Old Man's Beard
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DEPARTMENT OF PRIMARY INDUSTRIES Old man’s beard Clematis vitalba Victorian Alert Weed Fact Sheet Plant biology Type of weed: Garden escape. Lifeform: Woody perennial vine/climber. Description: Stems: Old man’s beard grows equally as well as a ground covering creeper or as a climbing vine, reaching to the canopy of 30 metre forests. New stem growth is green with six longitudinal ribs on the stem, whilst older stem growth is light brown with longitudinal furrows, and stringy or fl aky bark (Blood 2001). Stems can take root where they touch the ground and create a new plant, while cut stumps left after control are capable of re-sprouting. Leaves: Each leaf is made up of usually fi ve or Image: Dr Amadej Trnkoczy - www.wedinfo.com.au Images: RG & FJ Richardson sometimes seven (rarely three) heart to lance- shaped leafl ets (Blood 2001). Leafl ets are thin Botanical name: Clematis vitalba. and papery, growing from 20-80 mm long Synonyms: None. and 10-40 mm wide. Leafl et edges are bluntly Common name: Old man’s beard. toothed (juvenile leaves) or smooth (adult leaves) Alternatives: Evergreen clematis, traveller’s joy, mile-a-minute. and grow in pairs on opposite sides of the stem. Leaf stalks, rather than the stem, twine around Family: Ranunculaceae. existing undergrowth to help it creep over other Relevant relatives: There are over 200 species of Clematis plants in its path. Leaves fall from the plant including several that are native (some are even rare and during autumn and the plant becomes dormant threatened) to Australia. Clematis aristata (Australian clematis) for winter. is a very similar looking and quite common native climber that also shares the common name of old man’s beard. Another weedy Flowers: Flowers are creamy white or sometimes clematis, C. fl ammula (fragrant clematis), is also sometimes pale green, fragrant and grow to 20-30 mm in misidentifi ed as C. vitalba. diameter. The fl owers are unusual because they do not have true petals; instead, each fl ower has four petal-like sepals. These are usually strongly bent back and oval shaped. The internal fl ower parts are very showy, numerous and look softly hairy. Flowers are in loose clusters that grow from the point where the leaf joins the stem. Fruits: Fruit have a feathery appearance with an oval-shaped centre and contain one seed. Seeds: Seeds are grey coloured and grow to 2.0-2.5 mm long. The densely packed white fl uffy tops form in clusters giving rise to the common name ‘old man’s beard’. Seeds persist on the plant through winter when the leaves drop to expose the beard-like tufts. Roots: Mature plants are supported by a strong taproot reaching several metres in length and fi brous when young becoming woody with age. Weed Alert! Old man’s beard Clematis vitalba Victorian Alert Weeds Importance & impacts Impacts: Ecosystems, waterways and agriculture: What are Victorian Alert Weeds? Old man’s beard is a weed with devastating potential for growth, competition and destruction. Its preferred Victorian Alert Weeds are potential weeds of the habitats are forest edges and stream-side areas, future. They may pose a serious threat to Victoria’s both of which are already under attack from other agricultural and natural assets or could affect destructive forces. Old man’s beard climbs over human health. Some of these weeds are thought everything in its path and can reach the canopy of to occur in small numbers in Victoria and are still even the tallest forests. The massive weight of the eradicable. Other species are yet to reach Victoria, vines can drag trees down to the forest fl oor, reducing but present a serious threat if they were to arrive. a forest to fallen logs and stumps. C. vitalba can alter Weed Spotters help the Department of Primary habitat structure, reduce the diversity of understorey Industries validate the distribution of these weeds. species, impact on animal movement and adversely Weed Spotters are individuals trained to look for affect the visual attractiveness of infested areas. Old and report high priority Weed Alert species in man’s beard may contribute to increased levels of Victoria. They are recruited from the community, soil erosion and increased fl ood damage in riparian government or industry. areas. In New Zealand old man’s beard is a major problem in production foresty. The vines of old man’s beard may also act as a ladder for fi re, helping fl ames reach the canopy and creating higher intensity fi re events. The impacts of this weed on agriculture include the restriction of stock movement and access to water points, increased fencing costs where land Why is this species a is bordered by forest and possible poisoning of livestock if the weed is consumed. Victorian Alert Weed? Social value and health impacts: There are Old man’s beard is a serious weed in several reports of some herbal uses for various parts of old countries around the world and has already man’s beard. However, the risks associated with the naturalised in parts of Australia. In New Zealand, plant include poisoning, dysentery, psychological this species is a serious environmental threat and impacts, allergic reactions and possibly death. could become an equally devastating weed of similar climatic regions of Australia (Richardson et Health hazards: Old man’s beard can be toxic to al 2006). Old man’s beard forms dense, blanket- humans, animals and livestock. Occasional death of like mats, smothering everything in its path. The livestock from eating this plant has been reported thick mats can be several metres deep and when (Roy et al 1998). C. vitalba is poisonous to humans supported can reach canopies of more than 30 if eaten and is capable of causing severe swelling, metres. This dense cover prevents establishment blisters and sores if any skin contact is made with and survival of the native vegetation underneath the plant (Blood 2001). the weed. Control of old man’s beard is complex for it produces large amounts of seed and can Importance: reproduce vegetatively from stem fragments Weed legislative status: Clematis vitalba is not or stems tips. The ability of old man’s beard to declared as a noxious weed in any Australian state rapidly take over large areas is an incentive for or territory. the Weed Spotter network to remain on high alert for this species. Signifi cance of the weed in Australia: In Australia, the infestations of C. vitalba are generally limited to cooler districts. In Victoria there are scattered outbreaks occurring around Melbourne, including the Dandenong ranges (Walsh 1999). Tasmania has major infestations of C. vitalba around Hobart and South Australia has infested sites in the Adelaide Hills (Muyt 2001). Permitted/prohibited entry into Australia: Clematis vitalba plants and seed are permitted entry into Australia, subject to certain conditions. For more information see the AQIS ICON import conditions database at www.daffa.gov.au/aqis/import/icon-icd or call 1800 020 504. Victorian Weed Risk Assessment: Old man’s beard is considered a high risk for Victoria due to its invasive potential, its persistence once established and its ability to degrade natural areas. Old man’s beard has proved to be a devastating menace worldwide, especially in New Zealand. Victoria’s cool climate regions are ideal for an invasion of old man’s beard. Growth & spread Reproduction and dispersal: Old man’s beard Seed bank/propagule persistence: C. vitalba is capable of reproducing sexually via seed and is capable of producing over 100,000 seeds per vegetatively from stem tips and stem fragments, plant in just one year (Muyt 2001). There may be though it prefers the former. Seeds are dispersed over 500 seeds per square metre under a mat of predominantly by wind, water and animals but the C. vitalba, plus thousands of seeds retained on the most likely means of spread is from human activities; plant over winter (Muyt 2001). The soil seed bank dumping garden waste, inadequate removal can last as long as fi ve years and the viability of attempts, on agricultural equipment or carried on fresh seed is greater than 75%, which makes the shoes and clothing. The activities of birds, animals weed a very successful coloniser. and grazing livestock may also contribute to the spread of stem fragments. Origin: Europe, Africa and south-western Asia. Rate of growth and spread: It is a rapidly Where it grows: Old man’s beard prefers moist, growing plant with new shoots growing as much fertile soils and high levels of sunlight, often found as two metres per year and mature plants growing along forest edges and gaps. Its growth slows in up to 10 metres in a season. Old man’s beard can more shaded environments and bursts into life reach reproductive maturity very quickly setting when gaps are created in the canopy. seed after one to three years and sprouting from stem shoots within just one year (ISSG 2005; Blood 2001). A single plant is capable of spreading to cover an area of 180 square metres. Growth calendar Jan Feb Mar April May June July Aug Sept Oct Nov Dec Flowering Seeding Germination Stem growth Dormancy Notes: Growth calendar is broadly based on behaviour and timing of plant changes, either from overseas populations, or from limited populations in Australia. Actual behaviour of plants may differ, depending on climate and geographical location. Weedy distribution in Australia and Introductory pathway to Australia: Given overseas: C. vitalba is a very widespread plant that C. vitalba is established within many countries throughout the world.