Download pest plants - Marlborough District Council

PEST PLANTS
Wild ginger
Caution
Control
Plants in deep shade produce few or no
seeds, so begin control on margins to minimise
reseeding. Small infestations are best dug out;
ensure all rhizomes are dug out. Rhizomes
should be dried out and burnt, do not compost
as they can survive indefinitely. For larger
infestations cut stems off above pink ‘collar’ at the
base and make cuts on any exposed rhizomes.
Treat all cuts liberally with one of the following
herbicide mixtures:
Glyphosate (e.g. Roundup)
1 part per 4 parts water
Escort 1g per 1 litre water
The following herbicide mixture can be used as
an overall foliage spray if the infestation is too
large to cut and treat all the stems:
Escort
Knapsack 5g per 10 litres water
Disclaimer: Although this fact sheet has been produced in good
faith from a number of sources believed to be creditable, the
Marlborough District Council and/ or Department of Conservation
does not give any warranty that all information contained is
accurate or complete or that advice given will be appropriate in
all circumstances. The information regarding pesticides does
not necessarily appear on the labels of the products concerned,
therefore the Marlborough District Council and/ or Department
of Conservation shall not be liable to anyone in respect of any
damages suffered as a result of their reliance on the information
contained in this document. Mention of a product trade name
implies neither endorsement of those products nor criticism of
similar products not mentioned.
For more information on plant and animal pests phone:
Marlborough District Council (03) 520 7400
Department of Conservation Sounds
Area Office(03) 520 3002
Department of Conservation South
Marlborough Area Office (03) 572 9100
SURVEILLANCE
Pest Plants
Follow-up work will be required to ensure all regrowth is removed or sprayed. Seeds only survive
in the soil for 2-4 years so eradication is possible.
When using any herbicide please read the label
thoroughly to ensure that all instructions and
safety requirements are followed.
Hedychium gardineramum
and H. flavescens
Marlborough Region
Wild ginger Hedychium gardineramum and H. flavescens
Wild ginger
Hedychium gardineramum
and H. flavescens
Status
Both Kahili and yellow ginger are surveillance pest
plant in the Marlborough region. This means that the
Marlborough District Council is aware that this pest
poses a risk within Marlborough and is gathering
information on the distribution of this weed to
evaluate its future status. The Marlborough District
Council and/or Department of Conservation welcome
any information about the of this plant. Land
occupiers are encouraged to control infestations.
Both Kahili and yellow ginger are banned from sale,
propagation, distribution or commercial display.
Should you see this plant please report it to the
Marlborough District Council or Department of
Conservation.
Origin
Kahili ginger is a native of India, growing on the
lower slopes of the Himalayas, while yellow ginger
originates in Eastern India and Madagascar. Both
Description
Wild gingers are herbaceous perennial plants. This
means that their life-span is more than two years
and they do not accumulate woody tissue. It grows
from large, branching rhizomes (tuberous roots).
These rhizomes are up to 3.5cm in diameter, up to
10cm in height and produce vertical stems annually.
Beds of living rhizomes can form a dense layer up to
a metre thick. Adult stems reach a maximum height
of 2 metres and produce large wax covered, ovate
alternate leaves (20-45cm long x 10-15cm wide).
Yellow ginger leaves tend to be a little narrower
than Kahili ginger leaves. Individual Kahili ginger
flowers are lemon yellow with conspicuous red
stamens, and are grouped in large (12-45cm) flower
heads produced from February to April. Red seeds
(15-20mm long) are produced by Kahili ginger in
autumn and winter. Yellow ginger flowers are cream
to light yellow and come out in late autumn/ early
winter. The flowers are in smaller flower heads than
those of Kahili ginger. Yellow ginger flowers do not
produce seed. Wild ginger species prefer to grow in
open, light-filled environments which are warm and
moist, but will readily grow in semi and full shade
beneath the forest canopy. Maximum growth occurs
in spring and summer but plants go into a state of
semi-dormancy during the winter period.
Threat
Ginger forms dense clumps which spread
outwards, out-competing and displacing native
vegetation. It has the potential to be a major weed
in forest margins, native forest remnants, natural
open areas, roadsides and riverbanks. Wild ginger
spreads outwards along the ground by way of
rhizomes and new plants develop from rhizome
portions which detach from parent plant. Kahili
ginger seeds are spread by birds. The main source
of spread is by people illegally dumping ginger
rhizomes as garden waste on roadsides or in the
bush. It can grow in a wide range of conditions,
from full sun to total shade, good or poor drainage,
and is drought and frost tolerant once established.
Marlborough Region
types have been grown in NZ gardens since 1865,
but it was not until the 1940’s that Kahili ginger was
recorded in the wild. Wild ginger infestations exist
throughout the North Island with isolated infestations
in the South Island. Wild ginger is in numerous
gardens in Marlborough and is starting to escape
into the wild.