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 (NPPA)
The NPPA is designed to prevent the sale, distribution and propagation of a set list of pest plants (the Accord list) within New Zealand. If allowed to spread further, these pest plants could seriously damage the New Zealand economy and environment.
More informationProgressive Containment Programme
To contain or reduce the geographic distribution of the subject, or an organism being spread by the subject, to an area over time.
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.
Rules
Rule 5 - Woolly Nightshade
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 destroy all [NAME] plants on their land.
Taxonomies
FamilySolanaceae
TypePlants
GroupTree
HabitatLand
Management ProgrammeNational Pest Plant Accord (NPPA)Progressive Containment ProgrammeUnwanted Organism
