What does it look like?
Woolly nightshade (also known as tobacco weed) is a shrub or small tree that can rapidly grow to 10 metres tall. It has large, greyish green leaves that are up to 25 cm long with an unpleasant, pungent (kerosene-like) smell when crushed. All parts of the plant are covered in dusty hairs. Clusters of purple flowers with yellow anthers turn to bunches of round yellow berries when ripened.
Why is it a problem?
Woolly nightshade grows rapidly and can displace native plants to form dense stands. It produces toxins that poison the soil to slow the growth of many other plant species, preventing the regeneration and establishment of native forest.
Woolly nightshade is adapted to a wide range of habitats, from coastal areas to inland forest, yet it rarely invades intact habitat. It is moderately shade tolerant, requires medium to high soil fertility and is tolerant of frost. Dense stands can invade pasture on poor soils, especially in hill country areas and impede livestock movement.
Woolly nightshade can flower and fruit at any time of the year, producing large numbers of viable seeds. Seedlings established in summer can bear flowers by the autumn. It can regrow when mechanically damaged by cutting or uprooting and pieces of root remaining in the soil will regrow.
All parts of the plant are thought to be toxic to livestock. The berries are moderately toxic to people, especially children. The leaves shed fine hairs when touched, which irritate the skin, eyes, nose and throat and in some cases cause trouble with breathing: handling it can cause irritation and nausea.
Control methods
If you think you have woolly nightshade on your property or have seen woolly nightshade, contact us first on 06 835 9200.
- Pull up all small plants (easiest in winter). Leave on site to rot down.
- Cut and paint stumps (all year round) using a product containing 100g picloram+300g triclopyr/L or triclopyr 600 EC (100ml/L) or picloram gel.
- Frilling (all year round) using a product containing 100g picloram+300g triclopyr/L (100ml/L) or triclopyr 600g/L (100ml/L) or triclopyr 120g/L (200ml/L).
- Injection method: use either 10 mm wide holes drilled at a 45-degree angle down into trunk, 50 mm deep spaced at 50 mm around the trunk, or a series of 80 mm wide blazes cut to a depth of 15-20 mm, spaced at 20-40 mm. Fill each with picloram gel.
- Spray using a product containing 100g picloram+300g triclopyr/L (25ml/10L) or triclopyr 600 EC (60ml/10L) or triclopyr 300 EC (12ml/L).
More information
Woolly nightshade is listed as a Progressive Containment pest in the Hawke’s Bay Regional Council and is subject to Plan Rule 5.
Woolly nightshade is known to occur in urban Napier, Havelock North, Hastings, Te Awanga, Haumoana and Clive as well as rural areas north of Napier including Patoka, Eskdale and Whirinaki.
Related links
https://agpest.co.nz/pest-directory/#weeds
http://www.nzpcn.org.nz/flora_details.aspx?ID=2790
http://www.nzflora.info/factsheet/Taxon/Solanum-mauritianum.html
https://www1.maf.govt.nz/uor-cgi/uor.pl/show?species_id=36738
https://www.weedbusters.org.nz/what-are-weeds/weed-list/woolly-nightshade/
Notify Council
If you think you've found this pest, please get in touch with our Biosecurity Team at biosecurity@hbrc.govt.nz or call us on 0800 108 838.
Management Programme
National Pest Plant Accord
All plants on MPI's National Pest Plant Accord (NPPA) are unwanted organisms under the Biosecurity Act 1993 whose formal or casual trade contributes significantly to their spread.
Plants on the Accord cannot legally be propagated, distributed, or sold in New Zealand. If allowed to spread further, these pest plants could seriously damage our economy and environment.
Progressive Containment Programme
There are a number of pests that are well established in the Hawke’s Bay region but their present infestation levels are still low enough for those levels to be reduced region-wide through a progressive containment programme. Progressive Containment programmes have the less specific aim of reducing levels of infestation within their respective management zones. While the general intent is to reduce these infestations to zero-levels at some time into the future, the primary focus of a progressive containment programme is to preventing a pest from spreading. For well-established pests whose harmful effects and spread can still be reduced, progressive containment offers the best ratio of cost to benefits.
The goal is to maintain a pest population at the lowest feasible level and confine it to a particular area while reducing numbers over time. In some cases this will result in fewer sites infested or in others the overall density of the pest will reduce over a 10 year duration period. Containment programmes usually target habitats of high ecological value that require protection and restoration.
Unwanted Organism
An unwanted organism is any organism that's capable of causing harm to natural or physical resources (like forests and waterways) or human health. A number of introduced pests in New Zealand are classed as unwanted.
More informationRules
Plan Rule 5
Except where an occupier of land has entered into a Written Management Agreement approved by Hawke's Bay Regional Council, an occupier of land shall;
a) destroy all apple of Sodom, Australian sedge, cotton thistle, Darwin's barberry, nassella tussock, saffron thistle, velvetleaf, and woolly nightshade plants on their land
b) destroy all Japanise honeysuckle plants on their land within the defined containment area
c) destroy all old man's beard plants on their land within the Kaweka and Ruahine Ranges buffer area and containment area.
Taxonomies
FamilySolanaceae
TypePlants
GroupTree
HabitatLand
Management ProgrammeNational Pest Plant AccordProgressive Containment ProgrammeUnwanted Organism
RulesPlan Rule 5
