What does it look like?
Rampant, evergreen vine growing up to 8m tall with milky sap and twining flexible stems that are covered in down and woody near the base. Leaves are green, hairless and dull on the top, and downy and paler grey/green underneath with an arrowhead-like shape. Clusters of bell-shaped creamy coloured flowers, occasionally with pink streaks, appear from December to May, followed by distinctive thick, leathery, pear-shaped choko-like pods containing a dry white pulp, which splits open to disperse many black, thistledown-like seeds.
Why is it a problem?
Moth plant pods produce masses of viable seeds, from 250 to 1000 per pod, which germinate and grow rapidly in the light wells and semi-shade of established forests. The vines form large, heavy and long-lived masses which smother and kill host plants and prevent native species from establishing. Tolerant of a wide range of conditions and seeds can drift long distances (up to 30km) on air currents. The sap is an irritant.
What can we DO about it at Whangarei Heads?
Moth plant is easy to spot once in flower, and easy to control if no pods have formed. A large mass of vines and flowers can look daunting, but often can be traced down to just a few major vines, which can be hand pulled to remove the roots, or cut and stump treated. Removing just a few vines in this way can prevent thousands of seeds from being produced and spreading further.
How do I control it?
Additional safety note: Sap poisonous, causes dermatitis. Protect skin and eyes against contact with sap.
- Hand removal: Dig and pull out seedlings/small vines. Hang roots up off the ground, leave cut vines up in trees to die. Collect pods and dispose of to landfill, burn or bury deeply.
- Cut stump application: Cut at ground level and immediately treat cut stems with Gly/Met mix, or Cut ‘n’ Paste Met Gel. Leave remaining cut material on site to rot down.
- Foliar spray: in summer (2gms metsulfuron + 100 mls glyphosate mls /10 litres water + penetrant ), or (60ml Tordon Brushkiller® /10L water + penetrant), Summer-Autumn best. Clear off desirable trees before spraying to reduce non-target damage. Don’t replant sprayed sites for 6 months/until seedlings appear naturally.
- Spray seedlings with triclopyr @ 6mls/ L water + penetrant. Follow up regularly.
Remove and dispose of pods first to minimise seeding. Follow up regularly.
CAUTION: when using any herbicide or pesticide PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.
Get in touch with us at info@weedaction.org.nz if you would like some assistance in applying the above control techniques or equipment and herbicides to do so. We can supply any of the products or equipment needed, for free, thanks to support from Northland Regional Council.
