Gorse Control Guide
Page Content
Do's and Don'ts of gorse control

Do's
- Plan your control program, this will save time and money in the long-run;
- Use a combination of different control methods;
- Consider the impact of your control methods on off-target things, especially if herbicides are used;
- Ensure machinery and equipment is washed down between sites or prior to contractors leaving site;
- Revisit the site and use follow-up treatments over at least 5 years;
- Coordinate your control program with neighbouring landholders where your gorse problem crosses property boundaries;
- For large infestations, tackle the smaller, outlying patches first. The larger infestation can be tackled later.
Don'ts
- Don't introduce gorse to gorse-free areas (e.g. by failing to wash down machinery and equipment between sites);
- Don't start your control program without first planning your approach;
- Don't rely on just one control method;
- Don't rely on one attempt at removal - follow-up is essential;
- Never burn gorse without follow up treatment of regrowth;
- Don't burn gorse in or next to native vegetation.
Spread of gorse
- Gorse reproduces by
seed; each plant produces huge numbers of seeds with a water-resistant
coating which allows them to remain dormant in the soil for up to 30
years.
- Seeds are usually released in hot or dry conditions but
can be stimulated into germination following burning or mechanical
disturbance. Most seeds fall around the parent plant but the pods can
split open and shoot seeds for a distance of up to 5m, allowing
infestations to spread rapidly.
- Gorse can also spread from seed
movement in water, soil, machinery and footwear. Individual gorse bushes
can live for up to 30 years.
- See the
Washdown Guidelines for Weed and Disease Control for detailed information on how to wash-down equipment and personnel to reduce the chance of spreading gorse.
Avoiding the introduction of gorse
- Preventing
the introduction of gorse to gorse-free areas is the best means of
control. Good machinery and equipment hygiene-practices are vital.
- Gorse
seed is usually carried into new areas in soil and mud attached to
machinery or boots. Gorse seed is too heavy to be dispersed by wind, and
birds are not important in spreading seed.
- Gorse seed can also
be carried in water. Removing gorse bushes on the edges of water
courses is important in preventing dispersal of seed downstream.
Physical removal
- Physical removal of
gorse will not control an infestation unless it is combined with other
methods of follow-up control. Regular slashing or mowing by themselves
are NOT effective in eradicating gorse because plants will regrow from
cut stumps or dormant seed in the soil as soon as slashing ceases.
Cultivation
- Mechanical clearing is an
ideal method of controlling large infestations on land that is later
sown down with a competitive pasture species. This treatment may require
targeted herbicide spraying of regrowth and a second subsequent sowing
of pasture.
- Avoid causing unnecessary disturbance to the soil, and avoid using heavy machinery along creeks and rivers.
- Follow-up
management is vital. This includes establishment of a vigorous pasture,
grazing of gorse seedlings, and herbicide use on plants surviving
grazing.
Burning
- Frequent burning of gorse
without follow-up will lead to increased germination of seed and more
gorse. Burning should ONLY be used in conjunction with other control
methods.
- Burning is useful for removing large stands of gorse
and making follow-up spraying more effective. Fire destroys large
amounts of seed and stimulates much of the remaining seed to germinate,
so that the seedlings can be sprayed the following year, greatly
reducing the seed in the soil.
- Burning can be useful several months after spraying of an infestation as it reduces the dead stems to ashes.
- Burning
can be useful when combined with grazing by sheep or goats. Burning
will reduce the amount of mature (and unpalatable) foliage and stems of
older bushes, as well as stimulating the growth of seedling-shoots which
are more palatable to grazing animals.
- Gorse burns readily and
gorse fires may cause severe damage to adjacent bush. Extreme care
should be taken when burning gorse near native vegetation, fences or
buildings. Gorse growing underneath high voltage power lines should not
be burned without consulting the power company.
Grazing
- Grazing can be useful when
combined with other control methods such as burning and herbicide, but
is usually not effective on its own at eradicating gorse.
- Grazing
by sheep is only moderately effective at controlling regrowth gorse
seedlings. Sheep will browse gorse bushes during spring or when pasture
feed is in short supply. However, sheep prefer pasture to gorse, and
control of established plants cannot be achieved by sheep grazing alone.
- Goats prefer to browse young gorse shoots rather than pasture.
However well established gorse bushes are not readily killed by goat
browsing alone, and will recover when the goats are removed.
- One
strategy is to burn mature gorse bushes, then stock with goats
supported by large numbers of sheep during spring and early summer to
reduce pasture carry-over. Reducing pasture carryover into late
summer/autumn by sheep-grazing in the spring means that goat browsing
pressure can be maintained on the gorse bushes throughout the growing
season.
Biological control
- Biological control is the use of a living species, usually an insect, mite or disease, to control a weed;
- Biological control will not eradicate gorse, but can be used in conjunction with other control methods;
- Biological
control agents that have been released in Tasmania include the gorse
seed weevil, gorse spider mite, and gorse thrips.
- These gorse
control agents can be released into heavy infestations to reduce the
vigour and abundance of the gorse to assist with other control methods
as part of an integrated management program.
Chemical control
Sensitive environments
There are a number of
sensitive environments where gorse often occurs, and care is needed in
selecting the control method in these environments.
Creeks, rivers and wetlands
- Consider using non-herbicide methods for gorse along waterways
and in wetland areas as chemicals can have significant off-target
effects in these environments.
- If there is no alternative, then ensure that the appropriate herbicide and application techniques are used.
- Avoid using heavy machinery that may cause damage to stream-banks and trigger erosion.
- Gorse control along rivers should be done in conjunction with stock control and revegetation.
- For more advice, contact your Regional Weed Management Officer on 1300 368 550 for advice.
Native bushland
- Avoid clearing with heavy machinery and burning for controlling gorse infestations in native bushland.
- Re-vegetate with local native species.
Integrated management of gorse
In most situations, the most
effective control of gorse will be achieved by a combination of the
above methods rather than using a single method. To maximise the chance
of successfully eradicating an infestation, it is imperative that after
removing or spraying gorse the site is monitored for regrowth over
several years, and any regrowth is dealt with by follow-up control.
Agricultural land
In agricultural situations, herbicide
application, burning, mechanical removal, pasture establishment and goat
and sheep grazing can be combined successfully.
In most
agricultural situations gorse bushes should be removed after spraying to
facilitate the preparation of a seedbed, the sowing of pasture seed and
the herbicide treatment of regrowth. Removing the dead gorse will also
reduce the fire hazard created by the dead bushes. Sprayed bushes should
not be removed until full brownout has occurred. Burning the dead gorse
is also an effective way to reduce the seedbank prior to re-sowing.
Wasteland areas
In wasteland areas such as gullies and rocky
banks where pasture establishment is impractical, spraying or cut-stump
treatment with repeated follow-up treatment are the most effective ways
of preventing reinfestation. In these areas, grazing should be
restricted to prevent soil disturbance and encourage the natural
regeneration of grasses and other plants to compete with gorse
seedlings.
Bushland areas
For bushland areas, mechanical methods (chainsaw,
brushcutter), herbicide application (cut stump treatment) and
revegetation can be combined to control gorse with minimal damage to
surrounding vegetation. Removal by burning will encourage the
germination of gorse and other weeds which will rapidly cover bare areas
left after the fire. Therefore, dead gorse bushes should be removed by
other means with minimal soil disturbance. In the case of wildfire in
bushland, areas known to have had gorse should be inspected for
treatment of germinating gorse seeds following the fire.
To the
extent permitted by law, the Tasmanian Department of Primary Industries,
Parks, Water and Environment (including its employees and consultants)
excludes all liability to any person for any consequences, including but
not limited to all losses, damages, costs, expenses and any other
compensation, arising directly or indirectly from using information or
material (in part or in whole) contained on this website.