Sweet briar (Rosa rubiginosa)

Sweet briar is a thorny, perennial shrub. Widespread in NSW, it is more common in cooler, high rainfall areas.

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How does this weed affect you?

Sweet briar is a native of Europe that now grows throughout the world. Sweet briar can reduce the carrying capacity of land, harbour rabbits, restrict vehicle access and restrict stock movements, especially where it occurs in clumps or patches.

Where is it found?

The plant is widespread in NSW but is more common in the cooler, high rainfall areas. The worst infestations are usually found on the tablelands and cooler slopes.

How does it spread?

Sweet briar is spread mainly by birds or animals eating the fruit and distributing the viable seed. Fruits and seeds can also be spread by run-off in steep country along creeks and streams. The seeds can remain viable in the soil for up to 4 years. Root pieces and disturbed crowns of sweet briar can also produce new growth or suckers.

What does it look like?

Sweet briar is an erect perennial shrub, commonly growing 1.5 to 2 m high but can be up to 3 m.

Many stems arise from a shallow, perennial rootstock. They are smooth when young and become rough and woody as the plant ages. They arch towards the top and have numerous backward curving flat thorns up to 1.5 cm long.

The leaves are pinnate and have an apple-like fragrance. They consist of 2 to 4 pairs of oval leaflets plus one terminal leaflet. The leaflets have serrated margins and short prickles on the leaf stems.

Flowers usually appear in late spring and are pink or white with 5 petals and long green sepals or leaflike structures at the flower base. They form in loose clusters at the ends of the branches and are also fragrant.

The fruits are orange-red in colour, oval shaped with short spines and contain numerous, yellow, irregularly shaped seeds. The sepals remain attached to the fruit.

The extensive roots are at least 1 m long and are usually confined to the top 30 cm of soil.

Habitat

Sweet briar often invades unimproved grasslands and disturbed bushland. It prefers well-drained areas of moderate fertility with little competition and light grazing. The weed can grow on most soil types.

Generally, it is confined to areas in NSW with an annual rainfall greater than 600 mm. However, in lower rainfall areas, infestations can still occur in moist gullies and protected sites.

Infestations are often heaviest in hilly and rocky country around trees on creek banks and along fence lines.

References

Clements B, Dellow JJ and McCaffery AC (2005). Sweet briar, Primefact 88. NSW DPI, Orange. 

The authors would like to acknowledge the comments made by Tony Cook and Clare Edwards regarding the technical content of this publication.

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Control

The effective, long-term control of this weed may require the integration of a number of techniques including mechanical removal, pasture management, grazing management, herbicide application, regular monitoring and replacement with appropriate plants.

For invasive, woody weeds such as sweet briar, control is more effective and economical if done when the plants are young.

The control methods used will depend on the infestation size and location. For advice on the most appropriate methods for your situation, consult your local agronomist or council weeds officer.

Mechanical removal

Established plants can be removed by hand grubbing, bulldozing or tractor and chain. This is easier and more effective when the ground is wet. Deep cultivation can be effective on arable land as it exposes and kills the bulk of the root system.

However, it can be difficult if the bushes are large or dense. After the initial removal, further cultivations in summer will ensure the remaining root system is exposed and killed. Normal autumn cultivations before sowing pastures or crops will kill any remaining seedlings.

The site should be monitored regularly and any regrowth should be treated with repeat cultivations or by spraying with an appropriate herbicide once it is a sufficient size (refer to the chemical label).

Pasture management

Vigorous perennial pastures provide competition to reduce the invasion of sweet briar. In suitable sites, they should be established as soon as possible after the removal of the weed infestation but not after the application of residual herbicides.

Consult your local agronomist for advice on pasture establishment and appropriate pasture management. For further information refer to a range of NSW Department of Primary Industries (DPI) publications available at any DPI office or www.dpi.nsw.gov.au/agriculture.

Grazing management

Grazing management is also useful in controlling sweet briar. Sheep will readily graze young seedlings and help prevent their establishment.

Cattle are not as good at preventing seedling establishment and an increase in sweet briar infestations is often noticed after graziers switch from sheep to cattle.

Sweet briar is highly palatable to goats so they can be very successful in controlling infestations. They will readily graze both established plants and seedlings, continually defoliating all accessible stems and eventually ringbarking them. This kills established plants and prevents seedlings from establishing.

Chemicals

Only use registered herbicides according to the label directions.

Herbicides can be applied to sweet briar in many different ways. The most appropriate form of herbicide application will depend on the location, size and maturity of the infestation.

Treated infestations should be regularly monitored for regrowth because seedlings, spray errors and root shoots (suckers) can occur over a period of years. Regrowth should not be treated with an appropriate herbicide until it is of sufficient size (refer to the chemical label).

Foliar Spray

Applying chemicals through foliar spraying is more effective when the plant is actively growing.

Foliar spraying is the most commonly used method of control. For effective control spray the whole bush thoroughly when soil moisture is adequate and the plant is actively growing. This will vary depending on location but is generally during late spring to early autumn. The plant should be in full leaf, prior to leaf fall (refer to the chemical label for the most appropriate time). Insufficient herbicide coverage is a common mistake and is probably the largest cause of survival.

A systematic approach is required when spraying. Spraying should commence at the top of the bush and work down to the base. Seedlings and suckers around the drip zone of the plant also need to be treated.

For effective results, DO NOT treat infestations during hot, dry, summer periods or when the plant is stressed from drought, waterlogging, cold or without leaf.

Basal Bark Treatment

Basal bark application of chemicals should be to the complete base of every stem to a height of 30–40 cm above the ground.

This technique is less effective but is appropriate for infestations in environmentally sensitive locations. It is most suited for small bushes with stems less than 5 cm in diameter.

Spray an appropriate herbicide mixed with diesel around the COMPLETE BASE OF EVERY STEM to a height of 30–40 cm above the soil surface. Check the chemical label for the correct mixing ratio.

Ensure that stems and bark are not wet at the time of application as water will repel the diesel mixture. Basal bark treatments also work best if plants are actively growing.

Cut Stump Treatment

In cut stump applications it is important to apply the chemical immediately to the cut stem.

This technique is labour intensive but is also appropriate for small infestations in environmentally sensitive locations. It is most suitable for large plants with a stem diameter greater than 5 cm.

Cut each stem off 15 cm above the soil surface. Liberally apply an appropriate herbicide mixed with diesel (check the chemical labels for the correct mixing ratio) to the cut surface within 30 seconds of the cut being made.

If the herbicide is not applied immediately, the plant will heal the cut, the chemical will not be translocated through the plant and control will not be effective.

Root Application

Great care must be taken when using this technique.

Many desirable trees, in particular eucalypts, are susceptible to the residual herbicides used for this control method. DO NOT use these chemicals within a distance of at least twice the height of adjacent desirable trees or shrubs.

To control sweet briar, apply an appropriate residual herbicide directly under the plant near the base. The herbicide should be applied under the soil to prevent degradation by sunlight and possible contamination of surface run-off after rain. It is most effectively applied when the soil is moist.

Deep-rooted plants may need to be retreated after 2 years if they are still partially green.

Herbicide options

WARNING - ALWAYS READ THE LABEL
Users of agricultural or veterinary chemical products must always read the label and any permit, before using the product, and strictly comply with the directions on the label and the conditions of any permit. Users are not absolved from compliance with the directions on the label or the conditions of the permit by reason of any statement made or not made in this information. To view permits or product labels go to the Australian Pesticides and Veterinary Medicines Authority website www.apvma.gov.au

See Using herbicides for more information.


2,4-D 300 g/L + Picloram 75 g/L (Tordon® 75-D)
Rate: 650 mL in 100 L of water
Comments: Full leaf as an overall spray.
Withholding period: 1-8 weeks (see label).
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


Glyphosate 360 g/L (Roundup®)
Rate: 1.5–2.0 L in 100 L of water
Comments: Spray to wet all foliage, from late flowering to leaf fall. Use higher rate on bushes over 1.5 m high.
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate


Glyphosate 360 g/L (Roundup®)
Rate: 1 part per 9 parts water
Comments: Gas gun / Splatter gun application. Apply 2 by 5 mL doses per 0.5 m of bush height.
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate


Glyphosate 835 g/kg + Metsulfuron-methyl 10 g/kg (Trounce®)
Rate: 1 measured pack (173 g) in 100 L of water
Comments: Apply as close to the flowering period as possible.
Withholding period: Nil (recommended not to graze for 7 days before treatment and for 7 days after treatment to allow adequate chemical uptake in target weeds).
Herbicide group: B, Inhibitors of acetolactate synthase (ALS inhibitors) + M, Inhibitors of EPSP synthase
Resistance risk: High/Moderate


Hexazinone 250 g/L (Velpar® L)
Rate: Undiluted (4 mL per spot)
Comments: One spot per metre of height. Do not apply near desirable trees.
Withholding period: No stated withholding period.
Herbicide group: C, Inhibitors of photosynthesis at photosystem II (PS II inhibitors)
Resistance risk: Moderate


Metsulfuron-methyl 300 g/kg + Aminopyralid 375 g/kg (Stinger™)
Rate: 20g in 100 L of water
Comments: Hand gun application
Withholding period: 3 - 56 days (see label)
Herbicide group: B, Inhibitors of acetolactate synthase (ALS inhibitors) + I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: High/Moderate


Metsulfuron-methyl 600 g/kg (Brush-off®)
Rate: 10 g in 100 L of water
Comments: Apply to actively growing bushes to point of run. Do not apply after end of February.
Withholding period: Nil (recommended not to graze for 7 days before treatment and for 7 days after treatment to allow adequate chemical uptake in target weeds).
Herbicide group: B, Inhibitors of acetolactate synthase (ALS inhibitors)
Resistance risk: High


Metsulfuron-methyl 600 g/kg (Brush-off®)
Rate: 1 g/L + organosilicone penetrant
Comments: Gas gun / Splatter gun application. Apply during the flowering period. Ensure thorough coverage of all leaves and stems.
Withholding period: Nil (recommended not to graze for 7 days before treatment and for 7 days after treatment to allow adequate chemical uptake in target weeds).
Herbicide group: B, Inhibitors of acetolactate synthase (ALS inhibitors)
Resistance risk: High


Picloram 100 g/L + Triclopyr 300 g/L + Aminopyralid 8 g/L (Grazon Extra®)
Rate: 350 or 500 mL in 100 L of water
Comments: Foliar application for plants up 1.5m tall
Withholding period: Where product is used to control woody weeds in pastures there is a restriction of 12 weeks for use of treated pastures for making hay and silage; using hay or other plant material for compost, mulch or mushroom substrate; or using animal waste from animals grazing on treated pastures for compost, mulching, or spreading on pasture/crops.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


Picloram 44.7 g/kg + Aminopyralid 4.47 g/L (Vigilant II ®)
Rate: Undiluted
Comments: Cut stump/stem injection application. Apply a 3–5 mm layer of gel for stems less than 20 mm. Apply 5 mm layer on stems above 20 mm .
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


Triclopyr 240 g/L + Picloram 120 g/L (Access™ )
Rate: 1.0 L in 60 L of diesel
Comments: Basal bark/cut stump application.
Withholding period: Nil
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


Triclopyr 240 g/L + Picloram 120 g/L (Access™ )
Rate: 500 mL per 10 L of water
Comments: Gas gun / Splatter gun application. Apply to actively growing bushes.
Withholding period: Nil
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


Triclopyr 300 g/L + Picloram 100 g/L (Grazon® DS)
Rate: 350 or 500 mL in 100 L of water
Comments: Full-leaf to ripe fruit prior to leaf fall. Use higher rate on bushes over 1.5 m high.
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


Triclopyr 600 g/L (Garlon® 600)
Rate: 1.0 L in 30 L of diesel
Comments: Basal bark/cut stump application
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


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Biosecurity duty

The content provided here is for information purposes only and is taken from the Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.

Area Duty
All of NSW General Biosecurity Duty
All plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable.
North West Regional Recommended Measure*
Land managers should mitigate the risk of new weeds being introduced to their land. Land managers should mitigate spread from their land. The plant should not be bought, sold, grown, carried or released into the environment.
Northern Tablelands Regional Recommended Measure*
Land managers should mitigate the risk of new weeds being introduced to their land. Land managers should mitigate spread from their land. The plant should not be bought, sold, grown, carried or released into the environment.
*To see the Regional Strategic Weeds Management Plans containing demonstrated outcomes that fulfill the general biosecurity duty for this weed click here

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Reviewed 2017