Woolly nightshade
Solanaceae - Solanum mauritianum

What does it look like?

Woolly nightshade is a shrub or small tree that can rapidly grow to 10m tall. It has large, grey-green leaves that are up to 25cm long and are covered in felt-like hairs.  The leaves have an unpleasant, pungent (kerosene-like) smell when crushed. It produces purple flowers with yellow centres and bunches of yellow berries when ripened.

Woolly nightshade is adapted to a wide range of habitats. It can invade forest margins, disturbed forest, light gaps within forest, shrublands, riparian margins, estuarine margins, consolidated sand dunes, wetlands and urban areas. It rarely invades intact habitats. Can also be problemtic along roadsides and exotic forest margins.

Why is it a problem?

Woolly nightshade grows very rapidly and can crowd-out or shade-out native plants to form dense stands. It also effectively poisons the soil to inhibit or prevent the establishment of other less hardy species, including native plant seedlings. This has the effect of preventing the regenration/establishment of native forest. 

This plant is moderately shade-tolerant, tolerant to frost and requires medium to high soil fertility. Dense stands can ivade pasture on poor soils, especially in hill country areas and impede livestock movement. All parts of the plant are thought to be toxic to livestock.

Woolly nightshade can flower and fruit at any time of the year, producing large numbers of viable seeds.  Even very young plants can produce seed, for example, seedlings established in summer can bear flowers by the autumn. It also spreads vegetatively when mechanically damaged by cutting or uprooting and pieces of root remaining in the soil will regrow.

The berries of woolly nightshade are also moderately toxic to people (especially children) and they may be poisonous to livestock. The leaves shed fine hairs when touched, which irritate the skin, eyes, nose and throat, and in some cases cause trouble with breathing.

Control Methods

Physical control

  • Pull out small plants and leave on site for roots to dry and rot. This is easiest in winter.

Herbicide control

  • Drill and fill: drill 10 - 12 mm holes 200mm around the trunk.  Fill each with undiluted glyphosate.
  • Cut and squirt (all year round): make cuts at regular intervals around the trunk, apply 25ml Tordon Brushkiller per 1L water.
  • Cut and paint stumps (all year round): Tordon Brushkiller or triclopyr 600 EC (100ml/L) or Vigilant gel.
  • Frilling (all year round): 25ml Tordon Brushkiller per 1L water or 100ml triclopyr (600 g/L) per 1L water or 200ml Yates Woody Weedkiller per 1L water.
  • Spray: 25ml Tordon Brushkiller per 10L water or 60ml triclopyr (600 EC) per 10L water.

CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.

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