Recorded distribution Periwinkle (Vinca major

1 The problemPeriwinkle, also known as blueperiwinkle (Vinca major ) is a creepingplant that is native to Europe andnorthern Africa and has been introducedto other continents as an ornamentalplant or medicinal herb. In the higherrainfall regions of southern Australia it has escaped from cultivation and isinvading native vegetation where itsbroad-leaved runners form a densemat over other plants. It competeswith native plants for moisture, light,nutrients and recruitment niches. Itsgrowth is particularly vigorous in riparianand other moist habitats. Invasion ofriparian habitats by weeds is among a range of factors contributing to their decline. That is why this is a verysignificant issue for biodiversity,landscapes and river health.

2 In EastGippsland Victoria, Periwinkle hasinvaded temperate rainforest and hasbeen identified as a threat toendangered and vulnerable plantspecies. A dense canopy of periwinklecan also alter fauna such as Periwinkle that reproducevegetatively can establish rapidly fromstem fragments at disturbed sites suchas flood zones and areas recentlycleared of dense weed infestations. Ina recent experimental study of nativetree seedlings in riparian zones invadedby Periwinkle in Victoria, survival ofnative manna gum (Eucalyptus viminalis)seedlings was greater in plots initiallycleared of Periwinkle to a diameter of120 cm. Blackwood (Acacia melanoxylon)seedlings were taller in similar sizedplots cleared of Periwinkle than inuncleared plots.

3 Invasion and establishment of exoticvines and scramblers is a key threateningprocess under the NSW ThreatenedSpecies Conservation Act 1995of whichperiwinkle is one of the species is spreading in southernAustralia at the site level throughexpansion of existing patches, andmore widely through pieces of planttaking root at new locations. Continuedplanting of Periwinkle in gardens couldcontribute to its further spread. Onceestablished, Periwinkle s rampant growthis very difficult to control, especially inbushland. Restrictions on its sale andtransport are under consideration in theVictorian noxious weeds review. Managing weeds for biodiversityPeriwinkle Vinca majorBlue Periwinkle (Vinca major ) can form a carpet in native vegetation, NSW.

4 Photo: Jackie Miles and Max CampbellPeriwinkle (Vinca major )Key points Periwinkle s broad-leaved runners form a dense mat, shading out native plants and competing for moisture and nutrients. It mainly spreads vegetatively but somepatches also produce seeds. Very small isolated patches (<1 m2) can be dug out. Stem and root fragments canresprout so all plant material needs to beremoved from the site and disposed ofappropriately. Herbicide treatment can be effective if applied when plants are actively growing and followed up. Along waterways, particular care is neededwith physical or chemical treatments toprevent erosion and contamination. Theremay be restrictions on chemical use.

5 All treatment needs to be followed up forseveral years. Integrated control of Periwinkle and otherweeds, and perseverance are essential forrestoring native vegetation. Recorded distributionThe weedPeriwinkle has a woody crown bearingrunners up to 1 m long with large,stalked, opposite leaves (15 60 mmlong, 14 45 mm wide). Each leaf pairis generally at right angles to thoseabove and below. The upper leaf surfaceis glossy and there are generally veryshort hairs along the leaf are large, 30 40 mm across andblue-purple or sometimes white, with5 lobes from a basal tube 16 17 mmlong. They are borne on upright stemsto 50 cm long. The root system is hardyand fibrous, forming a mat 15 30 cmdeep in the soil.

6 Most populations onlyreproduce vegetatively, but someproduce viable seeds. Fruits (follicles)are 35 40 mm long, tapered at bothends and usually paired. They contain1 10 textured seeds, 7 8 mm mats grow to about mhigh and are shade tolerant but willgrow in full sun where there is adequatemoisture. The foliage contains a toxin,but is not generally grazed. Forms withvariegated leaves are also invasive. The mature leaf surface has a waxycuticle that resists uptake of can increase rapidly afterother weeds such as blackberry havebeen controlled, however, whenperiwinkle is removed, other weedscould take its place. Weed identification andsimilar native speciesRelated speciesOther introduced plant species relatedto blue Periwinkle have also escapedfrom gardens in Australia.

7 For example: Lesser Periwinkle or commonperiwinkle (Vinca minor) is similar in appearance but with smaller leavesand flowers and its leaf margins are not hairy. It was also introducedto Australia from Europe and hasescaped in one or two locations inVictoria. Its spread appears to belargely vegetative and it may be a local weed problem. Madagascar Periwinkle (Catharanthusroseus) is a garden escapee that hasbeen nominated as one of the 10worst weeds currently available forsale in Queensland and it has a weedhistory overseas. It prefers sandy soilsand tropical conditions and is wide-spread in coastal regions of northernAustralia. It spreads by seed and hasthe potential to spread further.

8 Itscurrent distribution is New SouthWales, Queensland, NorthernTerritory and Western native climbingspecies No native plants closely resemble blueperiwinkle but examples of native plantswith similar sized leaves and climbinghabit are: Bearded tylophora (Tylophorabarbata) has opposite leaves andsmall purple-red flowers in groups of 3 5 that are rarely seen. It is aclimber, while Periwinkle rarelyclimbs. Its native range is New SouthWales and Victoria. Purple coral pea, happy wanderer or native sarsaparilla (Hardenbergiaviolacea) has alternate, leatheryleaves and clusters of small purple or pink pea flowers. It may climbonto low vegetation but doesn tspread from runners and generally occurs in open conditions in sclerophyll forest and grassywoodlands.

9 Its native range is NewSouth Wales, Queensland, SouthAustralia and Victoria. Mountain silkpod (Parsonsia brownii)has opposite leaves that are elongatedand its flowers are small and creamin colour. It is a climber related toperiwinkle and grows in wet forestsof southeastern Australia. Its nativerange is New South Wales, Tasmaniaand it spreadsPatches of Periwinkle expand by meansof creeping stems that take root at the nodes and tips. New infestationscan establish from plant fragmentswhen broken off and transported by dumping of garden waste, soilmovement or floods. It spreads fromgardens, roadsides, nature strips,firebreaks, fencelines and neglectedrubbish dumps into the bush andalong waterways.

10 Periwinkle iscommonly available as a garden plant,readily propagated from cuttings andpopular as a ground cover. It tends tooverrun garden beds and the excessrunners are thrown out in gardenwaste. Vegetative reproduction is most common, but in some situationsperiwinkle may produce viable seed. Periwinkle Vinca major2 Madagascar Periwinkle (Catharanthus roseus) is a weed of northern Australian coastal areas,related to blue Periwinkle . Photo: Colin WilsonLesser or common Periwinkle (Vinca minor)flowers are 3 cm across. These are smallerthan V. : Dan Tenaglia, Weed Management Guide Periwinkle Vinca majorIn Australia this occurs in riparianrainforest in East Gippsland wherenumerous seedlings may emerge aftermats have been removed.