Common Name: Bush Groundsel

General Information

Baccharis halimifolia is a freely-branched, deciduous shrub or small tree that usually grows 100 - 300cm tall, exceptionally to 600cm[]. The main stem seldom exceeds 16cm in diameter[]. In some climates (Queensland in Australia, for example) the plant has become evergreen[].
The plant is sometimes harvested from the wild as a medicine and source of fuel. Its presence is said to indicate oil beneath the soil. An attractive ornamental, it is easy to grow, has attractive autumn colouring and can also be used as a hedge. The plant is also valuable for soil stabilization and has potential to be a pioneer when restoring woodland.
Baccharis halimifolia has escaped from cultivation in various temperate areas, where it tends particularly to invade upper saltmarsh areas. It was introduced in Australia, where it now infests large areas along the eastern coast, prompting the search for biological control agents[]. Its success as an invasive weed is attributed to production of a large number of seeds that are widely dispersed by the wind, shade tolerant germination and seedlings, tolerance to wet soils and salinity, and ability to resprout after a fire[].

Known Hazards

The leaves contain a cardiotoxic glycoside known to cause the death of sheep if they eat about one percent of their body weight in leaves[]. Visible symptoms of poisoning range from mild depression followed by recovery, to extreme listlessness and stupor followed by death. The toxic compound attacks the hepatic and circulatory systems[].
The plant may aggravate hay fever symptoms for some people[].

Botanical References

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Range

Eastern and southern N. America - Nova Scotia to Florida, west to Oklahoma and Texas; Caribbean - Bahamas, Cuba; S. Mexico - Veracruz

Habitat

Open woods, thickets and borders of marshes near the coast[], often in saline soils[]. Open sandy places, wet fields, marshes, beaches, disturbed sites, roadsides, old fields; at elevations up to 100 metres[].

Properties

Medicinal Rating
Other Uses Rating
Habit	Deciduous Shrub
Height	3.50 m
Growth Rate	Medium
Pollinators	Wind, Insects
Self-fertile	No
Cultivation Status	Ornamental, Wild

Cultivation Details

Plants are hardy to about -15°c[].
Succeeds in a sunny position, though also tolerant of moderate shed[, ]. Grows well in any well-drained soil[, ], from moderately heavy clays to pure sands[]. Tolerates saline conditions and dry soils[, ]. A useful shrub for coastal situations, resisting maritime exposure[]. The plant can tolerate occasional inundation of the soil[].
A fast-growing plant, it is very tolerant of pruning and can be cut right back to the base if required[].
Plants are intolerant of fire and can only regenerate on a burnt site by means of seeds being blown in from surrounding areas[].
Plants can begin producing seed in their third year of growth[]. The plant 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 between 10,000 and 450,000 - 900,000, whilst one report has estimated as high as 1,500,000[].
The leaves secrete a sticky resin, thought to deter herbivory by all but the most specialized insects[].
This species hybridizes in the wild with Baccharis neglecta and Baccharis angustifolia[].
A dioecious species - both male and female forms must be grown if fruit and seed are required.

Edible Uses

None known

Medicinal

The plant is used as a palliative and demulcent in the treatment of consumption and cough[].

Agroforestry Uses:

A good fast-growing hedge for exposed maritime conditions[, ]. It retains its leaves into the new year but is rather bare in late winter[].
Plants have an extensive root system and can be grown on sand or thin coastal soils in order to bind the soil[].
The plant rapidly colonizes disturbed sites. It thus has excellent potential for use as a pioneer plant, though only within its native range due to its propensity to become invasive[, ].
The presence of this plant growing wild was supposed to indicate areas where oil might be found[].

Other Uses

Resinous secretions on the leaves and wood make this a useful fuel[]. It is a fairly small plant though and would not be a very productive source.

Propagation

Seed - no pre-treatment is required[]. Surface sow in pots a cold frame in the spring, do not let the compost dry out. Germination usually takes place within 1 - 2 weeks[]. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the cold frame for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts.
Cuttings of half-ripe wood, mid summer in a frame. Very easy[].
Cuttings of mature wood of the current seasons growth, late autumn in a frame. Easy[].