beautiful but dangerous - durban but dangerous ... new weed & invader plant legislation ... aloe...
TRANSCRIPT
Beautiful But DangerousInvasive Alien Plants of Durban
with some Indigenous Alternatives
Beautiful But DangerousInvasive Alien Plants of Durban
and the Eastern, Sub-tropical Region of South Africa
with some Indigenous Alternatives
Durban Unicity
Key
Category 1
Category 2
Category 3
No Category
Biocontrol
Poisonous
Herbicide
Note: category numbers areshown on each panel
Note: HERBICIDES may beused to control mostplants, but this is onlyshown for those speciesfor which chemicalshave been registered. BIOCONTROL optionsare shown only forspecies where biocontrolis effective.
Durban Unicity
New Weed & Invader Plant Legislation
By the year 2000, 10 million hectares of land in SouthAfrica had been invaded by alien plants. Alien plantshave numerous impacts:
!They can increase flood damage.!They compete with agricultural crops.!They displace indigenous plants and animals.!They increase the loss of water from catchments.!They increase the severity of fires.!They expand the range of disease-causing organisms.
Despite raising almost R 1 billion to date throughnational government programmes and working atunprecedented levels, we are not reducing the extentof the invasion. In recognising the threats posed byinvasive plants, the national Department of Agriculturehas drafted regulations and listed weeds and alien
invader plants under the Conservation of AgriculturalResources Act.
The list contains about 200 plants grouped into threecategories:
Weeds which may not be grown andmust be controlled.
Invader plants with commercial or utilityvalue, which may only be grown with a
permit under controlled circumstances.
Invader plants, which have amenity valueand which may be grown, but not plant-
ed, propagated, imported or traded. You may notgrow Category 3 plants within 30 metres of water-courses and the Department may instruct you to con-trol Category 3 plants in other areas.
Category 1
Category 2
Category 3
This Poster’s Objective
Prevention of alien plant invasions is farcheaper than control or eradication.
This poster profiles some of the most aggres-sive weed and invader plants in the DurbanUnicity area. Another poster in the seriescovers problem plants that are often used inhorticulture.
The plants on this poster were selected usingthese criteria:!They have or are expected to invade largeparts of Durban and are likely to do so inother sub-tropical parts of South Africa.!They are potential transformers of naturalhabitats.
Control and Eradication
In practice a combination of mechanical, chemical andbiocontrol methods are used to combat alien plants.However, where infestations are light or cover relativelysmall areas, control is best achieved by mechanicalmeans. Tackle light infestations first and then denserinfestations.
Small plants may be pulled out at the roots especiallywhen the soil is moist. Larger plants may need to bedug out at the roots. The secret to success is to tacklethe job in a planned way and to diligently follow-up toremove seedlings and regrowth.
For more serious problems herbicides and/or biologicalcontrol, using natural predators or pests, may be used. Itis recommended that professional advice is soughtbefore using these methods.
Pearl Acacia (grey) and Triffid Weed (palegreen) stand out on a slope dominated by weeds.Each Triffid Weed plant produces over a millionseeds a year and the species is coastal KZN'sworst weed.
Water Hyacinth covers the water at Clairwood Quarry.Water Hyacinth can double its mass every 18 days aswell as produce over 5 000 long-lived seeds from eachflower spike.
South Africa has spent more than R 1 billion on nationalalien plant control and eradication programmes and isstill not reducing the extent of the problem.
Yellow Bells tree with saplings escaping cultiva-tion. A global survey of 1060 plant invasionsfound that in 59 % of the cases horticulture wasthe source.
Extent of the Problem
Acacia longifolia Long-leaved Wattle
Origin: AustraliaShrub/Tree
Indigenous alternatives:Euclea racemosa
Bush GuarriPodocarpus latifolius
Real YellowwoodSapium integerrimum
Duiker-berry
Ageratum conyzoides andhoustonianumInvading Ageratum andMexican Ageratum
Origin: South and CentralAmerica respectivelyHerb
Indigenous alternatives:Tetraselago natalensis Natal Blue HazeVernonia capensis
Narrow-leaved VernoniaVernonia natalensis Silver Vernonia
Achyranthes aspera Burweed
Origin: Africa? now PantropicalHerb
Indigenous alternatives:Asystasia gangetica
Creeping FoxgloveHypoestes forskaolii
White Ribbon BushJusticia betonica
Paper Plume
Category 1
Category 1
Category 1
Above left:A. conyzoidesAbove right:A. houstonianum
Arundo donaxGiant or Spanish Reed
Origin: MediterraneanReed
Indigenous alternatives:Miscanthus capensis
East-coast Broom GrassPhragmites australis
Common ReedTypha capensis
Bulrush
Azolla filiculoidesRed Water Fern
Origin: North, Central and South AmericaFloating Fern
Indigenous alternatives:Ludwigia stolonifera
Creeping LudwigiaTrapa natans
Water ChestnutUtricularia inflexa
Bladderwort
Albizia lebbeckLebbeck Tree
Origin: Tropical AsiaTree
Indigenous alternatives:Acacia sieberiana
Paperbark ThornAlbizia adianthifolia
Flat-crownAlbizia versicolor
Large-leaved False-thorn
Category 1
Category 1
Category 1
Caesalpinia decapetalaMauritius Thorn
Origin: Europe and AsiaShrub/Scrambler
Indigenous alternatives:Acacia kraussiana
Coast Climbing ThornAdenopodia spicata
Spiny Splinter BeanCaesalpinia bonduc
Grey Nickernut Creeper
Cardiospermum grandiflorumBalloon Vine
Origin: TropicalAmericaClimber
Indigenous alternatives:Clematis brachiata
Traveller's JoyJasminum angulare
Wild JasmineRhoicissus rhomboidea
Glossy Forest Grape
Category 1
Category 1
Cestrum laevigatumInkberry
Origin: South AmericaShrub/Tree
Indigenous alternatives:Kraussia floribunda
Rhino-coffeePeddiea africana
Poison OlivePsychotria capensis
Black Bird-berry
Category 1
Chromolaena odorataTriffid Weed
Origin: Central and South America
Shrub/Scrambler
Indigenous alternatives:Chrysanthemoides monilifera
Bush-tick BerryPeristrophe cernua
False BuckwheatTecoma capensis
Cape Honeysuckle
Above: Young plants
Category 1
Eichhornia crassipesWater Hyacinth
Origin: South and Central AmericaFloating Plant
Indigenous alternatives:Nymphaea lotus
White WaterlilyNymphaea nouchali
Blue WaterlilyNymphoides thunbergiana
Small Yellow Waterlily
Lantana camaraTickberry/Lantana
Origin: Central and SouthAmericaShrub/Scrambler
Indigenous alternatives:Chrysanthemoides monilifera
Bush-tick BerryPeristrophe cernua
False BuckwheatPlumbago auriculata
Plumbago
Category 1
Category 1Above: examples of three colour forms
Montanoa hibiscifoliaTree Daisy/Montanoa
Origin: Central AmericaShrub/Tree
Indigenous alternatives:Dombeya burgessiae
Pink Wild PearRothmannia globosa
September BellsXylotheca kraussiana
African Dog-rose
Litsea glutinosaIndian Laurel
Origin: Tropical AsiaTree
Indigenous alternatives:Bridelia micrantha
MitzeeriProtorhus longifolia
Red BeechTrichilia dregeana
Forest Mahogany
Myriophyllum aquaticumParrot's Feather
Origin: South AmericaAquatic Plant
Indigenous alternatives:Ludwigia stolonifera
Creeping LudwigiaSium repandum
Water ParsnipTrapa natans
Water Chestnut
Category 1
Category 1
Category 1
Nerium oleanderOleander
Origin: MediterraneanShrub/Tree
Indigenous alternatives:Acokanthera oblongifolia
Dune Poison-bushBauhinia galpinii
Pride-of-De KaapBrachylaena discolor
Coast Silver Oak
Category 1
Opuntia monacanthaDrooping Prickly Pear
Origin: South AmericaSucculent Shrub
Indigenous alternatives:Aloe arborescens
Krantz AloeCrassula ovata
Kerky-bushPortulacaria afra
Porkbush
Pereskia aculeataBarbados Gooseberry/Pereskia
Origin: South and Central AmericaClimber
Indigenous alternatives:Acacia kraussiana
Coast Climbing thornCombretum bracteosum
Hiccup Nut Podranea ricasoliana
Port St John's Creeper
Category 1
Category 1
Pistia stratiotesWater Lettuce
Origin: South AmericaFloating Plant
Indigenous alternatives:Nymphaea nouchali
Blue WaterlilyNymphoides thunbergiana
Small Yellow Waterlily Trapa natans
Water Chestnut
Salvinia molestaKariba WeedOrigin: South AmericaFloating Fern
Indigenous alternatives:Ludwigia stolonifera
Creeping LudwigiaLudwigia palustris
Marsh LudwigiaNymphoides thunbergiana
Small Yellow Waterlily
Psidium guineense andPsidium X durbanensis
Brazilian and Durban Guavas
Origin: Tropical America and South Africa respectivelyShrub/Tree
Indigenous alternatives:Eugenia natalitia
Common Forest MyrtleLagynias lasiantha
Natal MedlarVangueria infausta
Wild Medlar
Category 1
Category 1
Category 1
Young plants
Above: P. guineenseLeft: P. guineenseRight: P. X durbanensis
Category 3
Schinus terebinthifoliusBrazilian Pepper TreeOrigin: South AmericaTree
Indigenous alternatives:Apodytes dimidiata
White PearAllophylus natalensis
Dune False CurrantBrachylaena discolor
Coast Silver Oak
Category 1
Solanum mauritianum BugweedOrigin: South AmericaShrub/Tree
Indigenous alternatives: Buddleja saligna
False OliveBuddleja salviifolia
Sagewood Solanum giganteum
Healing-leaf Tree
Sesbania puniceaBrazilian Glory Pea/ Red SesbaniaOrigin: South AmericaShrub
Indigenous alternatives:Erythrina humeana
Dwarf Coral TreeMundulea sericea
Cork Bush Tephrosia grandiflora
Large Pink Tephrosia
Category 1
Category 1
Tecoma stansYellow BellsOrigin: Tropical AmericaTree
Indigenous alternatives:Ochna natalitia
Natal Plane Peltophorum africanum
Weeping Wattle Thespesia acutiloba
Wild Tulip Tree
Category 1
Tithonia diversifolia Mexican SunflowerOrigin: Central AmericaShrub
Indigenous alternatives:Berkheya speciosa
Showy ThistleEuryops tysonii
Tyson's Resin Bush Chrysanthemoides monilifera
Bush-tick Berry
Acacia mearnsiiBlack WattleOrigin: AustraliaTree
Indigenous alternatives:Acacia robusta
Brack ThornAcacia karroo
Sweet ThornAcacia caffra
Common Hook Thorn
Category 1
Category 2
Casuarina cunninghamiana BeefwoodOrigin: AustraliaTree
Indigenous alternatives:Brachylaena discolor
Coast Silver OakDodonaea viscosa
Sand Olive Psydrax obovata
Quar
Category 2
Casuarina equisetifoliaHorsetail TreeOrigin: PantropicalTree
Indigenous alternatives:Brachylaena discolor
Coast Silver OakDodonaea viscosa
Sand OlivePsydrax obovata
Quar
Eucalyptus grandis Saligna GumOrigin: AustraliaTree
Indigenous alternatives:Olea woodiana
Forest OliveSyzygium cordatum
Umdoni Syzygium guineense
Water Pear
Category 2
Category 2
Populus X canescens Grey PoplarOrigin: Europe and AsiaTree
Indigenous alternatives:Brachylaena discolor
Coast Silver OakTerminalia sericea
Silver Cluster-leafTarchonanthus camphoratus
Wild Camphor Bush
Leucaena leucocephala LeucaenaOrigin: Tropical AmericaShrub/Tree
Indigenous alternatives:Acacia karroo
Sweet ThornSesbania sesban
River BeanTrema orientalis
Pigeonwood
Pinus elliottii Slash PineOrigin: North AmericaTree
Indigenous alternatives:Podocarpus falcatus
Common YellowwoodPodocarpus latifolius
Real Yellowwood
Category 2
Category 2
Category 2
Psidium guajavaGuavaOrigin: Tropical AmericaShrub/Tree
Indigenous alternatives:Eugenia natalitia
Common Forest MyrtleLagynias lasiantha
Natal MedlarVangueria infausta
Wild MedlarCategory 2
Acacia podalyriifoliaPearl AcaciaOrigin: AustraliaShrub/Tree
Indigenous alternatives:Brachylaena discolor
Coast Silver OakTarchonanthus camphoratus
Wild Camphor BushTerminalia sericea
Silver Cluster-leaf
Ricinus communisCastor-oil BushOrigin: Tropical AfricaShrub/Tree
Indigenous alternatives:Cussonia nicholsonii
Natal Coast Cabbage TreeDombeya burgessiae
Pink Wild Pear Dombeya tiliacea
Forest Wild Pear
Category 3
Category 2
Morus albaWhite or Common MulberryOrigin: AsiaTree
Indigenous alternatives:Croton sylvaticus
Forest Fever-berryFicus sur
Broom Cluster FigTrimeria grandifolia
Wild Mulberry
Melia azedarachSyringaOrigin: AsiaTree
Indigenous alternatives:Bersama lucens
Glossy White AshEkebergia capensis
Cape AshTrichilia dregeana
Forest Mahogany
Senna didymobotryaPeanut Butter CassiaOrigin: AfricaShrub
Indigenous alternatives:Bauhinia tomentosa
Bush Neat's FootCalpurnia aurea
Natal Laburnum Crotalaria capensis
Cape Rattle-pod
Category 3
Category 3
Category 3
Pennisetum purpureum Elephant Grass/Napier FodderOrigin: Tropical AfricaTall Grass
Indigenous alternatives:Cymbopogon spp.
Turpentine GrassesMiscanthus capensis
East-coast Broom GrassPhragmites australis
Phragmites Reed
Partners in Publishing - June 2001
Useful Contacts
For advice and planning of control work:! Plant Protection Research Institute, Cedara, runs a shortcourse on "Alien Plant Control for Land Managers". Tel: 033-355 9416 or 033-355 9413. E-mail: [email protected]! Your local District Conservation Officer, KZN Wildlife.Tel: 031-764 3515. E-mail: [email protected] ! The Ecological Advice Division, KZN Wildlife,Pietermartizburg. Tel: 033-845 1999.! Alien Buster Campaign, Toll-free line: 0800 005 376.
For information about the use of herbicides contact:! The Plant Protection Research Institute, Cedara. See abovefor details. Also http://www.nda.agric.za
For information about the use of biocontrol contact:! The Plant Protection Research Institute, Pretoria. Tel: 012-329 3269 or 012-329 3770.
E-mail: [email protected] find indigenous plants and professional contractorswho remove alien plants:! The Botanical Society - KZN Coastal Branch. Fax: 031-201 9958. E-mail: [email protected]! The Wildlife and Environment Society of South Africa(WESSA) - KZN Region. Tel: 031-201 3126. E-mail: [email protected]! Natural Areas Section, Durban Parks Department. Tel: 031-312 4466. E-mail: [email protected]! or visit these web sites:
http://www.wildlifesociety.org.za http://environment.durban.gov.zahttp://parks.durban.gov.za http://www.botanicalsociety.org.za
For Law Enforcement:! National Department of Agriculture, Directorate: AgriculturalLand and Resource Management, Box 345, Pietermaritzburg,3200. Tel: 033-345 3515 or 033-345 3557.
Useful References! Botha, C. and Botha, J. Bring Nature Back to Your Garden. A
WESSA Handbook with a chapter on alien weeds and lots of sugges-tions for indigenous alternatives.
! Conservation of Agricultural Resources Act, 1983 (Act No. 43of 1983)
! Guiding Principles for the Landscaping of the Durban InnerCity and KwaZulu-Natal Coastal Belt. A Durban Metro publica-tion available from the cashier at the City Engineer’s Building, 166 OldFort Rd, Durban.
! Grobler, H et al. A guide to the Use of Herbicides. 17th edition.Available from the National Department of Agriculture, Directorate:Communication, Pvt Bag X144, Pretoria, 0001.
! Henderson, L. Alien Weeds and Invasive Plants. Published by thePlant Protection Research Institute of the Agricultural ResearchCouncil, Pretoria.
! Moore, J. Eradicating Invading Alien Plants in KwaZulu-Natal.This is a cheap and useful publication available from WESSA at 100 Brand Rd, Glenwood, Durban.
! Olckers, T. et al. Biological Control of Weeds in South Africa(1990-1998). African Entomology. Memoir No. 1. EntomologicalSociety of Southern Africa.
AcknowledgmentsThe production of this resource was a joint effort betweenthe Durban Unicity Environmental Management Branchand Parks Department, the Wildlife and EnvironmentSociety of SA, and the Botanical Society of SA.
With additional assistance from:
! Lesley Henderson of the Plant Protection Research Institute,Agricultural Research Council.
! Geoff Nichols, Richard Symmonds, Penny Croucamp and RichardBoon who supplied photographs.
Copies of this poster are available from:
! Durban Unicity Environmental Management Branch, Developmentand Planning Building, 166 Old Fort Rd, Durban. Tel: 031-3002517.
! Durban Botanic Gardens, Information Centre, 9A Sydenham Rd,Durban. Tel: 031-201 1303
! Wildlife and Environment Society of SA, 100 Brand Rd,Glenwood, Durban. Tel: 031-201 3126.
! Botanical Society of SA. Fax: 031-201 9958.