Priority weeds for volunteers to target in
Wellington City Council carries out some weed
control in Trelissick Park. However they need your help. There are a
few weed species which are best controlled by hand as long as the job
is done properly. This guide lists weeds in priority which you can help
control and guidelines on the best way to do this.
There are other
weeds in the park, less prevalent, some being controlled by Council
contractors, e.g. mile a minute, evergreen buckthorn, cotoneaster,
pampas, African clubmoss, Asiatic knotweed, gorse, daisy, boneseed,
banana passionfruit, bay, pasture grass. At the moment,
appears infrequently. However it has invaded many of the hillsides
Wellington and should be removed when found in the Park.
Remember if you see these weeds in the park and
easy to control now, they soon won't be!
A spreading groundcover which does not seed in New Zealand. Instead
this plant grows from stem fragments. This weed is an ecological
nightmare because it spreads as a thick carpet, preventing seedling
emergence. It also causes eczema in some dogs. Trelissick Park is well
used by dog walkers and we would like to keep it that way. To clear
tradescantia pull it out by hand or rake it into a compacted heap in
the shade on the ground (for bacterial action). A black plastic
covering stops spread from the heap. Otherwise, put all plant material
into a rubbish sack and carry out for the landfill. Try to get all
broken fragments and watch that you don't lose any into the stream
(this will only spread the problem).
Old Man's Beard:
This is becoming a serious problem in the park and adjoining areas. The
flowers are easily spread by wind, so it is important to tackle this as
soon as flowers appear, but before seeds are set early in the year. At
this time, OMB is easy to spot, as the white flowers are conspicuous.
It is useful to have another person to act as a 'spotter', because OMB
is sometimes hard to find in the thick bush. Cut the vines at ground
level and apply Vigilant or Triumph gel. Preferably pull down and bag
the vines for landfill disposal. Make sure all the vines are cut -
often hard to see in the surrounding scrub.
Climbing Asparagus: A nasty creeper which produces
small white flowers in early
summer, followed by orange berries which are spread by birds.
The tubers must be removed. It should be bagged and remove
for landfill disposal.
Japanese Honeysuckle: Most outbreaks have
controlled by Council contractors, but
outbreaks and re-growth still occur. Small plants can be pulled out,
otherwise cut at ground level and apply Vigilant or Triumph gel to the
Montbretia: Forms thick clumps which inhibit
seedling growth. Pull
out by hand, but make sure you get the corms, which can
be quite deep. If they don't all come out you can use a
trowel or an old chisel to dig them up. Leave the
remains exposed to the sun to kill off the corms, or
remove the corms from the park for landfill disposal
Buddleia: This shrub has attractive purple
flowers and can 'take over' areas, if
not removed. Pull out any seedlings you come across. For larger trees,
cut at ground level and apply Vigilant or Triumph gel to the cut
is an evergreen shrub/tree, which establishes quickly and displaces
native plants. Small wattle seedlings are widespread in the lower
part of the park. Pull these out by hand and expose to the sun.
Wattle seeds stay dormant in the soil for years, so this will
be an ongoing task Larger wattle trees can be cut to kill them.
They do not need poison.
is a large deciduous tree which produces 'helicopter seeds' that
are efficiently dispersed by wind. Pull out any seedlings
you come across. For larger trees, cut at ground level and
apply Vigilant or Triumph gel to the cut surface. They are
readily spotted by their orange leaf display in autumn.
Large deciduous trees, quickly distributed by birds. Pull out any
seedlings you come across. For larger trees, cut at ground level and
apply Vigilant or Triumph gel to the cut surface. They are readily
spotted by their orange leaf display in autumn.
After concerted efforts over recent years,
this has largely been eliminated from Trelissick Park streamside
areas. However, it can reinvade from seeds carried
down from upstream. It is best pulled out before
Outbreaks can be grubbed out. Otherwise, it can be lopped off at ground
level to give other plants a chance to take over.
Broom and Gorse:
These two yellow flowered shrubs are regular intruders into the Park.
Broom can be pulled out or cut and left
on the ground to rot. Poison is
Gorse is more prickly and also more difficult to
eliminate - needing Vigilant or
to poison the cut surfaces.
Convolvulus (Bindweed), Climbing Dock, Ivy:
These vines climb up and envelop young plants,
every summer. Cut away
the vines and free the plants. Climbing Dock and ivy should be bagged
and taken out for the landfill. Climbing Dock is especially hard to
control - with large tubers underground. Where time permits, these
tubers should be removed from the ground and from the Park.
Coastal Five Finger:
There is concern about the spread of Houpara or coastal five-finger
(Pseudopanax lessonii). This is indigenous in northern New Zealand but
hybridises with Lancewood (Pseudopanax crassifolius). We are trying to
rid the park of these invasive hybrids. Pull out or cut out any that
A native tree which is probably not endemic to the Wellington region.
It may replace the native vegetation of an area through aggressive
regeneration - especially areas recently cleared of tradescantia. For
this reason we encourage you to pull out karaka seedlings if they are
beginning to form a dense grove. This plant does supply fruit for
kereru and other birds so will not be completely removed.
Planted in the park historically to attract birds. We are leaving the
larger trees, for this reason, but pull out or cut any spread of
smaller tree lucerne.
Remember to keep piles of weeds clear of the
track, and out of the flood zone. If weeds end up in the stream they
Like many of Wellington's parks and reserves, a
common source of destructive weeds in Trelissick Park is from people
dumping their green-waste. Please don't contribute to the problem and
dispose of your green-waste thoughtfully.
The other important source of invasive weeds is
plants escaping from gardens and growing wild over the back fence. If
you live near a reserve such as Trelissick Park, please have a look in
your garden and have a think about plants that may become potential
weeds in the future. It doesn't take much for a fast-growing climber to
spread seed and escape into the native bush beyond your garden.