Cynara cardunculus L.

Title: Cynara cardunculus L.

Scientific Name:

Cynara cardunculus L.

Common Names:

artichoke thistle, Spanish artichoke

Source & more images (via ALA)

Habitat: Warm temperate regions with a dominant winter rainfall in the 500 to 750 mm of annual rainfall belt, and preferring black basalt soils in Victoria (Parsons and Cuthbertson, 1992). Artichoke thistle is an important weed of poorer pastures, occasionally lucerne and crops, and once established usually dominates the vegetation of an area (Parsons and Cuthbertson, 1992). It is also invades lowland grassland and grassy woodland, and riparian vegetation (Carr et al. 1992).

Distribution:

Original source via CABI

Invasiveness Assessment

ESTABLISHMENT

1. Germination requirements? “Seeds may germinate at any time of the year but most do so after autumn rain”. (Parsons and Cuthbertson, 1992)

2. Establishment requirements? Requires ‘open’ areas e.g. pasture, gardens, wasteland, roadsides, vacant allotments. (Parsons and Cuthbertson, 1992; K& J, 1997)

3. How much disturbance is required? Establishes in minor disturbed ecosystems (e.g. riparian, grassland) and well-established pastures. (Parsons and Cuthbertson, 1992; Carr et al.,1992)

GROWTH / COMPETITIVE

4. Life form? Perennial herb. (Parsons and Cuthbertson, 1992; Carr et al.,1992)

5. Allelopathic properties? “The spiny nature of the plant deters sheep and cattle from grazing on heavy infestations but, when hungry, animals will eat the leaves”. (Parsons and Cuthbertson, 1992)

6. Tolerates herb pressure? “The spiny nature of the plant deters sheep and cattle from grazing on heavy infestations but, when hungry, animals will eat the leaves”. (Parsons and Cuthbertson, 1992)

7. Normal growth rate? Can choke out or dominate vegetation of an area once established. (NSW Dept.. Ag., 1962; Parsons and Cuthbertson, 1992)

8. Stress tolerance to frost, drought, w/logg, sal. etc? Tolerance to salinity, presumably also drought (occurs in Ciza & Kalubia, Egypt & Australia). Water logging (occurs in irrigated and riparian areas)? (Wernli & Tames, 1984; Giushniani et al., 1999; Carr et al., 1992)

REPRODUCTION

9. Reproductive system Reproducing from a perennial taproot and by seed. (Parsons and Cuthbertson, 1992)

10. Number of propagules produced? Approximately 16 inflorescence per plant x 100 florets per inflorescence x 1 seed per floret = approximately 1,600 seeds. About 16 heads on each plant but occasionally > 50 or more inflorescence 8 less florets. (Parsons and Cuthbertson, 1992)

11. Propagule longevity? not known

12. Reproductive period? “Individual plants may live for many years”. Also, can form monocultures. (See picture in Parsons and Cuthbertson, 1992 p. 214). Carr et al. (1992) also states that the plant forms ‘medium to large infestations’.

13. Time to reproductive maturity? “Plants may flower in the first year but generally flowering is delayed until the second summer”. (Parsons and Cuthbertson, 1992)

DISPERSAL

14. Number of mechanisms? Mostly seed dispersal – wind, animals, water, mud and birds. (Parsons and Cuthbertson, 1992)

15. How far do they disperse? Seeds are usually blown within a few metres of the birds, plants. Animals, particularly birds and water are however likely to spread seeds farther. Small birds feed on seeds, perhaps dispersing seed > 200 m. (Parsons and Cuthbertson, 1992)

Impact Assessment

RECREATION

1. Restrict human access? Generally associated with agriculture, C. cardunculus does invade native grasslands and grassy woodlands, and riparian vegetation. Large populations can develop in disturbed areas, and with the tall growth habit (to 2 m) and spines on the leaves, the plant would present a high level of nuisance to humans. (Muyt, 2001; Carr et al., 1992)

2. Reduce tourism? The obvious presence of the weed, dense growth and prickly nature would affect recreational activities, and no doubt lead to visitor complaints.(Muyt, 2001)

3. Injurious to people? The plant has spines for most of the year. “The plant is reported to cause contact dermatitis in some people.” (Parsons and Cuthbertson, 2001)

4. Damage to cultural sites? “Wherever it occurs in the world, it becomes a very visible component of the flora.” In dense infestations it would create a negative visual effect. (Parsons and Cuthbertson, 2001)

ABIOTIC

5. Impact flow? Terrestrial sp. (Parsons and Cuthbertson, 2001)

6. Impact water quality? Terrestrial sp. (Parsons and Cuthbertson, 2001)

7. Increase soil erosion? Large populations eliminate most indigenous flora and, after flowering in summer, the aerial parts of the plant die off. However, the dense population would provide suitable soil stability resulting in little effect on large-scale soil movement. (McLaren, D. pers com. n.d).

8. Reduce biomass? In disturbed areas large populations can eliminate ground flora and seriously impede overstorey regeneration. Invades native grasslands and grassy woodlands, and riparian vegetation. Invader replaces biomass. (Muyt, 2001)

9. Change fire regime? Although the aerial parts of the plant die off in summer, the flowering stems remain standing for several months. These are dry and woody and may contribute to an increase in the frequency of fire. (Parsons and Cuthbertson, 2001)

COMMUNITY HABITAT

10(a) Impact on composition of high value EVC EVC=Plains grassy woodland (E); CMA=Corangamite; Bioreg=Victorian Volcanic Plain; VH CLIMATE potential. “…once established, it dominates the vegetation of an area. Large plants with their dense foliage shade most pasture species as well as drawing moisture and nutrients from the soil.” Serious impact on grasses/forbs. (Parsons and Cuthbertson, 2001)

10(b) medium value EVC EVC=Herb-rich heathy woodland (E); CMA=Glenelg Hopkins; Bioreg=Dundas Tablelands. VH CLIMATE potential. “…once established, it dominates the vegetation of an area. Large plants with their dense foliage shade most pasture species as well as drawing moisture and nutrients from the soil.” Serious impact on species within the lower stratum. (Parsons and Cuthbertson, 2001)

10(c) low value EVC EVC=Heathy woodland (E); CMA=Port Phillip; Bioreg=Gippsland Plain; VH CLIMATE potential. “…once established, it dominates the vegetation of an area. Large plants with their dense foliage shade most pasture species as well as drawing moisture and nutrients from the soil.” Serious impact on species within the lower stratum. (Parsons and Cuthbertson, 2001)

11. Impact on structure? In disturbed areas large populations can eliminate ground flora and seriously impede overstorey regeneration. Major effect lower storey, minor impact on mid and overstorey species. (Muyt, 2001)

12. Effect on threatened flora? not assessed

FAUNA

13. Effect on threatened fauna? not assessed

14. Effect on non-threatened fauna? In natural environments it is most likely to establish dense infestations in disturbed areas. It also tends to colonise in medium to large populations. In those situations, the presence of the weed would have a significant impact on the habitat of non-threatened fauna. Spiny nature of plant would deter grazing. (Parsons and Cuthbertson, 2001; Muyt, 2001; Carr et al., 1992)

15. Benefits fauna? “Small birds feed on the seeds.” Bird species not mentioned. Limited food source. (Parsons and Cuthbertson, 2001)

16. Injurious to fauna? The plant has spines for most of the year. Potential for injury. (Parsons and Cuthbertson, 2001)

PEST ANIMAL

17. Food source to pests? “Small birds feed on the seeds.” Bird species not mentioned. Limited food source. Mice are known vectors for seed dispersal. (Parsons and Cuthbertson, 2001)

18. Provides harbor? No evidence of plant providing harbor for pest animals.

AGRICULTURE

19. Impact yield? In permanent pastures C. cardunculus can dominate the vegetation. “Its spiny nature deters sheep and cattle from grazing on heavy infestations but, when hungry, animals will eat the leaves and survive on them.” “It has low nutrient value and may cause stomach impaction and mechanical injuries.” Potential for high impact on yield. (Parsons and Cuthbertson, 2001)

20. Impact quality? No recorded impact on quality.

21. Affect land values? Heavily infested pasture requires mechanical and/or chemical control to re-establish desired pasture spp. Presence of weed would have some minor influence on land value. (Parsons and Cuthbertson, 2001)

22. Change land use? Control practices can be incorporated into existing pasture use. Change in land use would not be required. (Parsons and Cuthbertson, 2001)

23. Increase harvest cost? In Western Australia, the weed has occurred in cropping situations where it, "...impedes harvesting." (Dept. of Ag. WA)

24. Disease host/vector? None evident.

Feedback

Do you have additional information about this plant that will improve the quality of the assessment? If so, we would value your contribution.

Assessment ratings originally made by the Victorian Department of Primary Industries.

The entry of this assessment was made possible through the generous support of The Weed's Network.

Attachments:

tn_artichoke_thistle_plant.jpg
artichoke thistle via ala.JPG
distribution_map (23).png

referenced by (2)

wra1033: Common Name - S (via Spanish artichoke)wra702: Common Name - A (via artichoke thistle)

Article: wra10 (permalink)
Categories: :wra:c, :wra:inv1, :wra:invh, :wra:inv2, :wra:invml, :wra:inv3, :wra:invmh, :wra:inv4, :wra:invl, :wra:inv5, :wra:inv6, :wra:inv7, :wra:inv8, :wra:inv9, :wra:inv10, :wra:inv11, :wra:invm, :wra:inv12, :wra:inv13, :wra:inv14, :wra:inv15, :wra:imp1, :wra:impmh, :wra:imp2, :wra:imph, :wra:imp3, :wra:imp4, :wra:impml, :wra:imp5, :wra:impl, :wra:imp6, :wra:imp7, :wra:imp8, :wra:imp9, :wra:imp10a, :wra:imp10b, :wra:imp10c, :wra:imp11, :wra:imp12, :wra:impm, :wra:imp13, :wra:imp14, :wra:imp15, :wra:imp16, :wra:imp17, :wra:imp18, :wra:imp19, :wra:imp20, :wra:imp21, :wra:imp22, :wra:imp23, :wra:imp24
Date: 13 May 2009; 3:43:52 PM AEST

Author Name: David Low
Author ID: adminDavid