Ericaceae
A genus of evergreen shrubs with some trees. Original distribution confined to Africa and Europe. There are over 500 species, some 470 from South Africa, the rest being endernic to tropical Africa, southern Europe, and the Atlantic islands. In stature they range from shrubs a few centimetres high to trees which sometimes reach 5 m.
Description
Spanish heath is an erect shrub, 0.5-3.0 m high, branched with stems erect or half spreading, the tips being hirsute (shaggy or hair like). Leaves are narrow linear and blade like (5-7 nim), crowded, alternate or in pseudo whorls of 3-4, having very short petioles. Leaves also possess longitudinal grooves on the lower surface and are glabrous (no hair). Erica produces numerous white flowers (buds sometimes have a pink tinge), on slender pedicels (short stems) in the axils of leaves at the end of its branches.
Habitat
In Australia, Erica has been recorded in freshwater riparian zones, the edges of wet sclerophyll forests, dry sclerophyll eucalypt woodlands, and grasslands. In Tasmania it is commonly found along roadsides, in gardens, scrub and in uncultivated paddocks. New Zealand habitats include open disturbed areas and infertile hill country pasture in areas with moderate to fairly high rainfall.
Origin
Erica has become naturalised on both mainland Australia and Tasmania. It is also known to occur widely on the North Island, and northern and eastern areas of the South Island of New Zealand.
In NSW Spanish heath has been reported to occur in the localities of Sydney and the Blue Mountains. Victorian infestations are common and widespread, having been recorded at Fern Tree Gully NP, Melbourne, Mornington Peninsula, Upper Yarra, and Dandenong. Erica has also been observed in the Mt Lofty Ranges, Adelaide, and Watiparinga in Southern Australia.
Tasmanian infestations have been recorded at Port Arthur, Hobart (Mt Wellington), Deloraine, Epping Forest, St Helens, the NW coast and various other locations around the state. Infestations appear to be common and widespread.
In the Meander Valley Region, spanish heath occurs along roadsides in the Western Creek, Elizabeth Town, Birralee, and Bracknell/Liffey areas.
Life Cycle
Seed can germinate all year round but most successful germination occurs during spring and autumn. Light or cold temperatures are required to break the dormancy of the seed. Growth and development of the heath occurs through out the winter, provided temperatures are sufficiently high. Frost damages new growth and appears to be a limiting, factor in the species distribution.
Isolated plants do not flower until they are 3-4 years old. Flower development is initiated during autumn and buds open during mid to late winter. Buds appear to be less susceptible to frost and flowering appears to be delayed at higher altitudes. Flower production has also been observed to decrease with age.
Dispersal
As seeds develop and the petals turn brown and dry out, the flower moves from a pendant to upright position. Seeds are gradually released as the capsules are gently shaken by wind or passing animals. Seed is also most likely dispersed unintentionally in soil on boots and vehicles. Plants are also intentionally cultivated in home gardens.
Properties
Spanish Heath is an invader of natural plant communities and agro-ecosystems. It is generally unpalatable to stock with an exception to goats. New growth will occur after moderate grazing, trampling or fire. Fire is also thought to produce conditions suitable for the germination and establishment of seedlings. Ground disturbance will also promote germination. It is also known to tolerate acid soils.
CONTROL
Biological
Some predation of developing ovaries by a native insect is known to occur in New Zealand. No predators or pathogenic species are known to attack the heath in Tasmania. No biological control program has been developed anywhere in the world.
Physical
Plants may be hand pulled or grubbed, the best tiine for this when soil is moist. They may be slashed in early winter to prevent flowering and subsequent seed set. Burning, followed by an application of glyphosate (Roundup) to regrowth will also give control. Regrowth can occur from large fragments of the root system left in the soil.
Chemical
The following chemical control techniques have been used thoughout Australia.
Cut stump and swab with 3% Garlon 600 in diesel.
Cut stump or basal bark with 100% glyphosate or Grazon DS.
Cut, peel and paint with 8% glyphosate.
Cut stump and swab with 3% Garlon 600 in diesel.
Spot spray with 10g Brush-off + 100ral BS1000, 17Orni Garlon 600 / 100 L water, or 2.5 ml Grazon Ds/L water.
Warning
No registration exists for the use of the above herbicides to control Spanish Heath. Use of herbicides for this purpose can only be done with special permission obtained via the State Registrar of Pesticides.
Cultural
Intensive grazing by goats ( 12 ha -1) can reduce. the level of infestation, but may not provide eradication.
Other Species of Significance
E. andromedaeflora. A shrub up to 1.5 m, branchlets which may or may not be erect with pink flowers. Naturalised in scrub and roadsides on Bruny Island and elsewhere. An escape from commercial production for cut flowers.
E arborea. Tree heath, a much branched shrub up to 3m high with numerous white flowers. Occurs in scrub and on roadsides of Bruny Island and south-east Tasmania. Introduced as an ornamental. In Europe the woody roots are used to produce briar pipes.
E. baccans. A shrub 0.6 - 1.5 m high with numerous half spreading branches and rose red flowers. A garden escape found in abundance in local scrub.
E. caffra. An erect shrub 0.6 - 2 m or more high with slender spreading finely pubescent branches. Flowers are cream or a pale yellow green with a honey scent. Known to occur on the margins of woodlands on Bruny Island and is thought to probably occur elsewhere. Introduced.
E. x willmorei. A shrub with erect branches 0.6 - 1.5 m high. Branchlets are hairy. An escape from commercial production for cut flowers. Has spread from cultivation in some areas.
The text for this page has been supplied by Mark Boersma, Regional Weed Management Officer, Department of Primary Industry and Fisheries.
Note: we are gathering more material for this page, control recommendations and management plans will be included - add a bookmark and call back again.
 
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