Moth plant impacts in Northland
J J Dymock
For the Northland Regional
Council
The problem
• Vines strangle native
and roadside vegetation
• Large numbers of seed produced – 500/pod.
• Efficient wind seed dispersal – 20km
• High seed germination and germination success –
smothers native seedlings
• Seeds viable up to five years
• Poisonous, white, milky sap
• Thrives in warmer areas with moderate to high
rainfall
Moth plant habitats
•
•
•
•
•
•
•
•
•
Offshore island restoration projects
Mainland forest restoration and preservation
QEII and forest reserve sites
Roadsides
Amenity sites, urban parks and recreation sites
Orchard shelter belts
Lake margins
Home gardens
Plantation forestry
Moth plant has passed the lag phase
Feedback
• Since August 2011 – NRC website 1,185 page views in the Environment
section and 31 page views under Publications.
Kevin Matthews Bushland Trust, Kaitaia
• Moth plant is extremely difficult to deal with; it requires a long acting
Brush Killer herbicide which has the down side of nuking everything at
ground level it touches and most of the biodiversity with it.
• Regeneration from seedlings is a problem; seeds appear to have a long life
in the soil.
• Moth plant in pine plantation and orchards are obviously not suitable for
herbicide. Hand weeding is labour intensive and requires caution from
latex contact………esp. the eyes.
Nan Pullan QE II Trust, Whangarei
• Last season we dealt with a recently discovered infestation at Sandy Bay
and with several people we probably spent 12 hours x 2
Rod Brown Guardians of the Bay of Islands
• Moth Plant is a very bad weed indeed, probably the worst weed
around the BOI,of a field of strong contenders
• The private landowners on Motuarohia Island and Moturoa Islands
try to manage Moth Plant which blows onto all the islands from
Kerikeri Inlet or Russell and have been forced to use helicopter
spraying on the steep cliff faces. Long Bay at Russell is serious
source of wind blown seed.
• Moth Plant is to be found growing in every wind break in our area.
• I would strongly support any biological control which can be
introduced since we are fighting a losing battle and the
community groups are only dealing with a fraction of the problem
and have limited resources since they are also usually active in
pest control, planting and other environmental concerns.
Sara Brill – Northland Regional Council
I have one CPCA that we spent $4000 on herbicide for moth plant control from
2007-09. We spent money on some roadside work which included moth plant
in several areas. Estimate of $3-4,000 on it. We had 33 enquiries logged last
year for moth plant.
Barbara Parriss, Project Island Song, Bay of Islands
• Nice to know that there is finally some action on moth plant.
• Project Island Song weed busters have spent 600 hours (unpaid) on mothplant 2012-2014. It is the worst weed on the islands and is known from
Urupukapuka, Moturua, Motuarohia and Okahu.
• Kerikeri basin weed busters probably spent c. 20 hours (unpaid) on moth
plant during the same period.
• There are 2 mainland sites from which seeds can blow over to the islands:
west of Rawhiti along roadsides and particularly in an old pine plantation,
and at the southern end of Long Beach, Russell. A lesser site, but highly
visible, is on both sides of State Highway 10 between Puketona Junction and
the road to Kaikohe.
John Beacham – Waimate North Landcare Trust
• News that you are going for biocontrol is great as it is a tough one to
eliminate.
• Go for it , Cheers John