Black Nightshade (Solanum nigrum)

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Seedling black nightshade at ideal
time to spray
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Black nightshade just past an ideal time to spray (4 leaf)

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Mature black nightshade plant
showing seedheads

Black nightshade is an annual to short-lived perennial plant that has white or mauve flowers followed by berries that are first green, but change to black as they ripen. Mature plants can grow up to 75cm tall and flower between October and May. Well established plants become “bushy” as the main stem develops laterals. Leaves are pointed at the tip, expand in the middle and narrowing back to the leaf stalk. Leaf margins have a toothed appearance.

Black nightshade is found in arable land, disturbed pasture, gardens and waste areas throughout New Zealand, but is less abundant in the lower South Island. Although often mistaken for Deadly Nightshade, this species it is not considered poisonous to humans. Black nightshade is a problem in pea crops when the green berries are mistaken for peas during harvesting.

Control

Broadcast
Black nightshade is a common weed in young (new) pasture. Select* or MCPB Herbicides will provide grass and clover friendly control at the seedling stage, with useful suppression being achieved at later growth stages.

Pasture-Kleen* Xtra and Maestro can be applied to larger and actively growing plants if growing in established pasture. These two herbicides cause temporary suppression of clovers.

Use Rates
Select – 4L/ha (2-3 leaf stage)
MCPB – 6L/ha seedling stage)
Maestro – 1.5L/ha (actively growing weeds at the 3-6 leaf stage)
Pasture-Kleen Xtra – 2.0-3.0L/ha (actively growing weeds at the 3-6 leaf stage)

Fodder Brassicas
In fodder brassica crops, Radiate* herbicide provides excellent control of this yield suppressing weed without damaging your crop.

Spot Spraying
Spot spraying in established pasture can be undertaken with Tordon* Brushkiller XT. This herbicide is grass friendly, but will temporarily remove clovers from the sward.
Dow AgroSciences is currently undertaking trial work with T-MAX on Black nightshade and is showing good activity on this weed.

Tordon Brushkiller XT, T-MAX, Pasture-Kleen Xtra, Select and MCPB are registered pursuant to the ACVM Act 1997 No’s 3737, 7321, 7295, 5202, 268