Yellow Soldier (Lachenalia Reflexa), Weed Management Guide

This document was originally published on the website of the CRC for Australian Weed Management, which was wound up in 2008. To preserve the technical information it contains, the department is republishing this document. Due to limitations in the CRC’s production process, however, its content may not be accessible for all users. Please contact the department’s Weed Management Unit if you require more assistance. al er t l is t for envi ronment a l weeds

Yellow soldier – Lachenalia reflexa

● Current

Yellow soldier (Lachenalia reflexa) The problem

Yellow soldier is on the Alert List for Environmental Weeds, a list of 28 non

native plants that threaten biodiversity Yellow soldier – Lachenalia reflexa and cause other environmental damage. Although only in the early stages of establishment, these weeds have the potential to seriously degrade Australia’s ecosystems.

Yellow soldier was first recorded as naturalised south of Perth, Western Australia, in 1957, probably after escap ing from a garden planting. It has since become a problem weed and is spread ing through tuart (Eucalyptus gomphocephala) and banksia woodlands Yellow soldier has two strap-shaped leaves which are slightly V-shaped in cross-section. Photo: Kate Brown on sandy calcareous soils. It is most common in the southwest of the state, a region renowned for its high biodiversity Yellow soldier has two strap-shaped Key points leaves, 60–350 mm long and 15–25 mm and unique aesthetic qualities. wide, which grow upwards from the • Prevention and early intervention are the It could become a significant environ- base. The leaves are slightly V-shaped in most cost-effective forms of weed control. Once mental problem because it replaces cross-section. The bright yellow flowers established, yellow soldier is difficult to control native herbs and annuals in both disturb- are 25 mm long and more or less tubular so it is important to keep uninfested areas ed and relatively intact bushland. Apart in shape but swollen in the middle. They weed free. from causing a loss of plant biodiversity, grow on short stalks just 45–100 mm • Yellow soldier produces a large number of viable which destroys habitat and resources for above the ground. seeds that germinate each year, leading to rapid expansion of populations. native animals, infestations of yellow Yellow soldier stores food material for • A number of species of Lachenalia are present soldier can reduce the recreational the next growing season in bulbs, which in Australia but yellow soldier is considered the enjoyment of bushland by people. are short underground stems. Large most widespread and invasive. healthy plants can produce up to ten • Contact your state or territory weed manage- yellow upright flowers. Plants flower The weed ment agency or local council if you find yellow particularly well following fire and set soldier. Do not attempt control on your own. Yellow soldier belongs to a group of prolific amounts of seed. The smooth, South African plants, many of which are shiny black seeds are about 2 mm grown as garden ornamentals. Three long. The seed does not appear to other species of Lachenalia are weeds remain viable in the soil for more than of Western Australia (see Box, p.3). two or three years. 2

Growth calendar Yellow soldier is considered the most widespread and invasive of the natural ised Lachenalia species in Australia. It Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec occurs as a serious weed at a number Flowering of conservation reserves around Perth, Die back Western Australia. It invades banksia/ Germination tuart woodlands and limestone scrub General growth pattern and heath around the Swan estuary, Yellow soldier seeds germinate during spring and flower during the following winter banksia/jarrah woodland to the south and early spring. The above ground foliage dies off during summer. and west of Perth, and tuart woodland up to 40 km north of Perth.

How it spreads Plants have also been observed to Why we need to be ‘alert’ produce a prolific number of bulbils to yellow soldier With only a single annually renewed (small bulbs) around the base of stems bulb, yellow soldier spreads mainly by left lying on the soil surface, but this Yellow soldier could spread over most of seed. There are usually between one and does not appear to be a common the Swan coastal plain in southwestern ten flowers per plant and each flower method of reproduction or dispersal. Western Australia. Based on climatic produces a capsule that contains suitability, it could potentially spread to 40–60 seeds, potentially giving rise to Where it grows areas with sandy soils in South Australia infestations of more than 400 bulbs per and Victoria. square metre. In its native range the genus Lachenalia The infestation in the Shenton extends mainly throughout western and Experience in the Shenton bushland in bushland has shown that yellow soldier southwestern Cape Province in South Western Australia (see case study p. 5), does not need disturbance to establish, Africa, where it occurs in areas with where populations are quite discrete, as many of the infestations occur in winter rainfall, undergoing long dormant suggests that seed is not easily spread relatively intact bushland. This indicates periods over the dry summers. over long distances. Water movement that yellow soldier could become a major environmental weed and potentially have and human activity are the main causes Yellow soldier is most common in the of seed spread. southwest of the state of Western severe impacts in conservation areas, Australia, a region renowned for its displacing more desirable native species Yellow soldier seeds often germinate Yellow soldier – Lachenalia reflexa Yellow high biodiversity and unique and altering the ecological balance of in response to fire, taking advantage aesthetic qualities these areas. of any bare ground and the reduction in competition from native species. There are a number of difficulties associated with controlling bulbous weeds such as yellow soldier growing in native vegetation. See the case study (p. 5) for more information.

What to do about it

Prevention is better than the cure

As with all weed management, prevention is better and more cost- effective than control. The annual cost of weeds to agriculture in Australia, in terms of decreased productivity and management costs, is conservatively Yellow soldier produces a prolific amount of smooth, shiny, black seed. estimated at $4 billion. Environmental Photo: Kate Brown impacts are also significant and lead to

We ed Management Guide • Yellow soldier – Lachenalia reflexa 3

Other weedy naturalised species of Lachenalia

In recent years a number of Lachenalia species have become naturalised in southern Australia. Lachenalia aloides has been recorded as a weed in lowland grassland and grassy woodland in Victoria, while L. aloides and L. bulbifera have been recorded as garden escapees in South Australia. In southwestern Western Australia four species, L. aloides var. aurea, L. bulbifera, L. mutabilis and L. reflexa, have been recorded as weeds. Although these species are still very localised, they are spreading through woodlands in this region. 200 mm The various species of Lachenalia are similar looking, although there is some variation in plant size and flower colour. L. aloides grows 50–310 mm high and has flowers in a range of colours including orange, red, yellow and greenish blue. L. bulbifera grows 80–300 mm high and has orange to red flowers, with darker red or brown markings and green tips. L. mutabilis is the largest of the four species, growing 100–450 mm high, with pale blue and white flowers with yellow tips, and only one leaf. Yellow soldier (L. reflexa) is the smallest species (30–190 mm high) and has pure yellow flowers. L. aloides has flowers in a range of colours including orange, red, yellow and greenish blue. Photo: Penny Hussey a loss of biodiversity. To limit escalation In the past various Lachenalia species of these impacts, it is vital to prevent have been offered for sale in nurseries Early detection and eradication are also further introduction of new weed around Australia, including in Western important to prevent infestations of species, such as yellow soldier, into Australia, South Australia and Victoria. yellow soldier. Small infestations can uninfested natural ecosystems. Notify the vendor or state or territory be easily eradicated if they are detected weed control contacts if you find Yellow soldier flowers particularly early but an ongoing commitment is Lachenalia for sale. well following fire and sets prolific needed to ensure new infestations do amounts of seed not establish.

The Alert List for Environmental Weeds

The Federal Government’s Alert List for Environmental Weeds was declared in 2001. It consists of 28 weed species that currently have limited distributions but potentially could cause significant damage. The following weed species are therefore targeted for eradication:

Scientific name Common name Scientific name Common name Acacia catechu var. sundra cutch tree Koelreuteria elegans ssp. formosana Chinese rain tree Acacia karroo Karroo thorn Lachenalia reflexa yellow soldier Asystasia gangetica ssp. micrantha Chinese violet Lagarosiphon major lagarosiphon Barleria prionitis barleria Nassella charruana lobed needle grass Bassia scoparia kochia Nassella hyalina cane needle grass Calluna vulgaris heather Pelargonium alchemilloides garden geranium Chromolaena odorata Siam weed Pereskia aculeata leaf cactus Cynoglossum creticum blue hound’s tongue Piptochaetium montevidense Uruguayan rice grass Cyperus teneristolon cyperus Praxelis clematidea praxelis Cytisus multiflorus white Spanish broom Retama raetam white weeping broom Dittrichia viscosa false yellowhead Senecio glastifolius holly leaved senecio Equisetum spp. horsetail species Thunbergia laurifolia laurel clock vine Gymnocoronis spilanthoides Senegal tea plant Tipuana tipu rosewood Hieracium aurantiacum orange hawkweed Trianoptiles solitaria subterranean Cape sedge

Weed Management Guide • Yellow soldier – Lachenalia reflexa Quarantine and Inspection Service(AQIS) Call 1800803006 orseetheAustralian they are free ofweeds likeyellowsoldier. with quarantinefirstandcanbe sure that mail order cataloguesunlessyoucheck orfromDo notbuyseedsviatheinternet to beaseriousenvironmental weed. is notencouragedduetoitspotential importation ofyellowsoldiertoAustralia is currently apermittedimport.However, Although ontheAlertList,yellowsoldier further introductions Quarantine toprevent Photo: Greg Keighery Yellow soldieristhesmallestLachenaliaspeciesandhaspure yellowflowers. or territoryEnvironment Protection Authoritiesmaybe required ifherbicidesare tobesprayedonriverbanks. care shouldbetakenwhenusingherbicidesnearwaterwaysbecauserainfallrunningoff thelandintowaterwayscancarryherbicides withit.Permitsfrom state The abovecontactscanoffer adviceonweedcontrol inyourstateorterritory. Ifusing herbicidesalwaysread thelabelandfollow instructionscarefully. Particular Weed control contacts Territory State / NSW ACT WA Qld Vic Tas Tas SA NT Weed Management Guide • Yellow soldier – Dept ofNaturalResources andMines Dept ofPrimaryIndustries/Dept Dept ofInfrastructure, Planning Sustainability andEnvironment Dept ofPrimaryIndustries, Biodiversity Conservation Dept ofWater, Landand Water andEnvironment Dept ofAgriculture Environment ACT and Environment NSW Agriculture Department

90 mm < import conditionsdatabase in gardens and parks.Thedetrimental in Australiahave escapedfrom plantings soldier, whichhaverecently established Some 65%ofweeds,including yellow Raising communityawareness see toAQIS. Report anybreaches ofquarantineyou attached tohikingorcampingequipment. containing seeds,orbringbackseeds do notchoosesouvenirsmadefrom or care whentravellingoverseasthatyou www.aqis.gov.au/icon>. Also,take (08) 93683333 (08) 83039500 (07) 38963111 (08) 89995511 (02) 62079777 1300 368550 1800 680244 136 186 Phone 4 [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] Email Lachenalia reflexa should bemademore aware ofthese potential horticulturalbenefits.Thepublic impacts oftheseweedsfaroutweighany the weedandworsen theproblem. not followedup canactuallyhelpspread Control effort thatispoorly performedor soldier withouttheirexpertassistance. local council.Donottrytocontrol yellow territory weedmanagementagency or be reported immediatelytoyourstateor established, anynewoutbreaks should be eradicatedbefore itbecomes soldier infestations,anditcanpotentially Because there are relatively fewyellow yellow soldier New infestationsof the plant. stalks whichemergefrom the centre of it bearsbrightyellowflowersonshort section. BetweenJuneandSeptember, at thebaseandV-shaped incross- two oppositeleaves,whichare broadest Yellow soldier canbeidentifiedbyits of bushland reduce therecreationalenjoyment resources fornativeanimalsandcan biodiversity, destroyshabitatand Yellow soldiercauseslossofplant do iftheyfindit. to identifyyellowsoldierandwhat impacts, andotherissuessuchashow www.environment.act.gov.au www.dpiwe.tas.gov.au www.agric.nsw.gov.au www.dwlbc.sa.gov.au www.agric.wa.gov.au www.nrm.qld.gov.au www.dse.vic.gov.au www.dpi.vic.gov.au www.nt.gov.au

Website

– Lachenalia reflexa reflexa Lachenalia – soldier Yellow 5

Managing the spread of yellow soldier in a banksia...case woodland near study Perth, Western Australia

At the Shenton bushland, a 21 ha 44%. It also triggered germination of allowed to recolonise treated sites remnant of banksia woodland west of annual weeds. unassisted. Perth, Kate Brown, Project Officer with Wiping the leaves with herbicide was Preventing spread into undisturbed areas the Environmental Weeds Action not effective and was also very labour is the main aim of the control program. Network, has run a three-year trial on intensive. Understanding the current distribution methods of controlling yellow soldier. of the weed allows any new infestations The project was funded through the Spot spraying reduced the cover of yellow to be recognised, recorded and targeted Natural Heritage Trust Bushcare Program. soldier by 65% in one season and for control. appeared to have no significant impact Trials in the banksia/jarrah woodland on native shrubs or herbs. Where no The Friends of Shenton Bushland used commenced in 1998 and measured the the results of the trial to secure funding impact of three different control methods control was carried out, yellow soldier to implement control of yellow soldier on the abundance of yellow soldier: hand increased in cover by more than 30% across the whole infested area. An removal, wiping the weeds with herbicide, between 1998 and 2000. experienced contractor carried out the and spot spraying with a different The herbicide treatments did not signif work. With a total of only about 1 ha herbicide. The amount of cover provided icantly affect native shrubs or perennial invaded, the cost of control is relatively by native vegetation was also measured, herbs. After two years of treatment, low. The local government authority is to test for off-target impacts of the yellow soldier still comprised 12% of expected to continue to fund follow-up control methods. cover the following year, indicating that work until the populations require only Hand removal over two seasons left all any broad-scale application would need occasional hand removal.

native species intact but was very labour to be carefully followed up for a number This case study was adapted from Brown, K. & intensive (up to six hours for 4 m2), of years to prevent the weed reinvading Brooks, K. 2002. ‘Bushland weeds: A practical guide to their management.’ Environmental Weeds

– Lachenalia reflexa reducing cover of yellow soldier by only the area. Indigenous species are being Action Network.

Methods to control Removal by hand soldier’s flowers are clearly visible, and the reduced cover of native vegetation yellow soldier In sandy soils bulbs can be removed by makes the resprouting flowering bulbs hand in late August – early September

Yellow soldier Yellow Any control of yellow soldier should be easy targets for herbicide control. by cutting the roots with a knife and undertaken cooperatively with your state pulling them out with the bulb. or territory weed management agency Legislation However, hand removal is difficult and or local council. time consuming, and can cause major There is no legislation to control yellow soil disturbance which may encourage soldier but, as part of the Alert List for other weeds. It is often impractical on Environmental Weeds, it is marked for a larger scale, especially given the high eradication and should not be imported density at which these bulbous weeds into Australia or further spread. often occur.

Fire is not recommended Acknowledgments for control Information and guide revision: Kate Yellow soldier appears to be tolerant of Brown (Environmental Weeds Action fire and regenerates soon after bushfire. Network), Greg Keighery (CALM WA), Plants appear to flower particularly well Sandy Lloyd (Agriculture WA/Weeds following fire, setting prolific amounts CRC) and John Thorp (National Weeds of seed. In addition, fire reduces comp Management Facilitator). etition from native vegetation and creates bare areas where seed can germinate. Map: Base data used in the compilation Hand removal of yellow soldier is very labour However, fire can create opportunities for of distribution map provided by intensive – up to 6 hours for 4 m2 – and triggers germination of other annual weeds. land managers to prevent further spread Australian herbaria via Australia’s Photo: Kate Brown and establishment. After fire, yellow Virtual Herbarium.

We ed Management Guide • Yellow soldier – Lachenalia reflexa Quick refer ence guide

Identification Reporting occurrences

You will first need to confirm its Once identified, new occurrences of identity. Contact your state or territory yellow soldier should be reported to weed management agency for help in the relevant state or territory weed identifying the plant. You will need to management agency or local council, who will offer advice and assistance on take note of the characteristics of the its control. Because yellow soldier poses plant in order to accurately describe it. such a serious threat, its control should The most striking characteristic of yellow be undertaken with the appropriate soldier is its upright, yellow flower stalk expertise and adequate resources. containing from one to ten flowers and its two strap-shaped leaves emerging Follow-up work will from the base. be required

Once the initial infestation is controlled, follow-up monitoring and control will Yellow soldier appears to be tolerant of fire be required to ensure that reinfestation and regenerates soon after bushfires. does not occur. Photo: Kate Brown Collecting specimens State or territory herbaria can also identify plants from good specimens. These organisations can provide advice on how to collect and preserve specimens. Yellow soldier – Lachenalia reflexa Yellow State/Territory Postal Address Phone Web Australian National GPO Box 1600 (02) 6246 5108 www.anbg.gov.au/cpbr/herbarium/index.html Herbarium Canberra, ACT, 2601 National Herbarium Mrs Macquaries Rd (02) 9231 8111 www.rbgsyd.nsw.gov.au of New South Wales Sydney, NSW, 2000 National Herbarium Private Bag 2000 Birdwood Avenue (03) 9252 2300 www.rbg.vic.gov.au/biodiversity/herbarium.html of Victoria South Yarra, Vic, 3141 Northern Territory Herbarium PO Box 496 Palmerston, NT, 0831 (08) 8999 4516 http://www.nt.gov.au/ipe/pwcnt/ Queensland Herbarium c/- Brisbane Botanic Gardens (07) 3896 9326 www.env.qld.gov.au/environment/science/herbarium Mt Coot-tha Rd Toowong, Qld, 4066 South Australian Plant PO Box 2732 (08) 8222 9311 www.flora.sa.gov.au/index.html Biodiversity Centre Kent Town, SA, 5071 Tasmanian Herbarium Private Bag 4 Hobart, Tas, 7000 (03) 6226 2635 www.tmag.tas.gov.au/Herbarium/Herbarium2.htm Western Australian Locked Bag 104 (08) 9334 0500 http://science.calm.wa.gov.au/herbarium/ Herbarium Bentley DC, WA, 6983

Disclaimer While every care is taken to ensure the accuracy of the information in this publication, the CRC for Australian Weed Management and the Commonwealth Department of the Environment and Heritage take no responsibility for its contents, nor for any loss, damage or consequence for any person or body relying on the information, or any error or omission in this publication.