Quick Facts

Quick facts

• Originally from South American, Lippia (Phyla canescens) is an environmental and agricultural weed in temperate and sub-tropical Australia.
• It form dense stands and is unpalatable to stock and has serious implications for the grazing industry through potential decreases in pasture productivity.
• Can cause soil erosion and collapse of banks in to water ways due to long 2 metres tap root
• It spreads both vegetatively and by seed, enabling it to spread across vast areas of land.
• It is difficult to control, with long-term control of Lippia is best achieved through an integrated approach over many years.
• Control may be achieved using herbicides, mechanical control, pasture improvement and grazing management.

What Does It Look Like?

What is it?

Lippia (Phyla canescens) is a fast summer-growing, dense mat-forming, prostrate (growing along the ground), broadleaved perennial herb. When in competition with other species, it can grow to a height of 20–30 cm, and dominate other plants. Once dominance is established, Lippia tends to become more prostrate and lower growing. Stems are green to purple in colour when young and can become somewhat grey and woody with age. Roots are produced from leaf axils along stems, helping it form dense carpets. The plant develops a thick woody taproot a deep taproot up to 2 metres deep. Leaves are 10-30 mm long and nd 3–7 mm wide, arise in pairs at stem nodes and are oval to slightly obovate (egg-shaped with the widest part near the tip), and narrow towards the leaf base (Munir 1993). Leaf margins are toothed to bluntly toothed towards the tip, but sometimes but rarely entire (without teeth). Leaves and stems  are greyish-green due to a covering of fine hairs on their surface.

Flowers are produced in tight clusters, small white to purple cream, pinkish or pale lilac, produced in heads about 10 mm in diameter, on long stems 15–45 mm, arising from leaf axils (just below were the leaf joins the stem).

Fruits are 1–1.5 mm in diameter and release two tiny brown, oval, flattened seeds at maturity (Lucy et al. 1995). The seeds are tiny and barely visible to the naked eye (Leigh & Walton 2004).

Recognition: This species can normally be recognised by the combination of the following characters; dense mat-forming, prostrate (growing along the ground), broadleaved perennial herb, sometimes form mono-cultures; has a woody taproot a deep taproot up to 2 metres deep; leaves are 10–30 mm long, arise in pairs from stem, oval to slightly egg-shaped with small teeth on margin; flowers are produced in tight clusters 10 mm in diameter, on long stems 15–45 mm.

For further information and assistance with identification of Lippia contact the herbarium in your state or territory.

Flower colour

Multi coloured: White to cream, purple to pinkish or pale lilac

Growth form (weed type/habit)

Herb

Where it currently grows? Preferred habitat

Lippia does best in temperate and sub-tropical areas and occurs over a wide variety of soil types in open, seasonally wetted areas and along edges of water bodies (Julien & Duggin 2007). Lippia is well adapted to the floodplain environments of river systems in temperate to subtropical areas. The plant tolerates frost and drought and established plants can survive inundation by floodwater for at least three months. Lippia will grow in heavy clay soils, as well as lighter clays and sandy soils (DPI NSW, 2019). Lippia can tolerate drought and frost, and can survive long periods of inundation. It readily establishes on bare ground and has the ability to take over large areas of land along waterways and adjacent higher ground (DAF, Queensland Government 2020).

Are there similar species?

Lippia is closely related to the species in the genera Lippia and Lantana. Most Lippia and Lantana are either shrubs or sub-shrubs, in contrast to the trailing prostrate form of Phyla (Munir 1993).

In Australia Lippia (Phyla canescens) will be confused with Phyla nodiflora. The leaves of P. canescens are covered with fine greyish hairs and have blunt short teeth on the margins, while those of P. nodilfora lack the grey hairs and have sharp more pronounced teeth on the margins (Munir 1993). The major occurrences of P. nodiflora are in the higher rainfall, more humid coastal regions, and the species appears to be adapted to lighter, sandy soils whereas Lippia is found in the lower, more temperate regions of Australia and appears well adapted to heavier clay soils, particularly in floodplain environments (Lucy et al. 1995).

Why Is It A Weed?

What are its impacts?

Lippia was included in the list of 71 species that were nominated by state and territory governments for assessment as Weeds of National Significance (WoNS). Following an assessment process, Lippia was not included as one of the 20 WoNS. However, it remains a weed of potential national significance. It is a serious environmental and pastoral weed in the Murray-Darling river system in Queensland and New South Wales. Lippia is well adapted to floodplains and adjacent areas, and is extremely difficult to control. In Queensland the area covered by Lippia was recorded as 1 million hectares from a total catchment of 2.5 million in the Condamine catchment, and 1.16 million hectares of the Border Rivers catchment (both New South Wales and Queensland) (Earl 2003). It has little to no grazing value and causes major environmental impacts in terms of increasing soil erosion and decreasing stream bank stability due to loss of perennial grasses and the reduction of plant diversity (DPI NSW 2019).

Agriculture: Lippia probably imposes its most long-reaching impact on primary production in grazing country. It appears to be either unpalatable to stock and/or too short to be easily consumed. Infestations can dominate pastures and lead to reduced stocking rates or productivity of grazing lands. Sheep grazing on Lippia can develop copper deficiency which is detrimental to the quality of their wool. (Leigh & Walton 2004). An aggressive weed that out-competes pasture species, reducing stocking rates by up to 90% (DAF, Queensland Government 2020).

It is also thought that Lippia can reduce seed set in commercial crops as bees prefer Lippia to Lucerne flowers. As a result, pollination of the commercial crop is reduced. It may reduce water availability to crops and inhibit the germination and growth of other plant species, for example, lettuce crops. However, this inhibitory affect may be due to the dense mass of roots left by a Lippia infestation physically preventing other plants establishing rather than an allopathic affect (inhibition of establishment and growth of other individual plants or species by releasing chemical compounds into the environment) (Leigh & Walton 2004).

Native ecosystems:  Lippia is an environmental and economic weed in some parts of Queensland and is already a significant problem in New South Wales (Leigh & Walton 2004). Serious environmental and pastoral weed in Murray-Darling river system. Poses a serious threat to protected wetland areas forming dense carpet-like spread prevents growth of other riparian vegetation. The spreading nature and deep rooting system of Lippia are some of the main concerns with this plant. Both characteristics are associated with stream bank and soil erosion, structural damage to roads, and high control costs (Leigh & Walton 2004). The plant has a taproot up to 2 metres deep and in river or creek bank situations these large taproots act like wedges and will actually cause large sections of the bank to break away and fall into the waterway (NWWCC 2002), resulting soil erosion, decreasing bank stability and degrading waterway health and quality.

Urban areas: In urban areas it can invade lawns and take over especially in lawns prone to flooding.

How does it spread?

Lippia spreads both vegetatively and by seed, enabling it to spread to vast areas of land.

Seed can remain viable for many years (probably well over 10) and seed banks under infestations can contain up to 10 000 seeds per square metre. Seeds must be covered with water for a short period in order to germinate. Any area where water may sit for a week or more (including cattle hoof prints or wheel ruts) provides opportunity for Lippia seed to germinate. Lippia seeds also require light and fluctuating temperatures (daily temperature fluctuations of 10 degrees or more) in order to germinate DPI NSW 2019).

Vegetative material breaks off the main plant during flooding events  quickly re-establish in moist soils as floodwater subsides (DPI NSW 2019) or material can remain dormant until suitable environmental conditions occur (Leigh & Walton 2004). Fragments and seed can also be spread by vehicles, machinery and animals but most spread occurs in response to flood events.

What is its history in Australia?

Lippia is known to have been in Australia from the 1920s, introduced as a lawn ornamental (Leigh & Walton 2004).

Lippia (Phyla canescens) was taxonomically separated from Phyla nodiflora in 1993 (Munir 1993). Many of the reports prior to 1993 of Lippia in Australia are very likely to be about Phyla canescens, rather than P. nodiflora (Leigh & Walton 2004).

How To Manage It?

Best practice management

Long-term control of Lippia is best achieved through an integrated approach involving use of herbicides, mechanical control, pasture improvement and grazing management (Motley et al. 2001). However, it may be difficult to implement control strategies in some cases, as there are many situations where conventional control methods are either uneconomic or impractical (Lucy et al. 1995). Although the species has been subject to years of trials by landholders and researchers, a comprehensive manual of treatment methods for all situations has not been developed. For further information about control methods for Lippia see; DPI NSW (2019); Department of Agriculture and Fisheries, Queensland Government, (2020).

Chemical control: A broad-leaved weed that occurs in pasture situations, some herbicides can be used to reduce Lippia infestations without harming competitive grasses. No herbicide will effectively suppress growth in the long term. Due to Lippia's ability to rapidly recover and spread. Multiple herbicide applications within a season have been shown to give better suppression than single applications. However, herbicide control can become costly in areas with large infestations. Herbicide control is not suitable in riparian areas due to risk of polluting waterways. Also, herbicides should not be applied immediately after rain or if heavy rain is forecast. Please see the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au .

Non-chemical control: Physical control, in paddocks short-term control can be achieved where infestations can be ploughed or harrowed. This method is not practical if Lippia is growing in riparian zones (such as creekbanks) due to high risk of erosion and soil loss. Not usually a problem in cropping areas as can be readily ploughed into soil. However, machinery easily spreads Lippia, so machinery working in infested areas should be washed down before leaving area. When Lippia is actively growing and soil moisture levels are good, herbicide can be used in conjunction with mechanical control to give better results.

Grazing management, DPI NSW (2019) state as a general rule, do not graze new pasture grasses until they have become well established and are producing tillers. Sensible grazing in the establishment year can promote tillering and increased seed production.

Biological control: There are no biological control agents currently available for Lippia, and to date it has not been targeted for research. (Leigh & Walton 2004)

Does it have a biological control agent?

NO

When does it grow? (lifecycle/growth calendar)

Lippia flowers anytime in the spring-summer-autumn period given favourable soil moisture conditions (Lucy et al. 1995; Dellow et al. 2001). Flowering can be triggered by rain or flooding at any time during this period (Lucy et al. 1995). Lippia can self- and cross-pollinate (McCosker 1994) resulting in a high percentage seed set and maintenance of sufficient genetic variation to adapt and rapidly colonise new environments (Kumar & Dutt 1989). Studies on the size of the seed bank and longevity of Lippia seeds in the soil are required.

Germination can occur under a wide range of conditions, and a viable seed bank remains around a parent plant even after the plant's removal (McCosker 1994; Lucy et al. 1995). Research suggest that seeds of Lippia may possess an effective drought survival mechanism involving enhanced germination from the seed bank as a result of alternate drying and wetting (McCosker 1994; Leigh. & Walton 2004).

Where Is It Found?

Which states and territories is it found?

NSW, QLD, SA, VIC, WA

What areas within states and territories is it found?

Lippia is not found in the Northern Territory, Tasmania, or in the more northern parts of Queensland and Western Australia (Lucy et al. 1995; Lazarides et al. 1997).

In South Australia and Victoria, Lippia is widely distributed across the more temperate, floodplain regions of the Murray-Darling Basin. The dense distribution of Lippia in this river system appears to extend from the Murray-Goulburn, along the Murray valley and into the lower reaches of the catchment (Leigh & Walton 2004).

In New South Wales, Lippia has established along the Lachlan River and floodplain system west of Forbes, the Murrumbidgee River floodplains in the Hay area, in the Macquarie Marshes, and throughout the lower Gwydir, McIntyre and Namoi valleys in the north (Dellow et al. 2001).

In Queensland Lippia occurs throughout the Condamine River catchment, from its source near Killarney, to the Balonne River junction (McCosker 1994). Lippia has been found in Myall Creek, Oakey Creek, Ashall and Fourteen Mile creeks, Condamine River, Hodgson Creek, Kings Creek, Dalrymple Creek and Southwest Creek sub-catchments (Phillips & Moller 1995). A recent survey (Earl 2003) found Lippia present in the four catchments of the Murray- Darling Basin in Queensland; Border Rivers, Condamine, Maranoa-Balonne and Warrego-Paroo. Lippia was found in a number of townsites and along both the Maranoa and Balonne rivers. Only individual plants were found along the Warrego River. Lippia also has been observed in more northerly regions of Queensland (Leigh & Walton 2004).

In Western Australia it has been recorded around Northam, Tammin and then further east into the Kalgoorlie region (Florabase 2007).

Where does it originate?

According to most literature, Lippia is native to the South American (Richardson 1994; USDA 2003), and naturalised elsewhere. However, as a widely cultivated species, the origins of this species are not clear. For example, Lippia has recently been recorded as having only a tropical to subtropical world distribution (Dellow et al. 2001) but this is not confirmed by its current distribution across a large range of climatic types (Leigh & Walton 2004).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?

NO

Where is it a declared weed?

Not declared in any Australian states or territories.

Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?

NO

Government weed strategies and lists – Weeds Australia

Is it on the Agricultural Sleeper List?

NO

Government weed strategies and lists – Weeds Australia

Names And Taxonomy

Main scientific name

Phyla canescens

Other scientific names (synonyms)?

• Lippia canescens Kunth
• Lippia nodiflora f. canescens (Kunth) Kuntze
• Lippia nodiflora var. rosea (D.Don) Munz
• Phyla nodiflora var. canescens (Kunth) Moldenke
• Phyla nodiflora var. rosea (D.Don) Moldenke
• Zapania canescens (Kunth) Gibert (incorrect spelling)
• Zapania nodiflora var. rosea D.Don (incorrect spelling)
• Zappania canescens (Kunth) Gibert
• Zappania nodiflora var. rosea D.Don
• Lippia nodiflora (L.) Michx. (misapplied by Ewart, A.J. 1931, Verbenaceae. Flora of Victoria. 974.)
• Lippia nodiflora var. repens (Bertol.) Schauer (misapplied by Ewart, A.J. 1931, Lliliaceae. Flora of Victoria. 974.)
• Lippia nodiflora var. sarmentosa (Willd.) Schauer (misapplied by Ewart, A.J. 1931, Verbenaceae. Flora of Victoria. 974.)
• Phyla nodiflora (L.) Greene (misapplied by Willis, J.H. 1973, A Handbook to Plants in Victoria Edn 2. 2: 579.; Munir, A.A. 1986, Flora of South Australia Edn 4. 3: 1175, Fig. 544B.)

Does it have other known common name(s)?

Carpetweed, Fogfruit, No-man Grass, Phyla, Red Flower, Condamine Couch.