Green cestrum
Botanical Name
Cestrum parqui
Family
Solanaceae (nightshade)
Where is it originally from?
Chile and Peru
What does it look like?
Smelly shrub (<1-3 m), with erect stems that become woody as it matures. Hairless, alternate leaves (20-120 x 5-30 mm) are foul-smelling when bruised. Dense panicles of greenish-yellow tubular flowers (15-23 mm long) with petal margins bent backwards and which are fragrant at nighttime, appear from November to June, followed by glossy, purplish black berries (7-10 x 6-8 mm).
Are there any similar species?
Cestrum elegans, C. fasciculatum, C. nocturnum, C. aurantiacum and many native shrub species, eg. Mahoe, are similar.
Why is it weedy?
Produces many long-lived, widely dispersed seeds, and forms dense, shady masses. Prefers damp conditions, is moderate to highly shade tolerant, and grows in most soil types, and hot or cold conditions. Deadly poisonous, not grazed.
How does it spread?
Birds, flooding, soil movement and vegetation dumping.
What damage does it do?
Forms dense (occasionally pure) stands in forest understorey, preventing the establishment of native plant seedlings. Poisonous berries and rotting vegetation may affect native fauna.
Which habitats is it likely to invade?
Disturbed and open forest and margins, streamsides and shrublands, potentially throughout New Zealand.
What can I do to get rid of it?
Rare, report all sites to your regional council or local Department of Conservation office.
Hard to distinguish from many native species (apart from foul smell) so best controlled when in flower. Wear gloves when handling.
1. Pull out small plants (all year round), leave on site to rot down.
2. Cut down and paint stump (all year round): a product containing 100g picloram+300g triclopyr/L (100ml/L) or triclopyr 600 EC (100ml/L) or triclopyr 120g/L (500ml/L).
3. Spray (spring-summer): triclopyr 600 EC (30ml/10L) or triclopyr 120g/L (15ml/L).
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and directions for the purchase, use and storage of the product, are followed and adhered to.
What can I do to stop it coming back?
Stems resprout. Reseeds into bared areas. Exclude stock at all times. Replant bared sites to minimise regrowth. Check for seedlings 6-monthly.
Images
