in full sunlight (Panetta, 1977, 1979a,b).

B. halimifolia is probably one of the most prolific seed producers ever recorded. The numbers of seeds per female plant in one season is variously estimated at 10,000 (Auld, 1970), 376,000 (Panetta 1979a), 450,000-900,000 (McFadyen, 1985), or 1,500,000 (Westman et al., 1975).

Environmental Requirements

B. halimifolia is classified as a facultative wetland plant (FACW) by USDA-NRCS (2005). FACW plants usually occur in wetlands (67-99% probabilty). It does not tolerate heavy clay soils but can be successfully grown in nutrient-poor soil. Most native coastal plain habitats are sandy. It is a fast-growing plant and will quickly regrow, even if cut back to the base. It is able to survive periodic flooding and drying and is resistant to salt spray.

It is an early successional, woody invader of disturbed lowlands throughout its range. In the USA, it replaces sawgrass (Cladium spp.), freshwater marsh, marl and wet prairie communities following drainage in southern Florida. It is characteristic of cut-over and partially drained, deep-water swamps in southeastern Louisiana. Despite its early-seral nature, groundsel-bush is shade tolerant. It persists under a pine canopy and may reach carrying capacity in as little as 4 years.


In the USA, B. halimifolia predominantly grows in association with marsh elder (Iva frutescens) along the tidal marsh/upland border, an easily recognized ecotone community in the Mid-Atlantic States. Baccharis is more likely to be found at slightly higher elevations in the marsh than Iva. The former is not restricted to saline marshes, but also occupies open coastal, non-tidal wetlands, whereas Iva is almost always endemic in tidal saline marshes. Wax myrtle (Myrica cerifera [Morella cerifera]), is frequently associated with Baccharis, but grows at slightly higher elevations in the marsh and often continues into the uplands. Zonation patterns are frequently apparent in the saltbush ecotone; Iva at the lowest elevations, then Baccharis, with Myrica growing in the highest part of the marsh. Saltmeadow hay (Spartina patens) is the typical herbaceous plant growing among saltbushes. The herbaceous layer is variable in species composition and cover and contains Teucrium canadense, Panicum virgatum, Myrica pensylvanica [Morella caroliniensis] and Phragmites australis.

In Australia, it is associated with Imperata cylindrica or Melaleuca quinquenervia.

Soil Tolerances

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Soil drainage

  • free
  • impeded
  • seasonally waterlogged

Soil reaction

  • acid
  • alkaline
  • neutral
  • very acid

Soil texture

  • heavy
  • light
  • medium

Special soil tolerances

  • saline

Natural enemies

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Natural enemyTypeLife stagesSpecificityReferencesBiological control inBiological control on
Anacassis fuscata Herbivore
Anacassis phaeopoda Herbivore Leaves
Aristotelia ivae Herbivore Leaves Queensland
Bucculatrix ivella Herbivore Leaves
Dimeriella melioloides Pathogen Leaves/Stems
Helipodus intricatus Herbivore
Hellinsia balanotes Herbivore Growing point/Stems
Leioplacis elliptica Herbivore
Lorita baccharivora Herbivore Inflorescence Florida; Queensland; Texas
Megacyllene mellyi Herbivore Stems Queensland
Metallactus nigrofasciatus Herbivore Leaves
Metallactus patagonicus Herbivore Leaves
Neolasioptera lathami Herbivore
Neolasioptera rostrata Herbivore
Oidaematophorus balanotes Herbivore Queensland
Puccinia evadens Pathogen Leaves/Stems
Rhopalomyia californica Herbivore Growing point/Inflorescence/Leaves Australia
Stolas fuscata Herbivore Leaves
Tephritis palmeri Herbivore
Trirhabda bacharidis Herbivore Leaves

Notes on Natural Enemies

Top of page Larvae and adults of various species of beetles and moths are capable of defoliating B. halimifolia in its native range. A survey of the insect fauna on B. halimifolia and B. neglecta was undertaken in 1982-86 in Texas, Louisiana (USA) and northern Mexico. The 133 phytophagous insects that were collected included 11 species which were considered to be exclusive to Baccharis (Palmer, 1987). Several have been introduced into Australia as agents of biological control for B. halimifolia (see Biological Control).

Phytophagous Brazilian insects have also been successfully used to control introduced Baccharis species in Australia. Similar techniques show promise for use in the USA (DeLoach et al., 1986).

Groundsel bush rust, Puccinia evadens, is both a leaf and a stem pathogen causing defoliation during summer and winter and stem dieback over summer.

Means of Movement and Dispersal

Top of page Natural Dispersal (Non-Biotic)

The plant produces small seeds which are firmly attached to the pappus and easily dispersed by wind. In a steady wind of about 17 km/h, seeds drift as far as 140 m from a shrub 2 m in height (Diatloff, 1964). Seeds from mature plants drift in the breeze like thistle seeds, most falling within a few metres of the parent bush. Wind updraughts can carry seeds many kilometres. Seeds may also be dispersed by water.

Intentional Introduction

In some regions where B. halimifolia is a weed, it was introduced as a garden shrub in coastal areas because of its resistance to salinity.

Impact Summary

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Animal/plant collections None
Animal/plant products None
Biodiversity (generally) Negative
Crop production None
Environment (generally) Negative
Fisheries / aquaculture None
Forestry production None
Human health None
Livestock production None
Native fauna None
Native flora Negative
Rare/protected species Negative
Tourism None
Trade/international relations None
Transport/travel None


Top of page B. halimifolia rapidly colonizes disturbed areas, especially overgrazed pastures. It competes with pasture species for water and nutrients and is toxic to livestock, causing staggering, trembling, convulsions, diarrhoea, and other gastrointestinal symptoms. It spreads rapidly by wind-borne seeds making clearance from paddocks a very time consuming and expensive task.

Impact: Biodiversity

Top of page In native Melaleuca wetlands in Australia, B. halimifolia can form a dense understorey, suppressing growth of native sedges and interfering with the natural ecosystem. It can become abundant in the vegetation along watercourses and in coastal woodlands and forest areas if not controlled. Along Spanish and French coasts it replaces natural saltmarsh vegetation endangering some characteristic species and habitats.

Social Impact

Top of page The wind-dispersed seed can be a nuisance in urban areas where it sticks to insect screens and germinates in home gardens. The air-borne pollen and seed 'fluff' are thought to be potential allergens.

Risk and Impact Factors

Top of page Invasiveness
  • Invasive in its native range
  • Proved invasive outside its native range
  • Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
  • Highly mobile locally
  • Has high reproductive potential
  • Has propagules that can remain viable for more than one year
Impact outcomes
  • Damaged ecosystem services
  • Ecosystem change/ habitat alteration
  • Negatively impacts agriculture
  • Negatively impacts animal health
  • Reduced native biodiversity
Impact mechanisms
  • Competition - monopolizing resources
Likelihood of entry/control
  • Highly likely to be transported internationally deliberately
  • Difficult to identify/detect as a commodity contaminant
  • Difficult/costly to control


Top of page The native groundsel-bush is recommended as a garden shrub or hedge in Florida, USA, because of its hardiness, freedom from disease, autumn flowering and resistance to salt spray. The female plants, in particular, with their densely silver-green aspect, are beautiful when few other plants are flowering. Plants can be trained to a single trunk which will grow into a tree up to 6 m high. It is a useful shrub for reclaiming moist or wet sites, including retention areas and drainage ponds.

Although it apparently has little or no value as a food source for game animals ('wildlife'), B. halimifolia provides cover and nesting habitat for various species of birds. Bees and small butterflies use the abundant nectar from the male flowers, which in turn attract songbirds to forage on the insects. B. halimifolia is known to be an important part of the honey flora for Queensland apiaries in Australia.

Uses List

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  • Agroforestry

Similarities to Other Species/Conditions

Top of page B. halimifolia closely resembles the Mexican species B. heterophylla. Where both occur in Veracruz, Mexico, B. halimifolia can be recognized by its habitats along the coast or coastal plain, its more gradate, blunt-tipped involucral bracts, and its longer pappus. Plants from central Nuevo León, Mexico, have narrower leaves than typical B. halimifolia, but in most respects they are more similar to it than to B. heterophylla. B. halimifolia hybridizes with B. neglecta where the two meet in east Texas, USA.

Prevention and Control

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Cultural Control

Overgrazing and drainage favour invasion by B. halimifolia and convert salt marshes into shrublands. The maintenance of a dense sward of pasture or native cover vegetation where possible may effectively shade the surface of the ground.

In grazing situations good pasture management will greatly reduce groundsel-bush invasions. Slashing, timely use of fertilizer, and the management of stocking rates can assist in control by maintaining a healthy pasture. Good pastures provide competition to limit re-invasion of this species. For tall, dense infestations, burning can reduce the amount of above-ground material (and even kill the odd plant) making it a lot easier to spray regrowth. Annual burning does not reduce existing plant numbers, but allows grasses to establish more quickly and outcompete B. halimifolia seedlings. Regular slashing over a period of several years will result in a decreased level of infestation.

In non-grazing situations reforestation will eventually assist in control of groundsel-bush. However, it is important to ensure that seed production is prevented while trees are establishing.

Mechanical Control

Groundsel-bush is intolerant of fire and tends to occupy only unburned sites. Post-fire colonization depends on proximity of a seed source and wind dispersal. Various mechanical and chemical techniques have been developed to control B. neglecta, B. halimifolia and B. pilularis. Mechanical methods such as digging (grubbing), cutting, root-ploughing, burning, bulldozing and shredding have been in use for many years with variable success (Winders, 1937; Hoffman, 1968; Everitt et al., 1978). Even when top removal is complete, these measures are labour intensive and often have to be repeated every 2-3 years because the plant is usually not killed. Grubbing is most effective when plants are young or densities are low because the roots are shallow (Mutz et al., 1979). Burning and shredding are not usually effective because resprouting from above-ground buds may occur in Baccharis as early as 60 days after treatment (Scifres and Haas, 1974; Hobbs and Mooney, 1985).

Chemical Control

Baccharis species are problem weeds of rangelands, pastures, parks, recreational areas, and floodplains. Mowing and broadleaf herbicide treatments at 1- to 3-year intervals may provide control, although such control methods are often not cost-effective.

Herbicides, although initially expensive to apply, may give long-term control. Treatments of glyphosate, 2,4-D acid or 2,4-D amine achieved over 90 percent control of B. halimifolia in a variety of tests (Auld, 1970; Armstrong and Wells, 1979) while a 2,4-D low-volatile ester was effective against B. neglecta (Scifres and Haas, 1974).

Although foliar sprays are effective, the hazards of drift into inhabited areas, or susceptible crops, may restrict their use. Pelleted chemicals are slightly more expensive but may be an attractive alternative. They are not volatile, extend the period of effective treatment and are easy to apply. Excellent control of B. neglecta in Texas, USA, was achieved by Mutz et al. (1979) and Scifres (1980) by broadcasting picloram or tebuthiuron.

Biological Control

Since the biological control programme began in Australia in 1967 over thirty-five different insects have been tested against B. halimifolia but only six have become permanently established in the field (Queensland Government, 2004):

The stem borer beetle Megacyllene mellyi is restricted to areas adjacent to salt marshes where the sap flow in the host plant is lower (newly hatched larvae are drowned by the heavier sap flow in plants growing in non-saline soils). Dense populations of this insect can reduce B. halimifolia infestations in suitable habitats (McFadyen, 1987).

The plume moth Oidaematophorus balanotes [Hellensia balanotes] is present in all areas. Damage is caused by larvae tunnelling in the stems and varies from severe dieback to death of individual branches. Populations of the moth appear to be restricted by ant predation on the eggs and young larvae which restricts plant damage (Palmer and Haseler, 1992a).

Larvae of the gall-fly Rhopalomyia californica feed within developing shoots and buds. Initially this insect caused heavy damage when it was released. However, soon after its release it was attacked by a small native wasp that drastically reduced gall numbers. Overall damage to the plant is minimal (Palmer et al., 1993).

The groundsel bush leaf beetle Trirhabda baccharidis is restricted to similar habitats as the stem borer where the larvae can form suitable cocoons and pupate in the soil. Plants will be totally defoliated in autumn but can recover and are in full leaf next spring. In some years larvae severely damage the buds and flowers (Palmer and Haseler, 1992b).

The larvae of the leaf skeletoniser Aristotelia ivae feed on the soft leaf tissue leaving the skeletal woody veins. Though widespread, populations do not become large enough to cause significant damage. It is most commonly found in the spring on new leaves (Diatloff and Palmer, 1988).

The larvae of the leaf miner Buccalatrix ivella mine the leaf blades and later skeletonize the leaves in a manner similar to Aristotelia. This insect is widespread within the Australian range of B. halimifolia and causes minor damage (Palmer and Diatloff, 1987).

For details of other biocontrol trials using insects, see for example Metallactus patagonius (McFadyen, 1987) and Stolas fuscata (Boldt, 1989b).

The rust fungus Puccinia evadens was released against B. halimifolia in Florida, USA, in 1998 and has now established (Queensland Government, 2004).

Integrated Control

The best approach is usually to combine different methods. Control may include chemical, mechanical, fire and biological methods combined with land management changes to suit the situation.


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Allorgue P, Allorgue V, 1941. Les ravins à Fougères de la corniche vasco-cantabrique. Bulletin de la Societé Botanique de France, 88:92-111.

Armstrong TR, Wells CH, 1979. Herbicidal control of Baccharis halimifolia. Proceedings of the 7th Asian-Pacific Weed Science Society Conference, Sydney, Australia, 1979, 153-155.

Auld B, 1970. Groundsel bush. A dangerous woody weed of the far north coast. Agricultural Gazette of New South Wales, 80:32-34.

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Boldt PE, 1989. Baccharis, (Asteraceae), a review of its taxonomy, phytochemistry, ecology, economic status, natural enemies and the potential for its biological control in the United States. Texas, USA: Texas Agricultural Experiment Station, Texas A & M University.

Boldt PE, 1989. Host specificity studies of Stolas fuscata (Klug) (Coleoptera: Chrysomelidae) for the biological control of Baccharis salicifolia (R. & P.) Pers. (Asteraceae). Proceedings of the Entomological Society of Washington, 91(4):502-508.

Brown RG, Brown ML, 1972. Woody Plants of Maryland. Baltimore, USA: Port City Press, Inc.

Campos JA, Herrera M, 1997. La flora introducida en el País Vasco. Itinera Geobotanica, 10:235-255.

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Caño L, Campos JA, García-Magro D, Herrera M, 2013. Replacement of estuarine communities by an exotic shrub: distribution and invasion history of Baccharis halimifolia in Europe. Biological Invasions, 15(6):1183-1188.

DeLoach CJ, Boldt PE, Cjordo HA, et al, 1986. Weeds common to Mexican and US rangelands: proposals for biological control and ecological studies. In: Patton DR, Gonzales V, Carlos E, Medina AL, et al., technical coordinators. Management and Utilization of Arid Land Plants: Symposium proceedings, Feb. 18-22 1985, Saltillo, Mexico. Rocky Mountain Forest and Range Experiment Station, General Technical Report RM-135. Fort Collins, USA: US Department of Agriculture, Forest Service, 49-68.

Diatloff G, 1964. How far does groundsel seed travel? Queensland Agricultural Journal, 51:354-356.

Diatloff G, Palmer WA, 1988. The host specificity and biology of Aristotelia ivp Busck (Gelechiidae) and Lorita baccharivora Pogue (Tortricidae), two microlepidoptera selected as biological control agents for Baccharis halimifolia (Asteraceae) in Australia. Proceedings of the Entomological Society of Washington, 90(4):458-461

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