This page lists weeds of concern on conservation land in New Zealand (with references).
This list is from: Owen, S.J. 1996. Ecological weeds on conservation land in New Zealand: a database. 118p. Department of Conservation, Wellington.
Other weeds recognized as potential problems at the time of publication of the printed version are listed separately. Many of these weeds are now subject to control.
An updated list will be produced sometime in the near future. This list is put out as it was found in the 1996 publication. If you have any comments, send them to Chris Buddenhagen (cbuddenhagen@doc.govt.nz).
A printed version of this is available from:
PHONE: 64-4-471-3136 FAX: 64-4-471-3279
E-mail: svaughan@doc.govt.nz
Weeds of concern on conservation lands in New Zealand | |||||
Botanical name | Species common name | Lit. Ref | Growth form | year of naturalisation in NZ | Country/area of origin |
Acacia dealbatum | silver wattle | 2,3,10 | Tree (6-10m) | 1870 | E Australia |
Acacia longifolium | Sydney golden wattle | 2,12 | Tree (6-10m) | 1897 | E Australia |
Acacia paradoxum | kangaroo acacia | 2 | Tree (<6m) | 1911 | W & E Australia |
Acer pseudoplatanus | sycamore | 8, 12 | Tree (>10m) | 1880 | C & S Europe |
Acmena smithii | monkey apple | Tree (>10m) | 1982 | E.Australia | |
Agapanthus praecox | agapanthus | 11 | Bulb herbs | 1952 | Sth Africa |
Ageratina adenophora | Mexican devil | 1,3 | Erect herb | 1931 | Mexico |
Ageratina riparia | mist flower | 1 | Erect herb | 1931 | Mexico, W. Indies |
Agrostis capillaris | browntop | Grass | 1867 | Europe, temp. Asia | |
Allium triquetrum | onion weed | 11 | Bulb herbs | 1899 | SW Europe, N Afr. |
Alnus glutinosa | alder | Tree (>10m) | 1914 | Eurasia, N Africa | |
Alocasia brisbanensis | elephant's ear | 12 | Bulb herbs | 1867 | trop Asia |
Alternanthera philoxeroides | alligator weed | 2,11,12 | Aquatic | 1906 | Brazil |
Ammophila arenaria | marram | 2, 12 | Grass | 1873 | Europe, Nth Africa |
Anredera cordifolia | madeira vine | 2,11,12 | Vine | 1940 | trop S America |
Araujia sericifera | moth plant | Vine | 1888 | S Brazil, Argentina | |
Aristea ecklonii | aristea | Bulb herbs | 1975 | trop & S Africa | |
Arrhenatherum elatius | tall oat grass | Grass | 1871 | Eurasia, Nth Africa | |
Arum italicum | Italian lily | Bulb herbs | 1945 | Eurasia | |
Arundo donax | giant reed | 3 | Grass | 1936 | Eurasia |
Asparagus asparagoides | smilax | 2 | Vine | 1905 | trop & S Africa |
Asparagus scandens | climbing asparagus | 2 | Vine | 1970 | trop & S Africa |
Berberis darwinii | Darwin's barberry | 11 | Tree (<6m) | 1946 | S. Chile, Argentina |
Berberis glaucocarpa | barberry | Tree (6-10m) | 1916 | W Himalaya | |
Bromus tectorum | cheatgrass, downy brome | 1, 12 | Grass | 1870 | Mediterranean |
Buddleja davidii | buddleia | 8 | Shrub (3-5m) | 1946 | China |
Caesalpinia decapetala | Mysore thorn | 1,3,12 | Tree (6-10m) | 1965 | India |
Calluna vulgaris | heather | Shrub (<3m) | 1910 | Eurasia, N Africa | |
Carduus nutans | nodding thistle | Bi/Annual | 1889 | Eurasia, N Africa | |
Carex longebrachiata | Australian sedge | Rush | 1906 | Australia | |
Celastrus orbiculatus | climbing spindleberry | Tree (6-10m) | 1981 | NE temp Asia | |
Cestrum aurantiacum | orange cestrum | Shrub (<3m) | 1958 | Guatemala | |
Cestrum elegans | red cestrum | 2 | Shrub (3-5m) | 1958 | Mexico |
Chrysanthemoides monilifera | bone seed | 2 | Shrub (3-5m) | 1870 | S Africa |
Cirsium spp. | thistles | 2 | Bi/Annual | 1870 | Eurasia |
Clematis flammula | clematis | Vine | 1968 | Eurasia, N Afr. | |
Clematis vitalba | old man's beard | 2 | Vine | 1940 | Europe, SW Asia |
Cobaea scandens | cathedral bells | Vine | 1946 | C & S America | |
Convolvulus arvensis | convolvulus, field bindweed | 10 | Vine | 1880 | N temperate |
Cortaderia jubata | purple pampas | 4, 5 | Grass | 1965 | America |
Cortaderia selloana | pampas | 2,5 | Grass | 1925 | America |
Cotoneaster glaucophyllus | cotoneaster | 2 | Shrub (3-5m) | 1982 | China |
Cotoneaster simonsii | Khasia berry | Shrub (3-5m) | 1958 | Burma | |
Crataegus monogyna | hawthorn | 2,10 | Tree (6-10m) | 1899 | Europe |
Crocosmia x crocosmiiflora | montbretia | 2 | Bulb herbs | 1935 | trop S America |
Cytisus scoparius | broom | 2 | Shrub (<3m) | 1872 | Eurasia |
Dactylis glomerata | cocksfoot | 12 | Grass | 1867 | Eurasia, Nth Africa |
Dipogon lignosus | mile-a-minute | 2 | Vine | 1871 | S Africa |
Echium vulgare | viper's bugloss | 10,11 | Bi/Annual | 1870 | Eurasia |
Egeria densa | egeria | Aquatic | 1946 | sub-trop America | |
Ehrharta erecta | veld grass | 2 | Grass | 1944 | Sth Africa |
Ehrharta villosa | pyp grass | 2 | Grass | 1990 | Sth Africa |
Elaeagnus x reflexa | elaeagnus | Vine | 1940 | ?Japan | |
Equisetum arvense | horsetail | Fern | 1922 | N temperate | |
Erica lusitanica | Spanish heath | 2, 12 | Shrub (<3m) | 1926 | SW Europe |
Erigeron karvinskianus | Mexican daisy | Mat forming | 1940 | Mexico | |
Eriobotrya japonica | loquat | 1 | Tree (<6m) | 1982 | China, Japan |
Euonymus europaeus | spindleberry | Tree (<6m) | 1958 | Europe | |
Euonymus japonicus | Japanese spindleberry | 2 | Tree (6-10m) | 1980 | Jap, China, Korea |
Festuca arundinacea | Grass | 1871 | |||
Glyceria fluitans | floating sweetgrass | Grass | 1872 | almost cosmopolitan | |
Gymnocoronis spilanthoides | Senegal tea | Aquatic | |||
Hakea gibbosa | hakea, downy | Tree (<6m) | 1937 | NSW | |
Hakea salicifolia | hakea, willow-leaved | 2 | Tree (<6m) | 1908 | E Australia |
Hakea sericea | hakea, prickly | 2,3,12 | Tree (<6m) | 1883 | Tas., E Australia |
Hedera helix | ivy | 1,2 | Vine | 1873 | temp. Europe, Asia |
Hedychium flavescens | yellow ginger | 1, 12 | Erect herb | 1898 | Himalayas |
Hedychium gardnerianum | kahili ginger | 1, 12 | Erect herb | 1940 | India |
Hieracium spp. | hawkweed | Mat forming | 1878 | Europe | |
Humulus lupulus | hops | 11 | Vine | 1872 | Europe, C&W Asia |
Hydrilla verticillata | hydrilla | 1, 12 | Aquatic | 1963 | Eurasia |
Hydrodictyon reticulatum | water net | Aquatic | 1986 | Eurasia | |
Hypericum androsaemum | tutsan | 2 | Shrub (<3m) | 1870 | S & W Europe |
Hypericum perforatum | St John's wort | 2, 5 | Erect herb | 1869 | Eur, W Asia, N Afr |
Ipomoea indica | blue morning glory | 1, 11 | Vine | 1950 | pantropical |
Iris foetidissima | stinking iris | Bulb herbs | 1945 | Europe & N Afr | |
Iris pseudacorus | yellow flag iris | 11 | Bulb herbs | 1938 | Eur, Asia, N Afr |
Jasminium humile | yellow jasmine | Shrub (<3m) | 1958 | temp Himalaya, SW China | |
Jasminum polyanthum | jasmine | Vine | 1980 | W China | |
Juglans ailantifolia | Japanese walnut | Tree (>10m) | 1983 | Japan | |
Juncus acutus | sharp rush | 2, 11 | Rush | 1923 | Europe, Africa, N Am |
Juncus articulatus | jointed rush | 11 | Rush | 1864 | Eurasia, N Am, N Africa |
Juncus bulbosus | bulbous rush | 11 | Rush | 1896 | Eurasia, N Africa |
Juncus effusus | soft rush | 2 | Rush | 1864 | Eurasia |
Juncus squarrosus | heath rush | Rush | 1910 | Eur, N Afr, Iceland | |
Lagarosiphon major | lagarosiphon | 12 | Aquatic | 1950 | trop & S Africa |
Lantana camara var. aculeata | lantana | 1,6 | Shrub (<3m) | 1912 | trop America |
Leycesteria formosa | Himalayan honeysuckle | 2 | Shrub (<3m) | 1878 | temp Himalaya |
Ligustrum lucidum | tree privet | 2,12 | Tree (>10m) | 1958 | China, Korea |
Ligustrum sinense | Chinese privet | 2 | Tree (<6m) | 1950 | China |
Lolium perenne | perennial ryegrass | Grass | 1855 | Eur, temp Asia, N Afr | |
Lonicera japonica | Japanese honeysuckle | 1,2,12 | Vine | 1926 | E Asia |
Lotus pedunculatus | lotus | Mat forming | 1867 | Europe, Asia, N Afri | |
Lupinus arboreus | tree lupin | 1,2 | Shrub (<3m) | 1899 | California |
Lupinus polyphyllus | Russell lupin | 1,11 | Erect herb | 1958 | N America |
Lycium ferocissimum | boxthorn | 2 | Shrub (<3m) | 1897 | S Africa |
Melianthus major | Cape honey flower | Shrub (<3m) | 1878 | S Africa | |
Mimulus guttatus | monkey musk | 8 | Shrub (<3m) | 1878 | N America |
Myriophyllum aquaticum | parrot's feather | 12 | Aquatic | 1970 | S. America |
Nephrolepis cordifolia | tuber sword fern | Fern | 1974 | pantropic | |
Olea europaea subsp cuspidata | African olive | Tree (<6m) | 1977 | E Afr to S Afr | |
Osmunda regalis | royal fern | Fern | 1890 | Eur, W&S America | |
Oxylobium lanceolatum | oxylobium | 2 | Tree (<6m) | 1931 | W Australia |
Pandorea pandorana | wonga wonga vine | Vine | 1981 | N Guinea, E Australia | |
Paraserianthes lophantha | brush wattle | 1,2,3 | Tree (<6m) | 1870 | W Australia |
Paspalum distichum | Mercer grass | Grass | 1906 | Europe | |
Passiflora edulis | black passionfruit | 1,3 | Vine | 1950 | trop America |
Passiflora mixta | nthn banana passionfruit | 1 | Vine | 1970 | N Andes |
Passiflora mollissima | banana passionfruit | 1,12 | Vine | 1958 | trop S America |
Pennisetum clandestinum | Kikuyu grass | 1,2 | Grass | 1936 | E. Africa |
Pennisetum macrourum | African feather grass | Grass | 1940 | trop. & Sthern Africa | |
Pennisetum setaceum | African fountain grass | 1,12 | Grass | 1982 | NE Africa |
Phytolacca octandra | inkweed | 11 | Shrub (<3m) | 1867 | trop C&S America |
Pinus contorta | lodgepole pine | Tree (>10m) | 1957 | NW America | |
Pinus spp. incl mugo, contorta, pinaster, radiata | wilding pine | 1 | Tree (>10m) | various | |
Polygala myrtifolia | sweet pea bush | 1,2 | Shrub (<3m) | 1870 | S Africa |
Populus alba | white poplar | 11 | Tree (>10m) | 1904 | Eurasia. Africa |
Prunus avium | sweet cherry | Tree (6-10m) | 1872 | Europe | |
Pseudotsuga menziesii | Douglas fir | Tree (>10m) | 1925 | N America | |
Psoralea pinnata | dally pine | 2 | Shrub (3-5m) | 1870 | S Africa |
Pyracantha angustifolia | orange firethorn | 11 | Shrub (3-5m) | 1958 | China |
Reynoutria japonica | Japanese knotweed | 7 | Erect herb | 1935 | Japan |
Reynoutria sachalinensis | giant knotweed | 7 | Erect herb | 1935 | E Asia, N Japan |
Rhamnus alaternus | evergreen buckthorn | 2 | Shrub (3-5m) | 1940 | Mediterranean |
Rosa rubiginosa | sweet briar | 10,12 | Shrub (<3m) | 1867 | Europe |
Rubus fruticosus agg. | blackberry | 1,2 | Vine | 1867 | N temperate |
Rumex sagittatus | climbing dock | Vine | 1935 | S Africa | |
Salix cinerea | grey willow | 2 | Tree (6-10m) | 1925 | Eur, W Asia, N Africa |
Salix fragilis | crack willow | 2 | Tree (6-10m) | 1880 | Europe, W Asia |
Salvinia molesta | salvinia, water fern | 12 | Aquatic | 1964 | sub/tropical widely |
Sambucus nigra | elder / elderberry | Tree (>10m) | 1867 | Eur, W Asia, N Africa | |
Sedum acre | stone crop | Mat forming | 1904 | Eur, W Asia, N Africa | |
Selaginella kraussiana | selaginella | 11 | Fern | 1919 | C&S Africa |
Senecio angulatus | Cape ivy | 11 | Vine | 1940 | S Africa |
Senecio jacobaea | ragwort | 2 | Bi/Annual | 1894 | Europe, W Asia |
Senecio mikanioides | German ivy | 1,10 | Vine | 1870 | S Africa |
Senna septemtrionalis | buttercup bush | Shrub (3-5m) | 1965 | Mexico, C America | |
Setaria palmifolia | palmgrass | 1 | Erect herb | 1981 | India |
Solanum jasminoides | potato vine | Vine | 1958 | S Brazil | |
Solanum linnaeanum | apple of Sodom | 11 | Shrub (<3m) | 1883 | N Africa |
Solanum mauritianum | woolly nightshade | 3, 12 | Tree (<6m) | 1883 | S Brazil, Uruguay |
Solanum pseudocapsicum | Jerusalem cherry | 1 | Shrub (<3m) | 1935 | Eastern Sth America |
Sorbus aucuparia | rowan | 11 | Tree (>10m) | 1904 | Eurasia |
Spartina alterniflora | American spartina | Grass | 1965 | N. America | |
Spartina anglica | spartina | 2,12 | Grass | 1981 | England |
Spartina x townsendii | spartina hybrid | 2 | Grass | 1924 | England |
Stipa neesiana | Chilean needlegrass | 2 | Grass | 1940 | S. America |
Stipa trichotoma | nassella tussock | 1,3,12 | Grass | 1931 | S. America |
Syzygium australe | brush cherry | Tree (6-10m) | 1982 | Qld, NSW | |
Teline monspessulana | Montpellier broom | 2, 10 | Shrub (<3m) | 1872 | Meditrn, Asia Minor, Azores |
Tradescantia fluminensis | wandering Jew | 12 | Mat forming | 1916 | Brazil |
Tropaeolum majus | nasturtium | 1 | Bi/annual | 1883 | N. Andes |
Tropaeolum speciosum | Chilean flame creeper | Vine | 1958 | Chile | |
Tussilago farfara | coltsfoot | Erect herb | 1975 | Eur, N Afr, N&W Asia | |
Ulex europaeus | gorse | 1,2,12 | Shrub (3-5m) | 1867 | W Europe |
Vaccinium corymbosa | blueberry | Shrub (<3m) | 1988 | N America | |
Vinca major | periwinkle | 2 | Erect herb | 1870 | E&C mediterranean |
Watsonia bulbillifera | watsonia | 2 | Bulb herbs | 1895 | S Africa |
Zantedeschia aethiopica | arum lily | 2 | Bulb herbs | 1870 | Sth Africa |
Zizania latifolia | Manchurian rice grass | Grass | 1906 | Asia | |
Number of species: 164 |
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Weeds Recognized as Potential Problems in New Zealand (as of 1996) | ||||||
Botanical name | Common name | Growth form | year of naturalisation in NZ | Country/area of origin | country in which species is plant pest | notes |
Agave americana | century plant | 1869 | Mexico | Local weed - vegetatively spreads through dunes (Ewen Cameron 1996) Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). In Weed Control operational plan for Rangitoto, 1996. | ||
Albutilon darwinii x A. pictum | Chinese lantern | Shrub (<3m) | 1981 | cultivated hybrid | Invading forest edges & forms thickets. A few infestations looking very weedy. Possibly in lag phase. (Lisa Forester, 1996). Minor around Auckland (Ewen Cameron, 1996) | |
Andropogon virginicus | broomsedge | Grass | 1976 | N & C Am, W Indies | Hawaii, Australia | Dense cover in disturbed grassland/scrub. |
Arctotheca calendula | Cape weed | 1870 | Sth Africa | Widely distributed in NZ (Flora IV). Poisonous. Poor pasture weed, or in coastal, sandy situations (Ewen Cameron & Carol West 96) | ||
Asparagus densiflorus | bushy asparagus | Lord Howe Is. | Already naturalised in 3-4 places in Auckland (Ewen Cameron 1996) | |||
Azolla pinnata | ferny azolla | Aquatic | 1969 | trop. Africa, Asia, Australia | Floating fern. Has replaced a native floating fern Azolla rubra, over most of northern NZ (Ewen Cameron, 1996) | |
Banksia integrifolia | banksia | mid 1980s | Australia | First naturalised mid-1980's. Naturalised commonly by 90's. Threat to well drained sites, e.g. stabilised dunes. (Ewen Cameron, 1996) | ||
Bartlettina sordida | bartlettina | Shrub (<3m) | 1984 | Mexico | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Whangarei, Auckland, Lower Hutt - locally established as escape from cultivation (Flora IV). So far mainly forest margins where stands out at foreign (Ewen Cameron 1996) | |
Brachiairia mutica | para grass | 1977 | N&W trop. Africa | Listed as a weed for eradication on Raoul Island but not likely to have a long term significant impact. One patch - only known infestation in NZ. | ||
Bryonia dioica | white bryony | Soft vine. Spreading in Makino Scenic Reserve on the Rangitikei River (Wanganui). Only NZ record so far, but looks to be spreading (via birds). (Colin Ogle 1997) | ||||
Canna indica | Indian shot | 1870 | West Indies, C&S America | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Usually spreads vegetatively rather than by seed; problem where its been allowed to spread over long time period (Ewen Cameron 1996). | ||
Cardiospermum spp. | balloon vine | Vine | not yet | Aust, Sth Afr, Pacific | Not yet seen naturalised but cultivated widely. (Lisa Forester, 1996). Potential weed given overseas experience? (Ewen Cameron 1996). | |
Carex flacca | carnation sedge | 1883 | Europe, N. Asia, N. Africa | Serious problem in Travis wetland, Christchurch. Dense, smothering ground cover, excludes natives. Seed & rhizome. Potential wetland threat. Young plants distinctively blue-grey. (Melanie Newfield, 1996). Not yet a threat in Auckland area (Cameron 1996). | ||
Ceratophyllum demersum | hornwort | 1969 | cosmopolitan | Widespread in lakes, rivers or wetlands. Can be free-floating or rooted. (Chris Richmond, 1997) | ||
Cestrum nocturnum | queen of the night | 1980 | W Indies, C America | Naturalised in Auckland, Northland and BoP. Wasteland and scrub. Poisonous. Spreading into native bush where hard to distinguish from natives (Ewen Cameron 1996). Potential as serious eco. weed (Carol West 96) | ||
Cestrum parqui | green cestrum | Shrub (<3m) | 1908 | Warm temp S Am | Naturalised in one place in Auckland only & hard to kill (Ewen Cameron '96). Potential as serious ecological weeds (Carol West '96). Scrub, riparian. Frost resistant. Poisonous. | |
Clematis tangutica | Chinese clematis | 1958 | ? | In shrublands around the Clutha Valley, Otago, where it is spreading slowly. A potentially significant weed - should be watched (Colin Ogle, Brian Patrick, '97); Note: the species is probably C. tibetana (Colin Ogle) | ||
Crassula multicava | pitted crassula | 1959 | Sth Africa | Establishing northern coastal cliffs, Little Barrier, where it is very bad - potential nasty (Ewen Cameron 1996). Invades bare ground, rock. Spreads vegetatively to form dense cover - plantlets on flower heads drop off & develop. | ||
Cyathea cooperi | tree fern | Fern | 1993 | Hawaii | Cultivated in Auckland for 15 years. So far only one wild record (which is in the open). Hard to distinguish from natives - possible it might hybridise? (Ewen Cameron, 1996) | |
Cynodon dactylon | Indian doab | 1846 | Pantropical | Widespread grass in warmer parts of NZ; may be a threat in species places with rare, low-growing communities (Carol West). Minor problem back of beaches, but Kikuyu & buffalo grass far worse (Ewen Cameron 1996). | ||
Echium plantagineum | Paterson's curse | 1880 | Med nth to Sth England | Australia | Not really a threat to natural areas ? (Ewen Cameron 1996). Wasteland, pastures. Poisonous. North Is especially north of volcanic plateau. Rare in northern South Is. | |
Ehrharta longifolia | annual veld grass | Grass | 1989 | Sth Africa | Wanganui only. Annual (Sept to Nov.). Tufted; in gardens, sandy soils. (Colin Ogle, Wanganui Conservancy, 21/8/96) | |
Elodea canadensis | Canadian pondweed | 1916 | N America | C Eur, UK, NSW | Listed as naturalised in Auckland (Dick Veitch, 1995). Not a major problem in Auckland where Egeria is main pest (Ewen Cameron 1996); but suppresses natives in lakes/rivers where it has not been replaced by egeria (eg L. Waikaremoana) (Chris Richmond '97) | |
Equisetum hyemale | rough horsetail | Rhizomes to 1m underground. Toxic to stock. Aggressive & almost impossible to eradicate. Being sold & given away as medicinal herb. Slender asparagus-like spear with black rings. (Melanie Newfield, 1996). Major potential weed. | ||||
Eragrostis curvula | African love grass | Grass | 1969 | Africa | 1 m tall. Invading in Northland and Three Kings Islands. (Lisa Forester, 1996). Potential major weed (Carol West 1996). | |
Erythrina x sykesii | coral tree | 1986 | cultivated hybrid | Cuttings & dropped branches take root easily. Dense thickets can form. A major problem in wetlands of some Northland areas. Listed in Little Barrier Is. Weed control operational plan, 1996. However sterile, and easily controlled. (Forester, West, Cameron) | ||
Eucalyptus botryoides | blue gum | 1957 | d valign="top">New Sth Wales, Victoria | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Never seen gums as a major weed (Ewen Cameron 1996); but may just be seeing a very early lag phase (Carol West 1996). | ||
Eucalyptus globulus | Tasmanian blue gum | 1880 | Tasmania | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Never seen gums as a major weed (Ewen Cameron 1996); but may just be seeing a very early lag phase (Carol West 1996). | ||
Eucalyptus saligna | Sydney blue gum | 1957 | NSW, Queensland | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Never seen gums as a major weed (Ewen Cameron 1996); but may just be seeing a very early lag phase (Carol West 1996). | ||
Ficus macrophylla | Moreton Bay fig | Tree (>10m) | 1995 | Australia | Pollinator recently arrived in NZ. First seedling seen Auckland 1995. One to watch, but evidence suggests won't be as aggressive as F. rubiginosa (Ewen Cameron, 1996). | |
Ficus microcarpa | not yet see note | Not yet naturalised - still lacks pollinator. Occasionally cultivated in NZ. One to watch. (Ewen Cameron, 1996). | ||||
Ficus pumila | creeping fig | 1981 | Japan, China | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Can't set seed but can climb; not seen as a problem yet (Ewen Cameron 1996). | ||
Ficus rubiginosa | Port Jackson fig | 1981 | NSW, Queensland | Pollinator arrived 20 years ago. Potential pest only in special places, e.g. Rangitoto island. (Ewen Cameron, 1996) | ||
Furcraea foetida | Mauritius hemp | 1966 | S. America, Brazil | Being eradicated on Raoul Island as considered to be able to significantly affect indigenous community in long term. Also a problem on foreshore of Kawau Island, though can't spread quickly (Ewen Cameron 1996). | ||
Galeobdolon luteum | aluminium plant | 1988 | Europe, W. Asia | Can cover large areas of ground in open and semi-shaded areas. Listed in Little Barrier Is. Weed control operational plan, 1996. Spreads rapidly - one to watch (Ewen Cameron 1996). | ||
Glyceria maxima | reed sweetgrass | Aquatic | 1906 | Europe | Australia | Semi-aquatic grass; grows in slow moving streams, drains. (Carol West 21/8/96), and a major ecological weed in wetlands (Ewen Cameron 1996). Forms dense monoculture in fertile sites. Effective nutrient stripper in artificial wetlands. (Chris Richmond '97) |
Gunnera tinctoria | Chilean rhubarb | 1968 | Sth America (Andes) | Megaherb; planted widely in NZ. In wet places, seepages, riverbanks; & on wet/clay seacliffs. Very invasive along several km of banks of Oanui River, & spreading quickly in Wanganui region. (Colin Ogle 1997) | ||
Homalanthus populifolius | Queensland poplar | 1980 | NSW to New Guinea | Bird dispersed. Shade tolerant & invades broad range of habitats. (Lisa Forester, 1996). Major ecological weed (West, Cameron 1996). Common in Auckland city (Cameron 1996) | ||
Homeria collina | Cape tulip | 1944 | Sth Africa | Listed as class A noxious weed - but more as is toxic than for any environmental impacts (Ewen Cameron 1996). | ||
Houttuynia cordata var. chameleon | var. chameleon | Aquatic | Not yet. see note | Asian. | USA, Asia | Introduced 1990, not yet naturalised. A MAF notifiable plant. Ground cover; up to 1m tall; rhizomes. Seeds with or without fertilisation. Tolerates submerged or dry. (Paul Champion, NIWA, 14/8/96) |
Impatiens sodenii | shrub balsam | 1958 | E. Africa | Forms dense thickets. Grows well from seeds & cuttings. Listed in Little Barrier Is. and Rangitoto Is. Weed control operational plans, 1996. Potential to be bad eco. weed - is becoming more common on bush margins, rank grasses etc. (Ewen Cameron 1996). | ||
Imperata cylindrica var. major | cogon grass, bladey grass | Grass | 1911 | trop/warm temp Asia, Aust, New C., E. Afr, Lord Howe | Dense swards. (Lisa Forester, 1996) | |
Larix decidua | larch | 1919 | Europe, W Asia | Aggressive in the MacKenzie Basin (Shannel Courtney, DoC Nelson 21/8/96) and in Central Otago. | ||
Lythrum salicaria | purple loosestrife | Aquatic | 1958 | Eur, W Asia, Nth Afr | USA, Australia | Lake margin, wetland. Up to 3m. Each plant up to 50 stems. 2.5 million seeds/plant. Seeds viable up to 3 years. (Paul Champion, NIWA, 14/8/96) |
Malvaviscus arboreus var. arboreus | Turk's cap | 1981 | Trop & sub-trop Am | Shade tolerant. Spread by layering. (Inf.: Lisa Forester, DoC Northland, 14/8/96). Have seen fruit; potential significant weed (Ewen Cameron 1996). | ||
Miscanthus nepalensis | Himalayan fairy grass | Grass | 1946 | Nepal/India | Invading forest margins, bluffs. (Lisa Forester,1996). Large problem on open cliffs in Bay of Plenty; slowly increasing in Northland (Ewen Cameron 1996). | |
Myoporum insulare | Australian ngaio | 1978 | temp. Australia, Lord Howe Is | In Weed Control operational plan for Rangitoto, 1996. Large genetic risk as could hybridise with native species (Cameron, West 1996). | ||
Myrica faya | fire tree | not yet | Azores | Hawaii | Naturalised in Chatham Is; not yet seen naturalised mainland NZ, but cultivated widely in NZ. (Lisa Forester & Carol West 1996) | |
Ottelia ovalifolia | swamp lily | 1899 | Australia | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Fairly aggressive water weed (West 1996) | ||
Pandorea jasminoides | Bower vine | Vine | 1981 | Nth NSW, SE Qld | Controlled on Little Barrier. Capacity to smother up to mid-canopy. One plant can cover large area with runners. Matting effect in open. Only flowers/fruits in the sun. Fruiting appears rare in NZ.(L Barrier Weed Op. plan 1996). One to watch (West 1996). | |
Pennisetum purpureum | Elephant grass, Napier grass | Grass | post 1987 | Trop Afr. | Galapagos | BTAG trying to ban sale. Growing north of Kaitaia. (Lisa Forester,1996). Repro mainly vegetative. Tolerate range of conditions (0-500 m), but killed by frost. Drought resistant. |
Phoenix canariensis | Canary Island palm | pre 1980 | Canary Island | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Could be in early lag phase (West 1996). Frequently naturalised near adults; dioecious - should advocate only males are planted (Cameron 1996). | ||
Plectranthus ciliatus | plectranthus | 1975 | E and S Africa | Worst species of P. ciliatus, ecklonii, grandis group. | ||
Plectranthus ecklonii | plectranthus | Shrub (<3m) | 1978 | E and S Africa | Mainly spreads vegetatively. | |
Plectranthus grandis | plectranthus | Shrub (<3m) | 1988 | E Africa? | Most recent species of P. ciliatus, ecklonii, grandis group. | |
Podranea ricasoliana | Port St John creeper | 1981 | Sth Africa | Aggressive vine; layers (Ewen Cameron 1996) | ||
Pomatogeton | clasped pondweed | aquatic | Not yet. See note | Not yet naturalised. Rhizomes. Hybridises with other species in the genus. Identify by leaf surrounding stem. (Paul Champion, NIWA, 14/8/96) | ||
Pomatogeton crispus | curly pondweed | 1940 | Eurasia, Africa, N. Am, Australia | Looks native. Invades submerged aquatic plant communities & replaces native potamogeton & myriophyllum species. (Chris Richmond 1997) | ||
Prunus campanulata | Taiwan cherry | Tree (6-10m) | 1988 | East Asia | Increasing weed of forest (Cameron 1996). | |
Prunus laurocerasus | cherry laurel | Tree (<10m) | 1958 | SE Europe | Poisonous. Expanding range. (Lisa Forester,1996). Sparingly naturalised in Auckland (Cameron 1996). But naturalising in many parts of NZ - need more public awareness of this species (West 1996). | |
Prunus lusitanica | Portugal laurel | 1988 | Spain, Portugal, Azores | (Identified: Lisa Forester, DoC Northland, 14/8/96) | ||
Prunus serrulata | Japanese hill cherry | Tree (>10m) | 1982 | China, Japan | Growing profusely in catchments where it is established. Widely cultivated. (Lisa Forester, 1996) | |
Psidium cattleianum | purple guava | Shrub (3-5m) | 1977 | S Brazil | Raoul Is, Hawaii, Mauritius | Worth watching (see notes on impacts overseas). Identified for eradication in Raoul Island plan. |
Psidium guajava | yellow guava | Shrub (<3m) | 1965 | Trop America | Raoul Is, trop. Pacific | Forms solid thickets. Bird dispersed. (Lisa Forester, 1996). Intolerant of frost & deep shade. Waxy cuticle resists herbicides. Possibly too tropical a species to be a major weed on mainland NZ (Cameron 1996). Being eradicated on Raoul Is. |
Racosperma melanoxylon | Tasmanian blackwood | 1918 | E Aust, Tasmania | Sth Afr, Argentina, California | Invades disturbed forest. | |
Rhaphiolepsis umbellata | sexton's bride | Shrub (<3m) | 1982 | Japan, Korea | 6 months flowering, 6 months fruiting. Can invade poor soils so is a species to watch. (Ewen Cameron, 1996) | |
Rhododendron ponticum | rhododendron | Shrub (3-5m) | 1958 | SE Europe, Asia minor | UK, Ireland | Swamp. wetland, pakahi. Well established West Coast. Dark dense canopy. 12 years before seeding but prolific annual seed. Outbreeder. (Melanie Newfield, 1996). |
Ribes sanguineum | flowering currant | Shrub (<3m) | 1904 | West N America | Spreads readily in Southland (Carol West, 21/8/96) | |
Robinia pseudacacia | false acacia | 1870 | C& E Nth America | Eur, Mediterranean, Australia | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Forest margins. | |
Rorippa nasturtium-aquaticum | watercress | 1852 | Eurasia, N. Africa | Listed as naturalised ecological weeds in Auckland ( Dick Veitch, 1995). Usually in modified streams, but could be desirable to remove from some places (West 1996). | ||
Sagittaria montevidensis | arrowhead | 1996 | Nth & Sth America | 2m + tall. 100's seeds/flower. Buds off basal rhizome. Sold as pond plant since 1970's. Naturalised in one site. (Paul Champion, NIWA, 14/8/96). Potential major weed. | ||
Schinus terebinthifolius | Christmas berry | 1995 | S America | Australia, Florida, Hawaii, Norfolk Is, Mauritius | First naturalised Whangaroa 1995, 2nd seedling Mercer 1996. Allelopathic. Dioecious. Invades broad range of habitats, from mangrove to pinelands; esp disturbed habitats. (Ewen Cameron, 1996) Allelopathic. Casts deep shade, excludes understorey. | |
Spartium junceum | Spanish broom | 1940 | Mediterranean | In Weed Control operational plan for Rangitoto, 1996. | ||
Stenotaphrum secundatum | buffalo grass | 1872 | trop. America & Africa | Listed as naturalised ecological weeds in Auckland (Dick Veitch, 1995). Smothers coastal areas (Cameron 1996). | ||
Tecomaria capensis | Cape honeysuckle | 1958 | Sth Africa | Forms exclusive thickets in full sun and extends into shade, preventing regeneration. Seed is wind dispersed. (Listed in Little Barrier Is. Weed control operational plan, 1996) | ||
Thunbergia grandiflora | sky flower | Vine | Not yet. See note. | India | Australia, Singapore | Tropical vine. Not yet naturalised in NZ but a big problem in Australia. (Lisa Forester, 1996) |
Trachycarpus fortunei | Chinese windmill palm | Naturalised freely. ( Ewen Cameron, 1996). Proven to spread & establish mature trees in native forest. Controlled on Little Barrier. | ||||
Undaria pinnatifida | seaweed | Aquatic: marine | 1987 | Japan, Korea | Brown algae up to 1m+. First discovered Wellington harbour 1987. In 1996 recorded in Timaru, Oamaru, Port Chalmers, Lyttelton, Picton. Mod sheltered to 5 m below low water spring. | |
Utricularia gibba | bladderwort | Aquatic | 1980 | More wide ranging than native species. Rapidly spreading. Displaces natives. Resistant to sprays & difficult to remove. Forms mats. (Paul Champion, NIWA, 14/8/96) | ||
Number of species: 79 |