Narrow-leaf privet is a dense evergreen shrub that produces clusters of strongly perfumed white flowers. It has negative impacts on agriculture, native vegetation and human health.
Narrow-leaf privet invades forests, woodlands, orchards, plantation forests, gardens and areas along waterways. Dense stands of privet out-compete other plants for water, nutrients and sunlight.
Narrow-leaf privet:
Narrow leaf privet has a negative impact on many endangered plants, animals and ecological communities.
Privets can cause the following health problems:
What to do if a person is poisoned:
An unidentified toxin in the leaves and fruit of narrow leaf privet may cause tremors and seizures in poultry. No cases have occurred in Australia.
Small-leaf privet is a densely branched multi-stemmed evergreen shrub about 3–5 m (occasionally growing up to 7 m). In colder areas it may lose leaves through winter.
Narrow-leaf privet looks like two other privets:
Narrow-leaf privet mostly grows in the coastal and tableland areas of New South Wales. Nurseries sold privets as ornamental plants and they were commonly used for garden hedges. Florists also used the flowers.
It is a native plant in China.
Narrow-leaf privet grows best in:
It grows well along creeks, gullies and drainage lines. However, it can also tolerate drier areas if runoff water is temporarily available. It tolerates a range of soil types from sand to heavy clays.
Narrow-leaf privet can tolerate very low light levels and grow under dense forests.
Many privets were planted in gardens especially as hedges.
Mature plants produce up to ten million seeds each growing season. Seeds need to be just below the soil surface or litter layer (to 1 cm) before they grow. The seeds survive only 6–12 months in the soil.
Seeds are spread by:
It can grow new shoots from root and stem suckers. This creates dense stands of privet.
Wide dispersal of seed by birds cannot be controlled; therefore controlling the spread of privet requires the removal of seed trees and young seedlings before they produce seed. Successful weed control requires follow up after the initial efforts. This means looking for and killing regrowth or new seedlings. Using a combination of control methods is usually more successful.
To tackle narrow-leaf privet:
Narrow-leaf privet is sometimes food and habitat for native animals. For these situations, remove it in stages, replacing it with suitable native species.
Narrow-leaf privet was commonly planted as a hedge in the gardens of heritage houses. If these hedges are to be kept, regular trimming should be done to stop flowering and seed set.
These methods will reduce the seeding capacity of a large infestations but will not eradicate it. Follow-up with herbicide control or manual removal. Revegetate treated areas with trees, shrubs, ground covers or pastures and repeatedly hand-weeded or slashed. Do not use mechanical removal in steep areas or near water courses.
Pull or dig out small to medium sized plants by hand. If the root segments break, dig them out to prevent regrowth. Hang plants upside down to dry out the roots. This method minimises impacts on native plants and soil disturbance.
Earth-moving machinery may be used for removal of dense stands of privet if high levels of soil disturbance can be tolerated.
Large areas of seedlings or regrowth can be slashed.
Burning is not an effective control measure because privet is not very flammable and bush fires do not usually move through privet dominated vegetation. Narrow-leaf privet can regenerate after fires have killed all above-ground plant parts. Fire can be used as an initial control measure if followed the next year by treating regrowth with cut stump herbicide applications. Frequent burning may help control seedlings in infested eucalypt forests and woodlands.
There are no introduced biological control agents available for privet control in Australia.
Increased nutrient levels often contribute to the presence of privet infestations. Reducing or stopping the movement of nutrients in water from residential or industrial areas into riparian areas may help prevent establishment of large privet infestations.
Spraying is suitable for plants up to 3 m tall and those in dense infestations when there is no risk of spraying desirable vegetation. Spray actively growing plants that are not under any heat or moisture stress. Completely cover all the foliage for successful control.
Gas or splatter guns apply low volumes of high concentration herbicide to plants 6–10 m away. Add marker dye to help identify treated areas. This method minimises off target damage because only a small number of leaves need to be treated and large sized droplets are used.
Check the label for the maximum treatable diameter as it varies between herbicides (5- 10 cm). Paint or spray the herbicide mix all the way around every trunk and lower stem from the ground up to a height of 30 cm. Wet thoroughly to the point of runoff. Do not apply to wet stems as this can repel the diesel mixture.
This method is effective on plants of various sizes. Cut trunks or stems within 15 cm of the ground if possible. Spray or paint on herbicide to the stumps within 15 seconds of cutting. Treat every stump.
This method is suitable for large plants. It is cost effective in terms of labour and volume of herbicide required. Drill or make cuts into the sapwood and fill with herbicide within 15 seconds of making the cut. Treat every stem.
See Using herbicides for more information.
Glyphosate 360 g/L
(Various products)
Rate: Undiluted (1–2 mL per cut)
Comments: Stem injection. Apply 1 mL/cut for trees with trunk diameter 25 cm or less at the base. Apply 2 mL/cut for trees with trunk diameter over 25 cm and up to 60 cm at the base,
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate
Metsulfuron-methyl 300 g/kg + Aminopyralid 375 g/kg
(Stinger™)
Rate: 20 g per 100 L of water (always add a Wetter 100 mL/100L)
Comments: Hand gun application. Apply to bushes up to 3 m high. Complete foliar spray coverage is essential for control. Adjuvant: Wetter 1000g/L non-ionic alcohol alkoxylate (TITAN WETTER 1000 or BS1000 or equivalent).
Withholding period: Pastures - Grazing for meat production or cutting for animal feed: Do not graze for 56 days after application. See label for further details
Herbicide group: 2 (previously group B), Inhibition of acetolactate and/or acetohydroxyacid synthase (ALS, AHAS inhibitors) + 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: High/Moderate
Metsulfuron-methyl 600 g/kg
(Various products)
Rate: 10 g per 100 L of water
Comments: Apply to bushes up to 3 m high; complete coverage is essential.
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: 2 (previously group B), Inhibition of acetolactate and/or acetohydroxyacid synthase (ALS, AHAS inhibitors)
Resistance risk: High
Metsulfuron-methyl 600 g/kg
(Various products)
Rate: 1 g per litre of water + organosilicone penetrant (10 mL/5L)
Comments: Gas gun / Splatter gun application. Apply only to bushes up to 3 m high when in full leaf and actively growing. Thorough coverage is essential.
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: 2 (previously group B), Inhibition of acetolactate and/or acetohydroxyacid synthase (ALS, AHAS inhibitors)
Resistance risk: High
Picloram 44.7 g/L + Aminopyralid 4.47 g/L
(Vigilant II ®)
Rate: Undiluted
Comments: Cut stump application: Apply a 3–5 mm layer of gel for stems less than 20 mm. Apply 5 mm layer on stems above 20 mm. Stem inject application for trees: Make a series of cuts 15-20 mm deep around the trunk using an axe or saw. Space cuts evenly with no more than a 20-40 mm gap between them. Apply a 5 mm layer of gel over the lower surface of the cut.
Withholding period: Nil.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
Triclopyr 240 g/L + Picloram 120 g/L
(Access™ )
Rate: 1.0 L per 30 L of diesel
Comments: Basal bark/cut stump application.
Withholding period: Nil
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
Triclopyr 600 g/L
(Various products)
Rate: 1.0 L per 12 L of diesel
Comments: Basal bark application for plants with stems up to 10 cm diameter at the base. Cut stump application for plants with stems up to and greater than 10 cm diameter at the base. Treatment may be carried out at any time of the year.
Withholding period: Not required when used as directed.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
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 pest 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. |
Central Tablelands
Contain recorded populations across the Central Tablelands region. Excludes urban areas across the region except for Orange City Council. Orange City Council has a local privet management plan to control privet in the urban areas. |
Regional Recommended Measure* (for Regional Priority - Containment)
Whole of region: Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. Duty does not apply for urban areas in the Central Tablelands region other than Orange City Council. |
*To see the Regional Strategic Weeds Management Plans containing demonstrated outcomes that fulfil the general biosecurity duty for this weed click here |
Reviewed 2023