Silverleaf nightshade grows in summer. It grows in dense colonies and is very difficult to control.
Silverleaf nightshade is one of the most costly weeds for grain crop producers. It can:
Silverleaf nightshade contains toxic alkaloids. These are most concentrated in ripe fruit. Livestock poisoning is uncommon. Symptoms of poisoning include:
Silverleaf nightshade is upright and branched. It grows up to 60 cm tall.
Green berries as small as 7 mm can contain viable seeds. Plants produce up to 60 berries, each containing 10 – 210 seeds.
Interconnected root systems help give silverleaf nightshade its competitive ability and persistence.
Silverleaf nightshade looks like Quena, Western nightshade, and Brazilian nightshade.
Quena is shorter, only growing to 30 cm tall. It rarely has spines on the stems. It also has oval-shaped fruit, pale green unripe berries and shorter stamens (3.5 – 5 mm long).
Western nightshade is also shorter, only growing to 30 cm tall. It has spines on the leaves as well as stems. It’s fowers only have 4 petals and 4 stamens (3.5 – 5 mm long) and the fruit are cone-shaped with a small bump on the end.
Silverleaf nightshade grows in most parts of NSW. It is native to North America. It was first found in Australia in 1901 at Bingara on the north-west slopes of NSW.
Silverleaf nightshade grows on most soil types. Seedlings grow better in disturbed soil and germinate best:
The climate affects how silverleaf nightshade spreads. In summer rainfall areas silverleaf nightshade grows from seed and root segments. In winter rainfall areas it tends to grow more from root fragments.
Birds and livestock eat the fruit and spread the seeds. Seed can take up to 2 weeks to pass through the gut. About 10% of seed that passes through the digestive tract remains viable.
Seeds can also be spread by water and in contaminated grains and hay.
Cultivation breaks roots and machinery spreads them to new areas. Silverleaf nightshade can grow from root fragments as small as 1 cm. All parts of the root system can form shoot buds. If kept damp, root pieces can remain viable in the soil for up to 15 months.
Long-term control of silverleaf nightshade needs to consider that:
Controlling seedlings and seed set for 3 – 5 years reduces seed numbers in the soil.
To reduce the risk of moving silverleaf nightshade to clean areas:
Healthy spring and summer pastures compete with silverleaf nightshade during its growing season. Lucerne’s deep roots dry out the soil and limit silverleaf nightshade regeneration. In summer rainfall areas, perennial pastures provide the best competition.
Do not let livestock, particularly sheep, graze fruiting plants.
Avoid cultivating as it moves root pieces to clean areas.
Slashing does not control silverleaf nightshade. It recovers quickly, even in drought. Berries can grow close to the ground below the slash height.
The are no biological control agents in Australia.
Some plants release chemicals from their roots that inhibit other species. This is called allelopathy. Some Eucalyptus trees may be allelopathic to silverleaf nightshade. The most promising have been Eucalyptus brokwayi (Dundas mahogany), E. dundasii (Dundas blackbutt), E. spathulata (Swamp mallet) and E. salubris (Gimlet gum). These trees gave good control to just outside their drip lines.
Spot spray small infestations. Cover all above ground parts with herbicide. Repeat sprays are necessary.
Spray:
Do not spray when plants are stressed or dormant.
See Using herbicides for more information.
2,4-D 300 g/L + Picloram 75 g/L
(Tordon® 75-D)
Rate: 650 mL in 100 L of water
Comments: Spot spray. Spray to wet thoroughly. Extend treated areas beyond the last plant for 1 m.
Withholding period: Do not graze or cut crops (except sugar cane 8 weeks) or pastures for stock food for 7 days after application.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
2,4-D 300 g/L + Picloram 75 g/L
(Tordon® 75-D)
Rate: 15.0 L/ha
Comments: Boom spray. Apply at early flowering before berry set.
Withholding period: Do not graze or cut crops (except sugar cane 8 weeks) or pastures for stock food for 7 days after application.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
Fluroxypyr 333 g/L
(Starane™ Advanced)
Rate: 300 mL in 100L of water
Comments: Delay applications till majority of shoots have emerged. Follow-up treatment will be required
Withholding period: Do not graze failed crops and treated pastures or cut for stock food for 7 days after application. See label for more information.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
Glyphosate 360 g/L
(Various products)
Rate: 2.0 L in 100 L of water
Comments: Apply at early flowering to berry set stage, spray thoroughly to wet. Use only with good soil moisture conditions.
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate
The content provided here is for information purposes only and is taken from the Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.
Area | Duty |
---|---|
All of NSW | General Biosecurity Duty All pest plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable. |
All of NSW |
Prohibition on certain dealings
Must not be imported into the state, sold, bartered, exchanged or offered for sale. |
Central Tablelands
Contain recorded populations across the Central Tablelands region. Goal will be to contain silverleaf nightshade spread across the whole region with focus on spread or potential spread into production areas. |
Regional Recommended Measure* (for Regional Priority - Containment)
Whole of region: Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
Hunter |
Regional Recommended Measure* (for Regional Priority - Eradication)
Notify local control authority if found. Land managers should eradicate the plant from the land and keep the land free of the plant. A person should not deal with the plant, where dealings include but are not limited to buying, selling, growing, moving, carrying or releasing the plant. |
Murray |
Regional Recommended Measure* (for Regional Priority - Asset Protection)
Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
North West |
Regional Recommended Measure* (for Regional Priority - Asset Protection)
Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
Northern Tablelands
An exclusion zone is established for all the lands in the region, except the core infestation area comprising lands within the: • Inverell Shire Council in the Nullamanna and Delungra area. |
Regional Recommended Measure* (for Regional Priority - Containment)
Whole of region: Land managers mitigate the risk of new weeds being introduced to their land. Within exclusion zone: Land managers should eradicate the plant from the land and keep the land free of the plant. A person should not deal with the plant, where dealings include but are not limited to buying, selling, growing, moving, carrying or releasing the plant. Notify local control authority if found. Within core infestation: Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
South East |
Regional Recommended Measure* (for Regional Priority - Eradication)
Land managers should mitigate the risk of the plant being introduced to their land. Land managers should eradicate the plant from the land and keep the land free of the plant. A person should not deal with the plant, where dealings include but are not limited to buying, selling, growing, moving, carrying or releasing the plant. Notify local control authority if found. |
Western |
Regional Recommended Measure* (for Regional Priority - Asset Protection)
Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land A person should not buy, sell, move, carry, or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
*To see the Regional Strategic Weeds Management Plans containing demonstrated outcomes that fulfil the general biosecurity duty for this weed click here |
Reviewed 2023