Scolymus hispanicus L.

Title: Scolymus hispanicus L.

Scientific name:

Scolymus hispanicus L.

Common name(s):

golden thistle

More images (via ALA)

Habitat: Warm temperate regions where it occurs on dry sites and soils ranging from poor gravels to fertile alluvial loams (Parsons and Cuthbertson, 1992). In Victoria, it has become a weed of grazing land and neglected areas where annual rainfall exceeds 400 mm (Parsons and Cuthbertson, 1992). It is regarded as weed in dryland pastures, vineyards and orchards (Parsons and Cuthbertson, 1992).

Distribution:

Original source via GBIF

Weed Assessment

ESTABLISHMENT

1. Germination requirements? “Seeds germinate in autumn, winter and spring," (Parsons and Cuthbertson, 1992 p.226)

2. Establishment requirements? Established in open areas e.g. Grazing land and neglected areas, (Parsons & Cuthbertson, 1992, p. 225)

3. How much disturbance is required? “In Victoria it has become a weed of grazing land and neglected areas,” (P & C, 1992, p. 225).

GROWTH / COMPETITIVE

4. Life form? Erect perennial herd, and others included but not specified, (P & C, 1992, p. 225).

5. Allelopathic properties? No allelopathic properties described.

6. Tolerates herb pressure? “The rosette leaves are rarely eaten by stock and the aerial growth is never grazed because of the stout spines on the rigid leaves,” (Parsons and Cuthbertson, 1992, p.227)

7. Normal growth rate? Other more rapidly growing thistles e.g. Silybum marianum, Acanthospermum hispidum, (Parsons and Cuthbertson, 1992 p. 230)

8. Stress tolerance to frost, drought, w/logg, sal. etc? Tolerant of drought (occurs in central Victoria), (P & C, 1992, p. 225). (No other information on stress tolerance in P & C 1992).

REPRODUCTION

9. Reproductive system? “Reproducing from a perennial taproot and by seed,”(Parsons and Cuthbertson, 1992 p. 225)

10. Number of propagules produced? “The viability of the seed is about 70%”. Not stated to be numerous or few, (Parsons and Cuthbertson, 1992 p. 226)

11. Propagule longevity? None described.

12. Reproductive period? “The large taproot stays alive and produces new aerial growth each autumn”. herefore assumed to produce propagules for > 3 years, (Parsons and Cuthbertson, 1992 p. 225)

13. Time to reproductive maturity? Seeds germinate autumn/winter/spring develop a rosette in summer without producing a flowering stem flowering stem produced in spring/early summer, flowers in late spring and summer,( P & C, 1992, p. 226)

DISPERSAL

14. Number of mechanisms? See ‘dispersal’ section in P & C (1992 p. 226 & 227).

15. How far do they disperse? As above.

Invasiveness Assessment

RECREATION

1. Restrict human access? An erect, much-branched perennial herb to 90 cm high. It is armed with stout spines on rigid leaves and dense infestations become almost impenetrable to grazing stock. Humans too, would also have difficulty in walking through an infestation; the spines would be a significant nuisance, (Parsons and Cuthbertson, 2001)

2. Reduce tourism? Infestations are known to occur along riverbanks and dense infestations may restrict access to water-based recreational activities, (P & C, 2001).

3. Injurious to people? The stems can remain on the plant after the aerial parts die off in autumn. Spines would be present for much of the year, (Parsons and Cuthbertson, 2001)

4. Damage to cultural sites? The root system is not vigorous and would not affect the structure. Dense patches would have a moderate impact on the visual aesthetic of an area, (Parsons and Cuthbertson, 2001)

ABIOTIC

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

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

7. Increase soil erosion? Although the plant has a robust taproot the aerial parts of the plant die back in summer leaving areas of soil exposed. Moderate probability of large-scale soil movement, (Parsons and Cuthbertson, 2001)

8. Reduce biomass? Not documented as dominating species, it replaces existing biomass.

9. Change fire regime? Dry flower stems break off and are carried by the wind to collect against any obstruction. Large collections of this dry matter may create a minor change in the frequency of fire risk, (Parsons and Cuthbertson, 2001)

COMMUNITY HABITAT

10(a) Impact on composition of high value EVC? EVC=Creekline grassy woodland (E); CMA=North Central; Bioreg=Victorian Riverina; VH CLIMATE potential. “…much of the present Victorian infestation is along the Loddon River downstream [of Smeaton].” New rosettes can grow to 60 cm in diameter, which would restrict growth of other plants. Not recorded in Carr et al (1992). Minor impact in grassland/riparian situations, (P & C, 2001; Carr et al., 1992).

10(b) Impact on medium value EVC? EVC=Grassy dry forest (E); CMA=North Central; Bioreg=Goldfields; VH CLIMATE potential. Impact similar to 10(a) above, however, growth under open forest canopy may restrict population density, (P & C, 2001; Carr et al., 1992).

10(c) Impact on low value EVC? EVC=Heathy dry forest (E); CMA=North Central; Bioreg=Goldfields; VH CLIMATE potential. Impact as in 10(b) above, (P & C, 2001; Carr et al., 1992).

11. Impact on structure? Does not appear to significantly affect the structure of an invaded site. Where it does occur in pastures, it is weedy because animals will not graze the plant. Clumps may prevent the regrowth of desirable forage species, (P & C, 2001).

12. Effect on threatened flora? None described.

FAUNA

13. Effect on threatened fauna? None described.

14. Effect on non-threatened fauna? Grazing animals do not eat the aerial growth because of the stout spines on the rigid leaves, and the spiny nature of the plant discourages animals from grazing near it. Likely to have similar effect on native fauna. Some reduction in habitat, (Parsons and Cuthbertson, 2001).

15. Benefits fauna? No documented benefits.

16. Injurious to fauna? The stout spines present for much of the year may injure animals, (Parsons and Cuthbertson, 2001)

PEST ANIMAL

17. Food source to pests? Not documented.

18. Provides harbor? "Clumps of golden thistle provide effective harbor for rabbits", (Parsons and Cuthbertson, 2001)

AGRICULTURE

19. Impact yield? Stock do not eat the aerial growth and, “avoid grazing close to plants [thus] valuable pasture is neglected.” Dense infestations become almost impenetrable and are likely to reduce carrying capacity, (Parsons and Cuthbertson, 2001)

20. Impact quality? It occurs in vineyards and orchards in part of its native range and does not appear to impact on the quality of harvest, (P & C, 2001).

21. Affect land values? The plant is effectively controlled by mechanical or chemical methods. Until the plant is controlled, grazing areas may be of limited use. May reduce land value slightly, (Parsons and Cuthbertson, 2001)

22. Change land use? Left untreated, the plant would restrict grazing on permanent pasture. It can be controlled by cultivation, so land may have to be used for cropping activity.

23. Increase harvest costs? No know effect on harvesting costs. Assume limited impact.

24. Disease host/vector? None evident.

Feedback

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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:

golden thistle via ala.JPG
Capture.JPG

referenced by (1)

wra1001: Common Name - G (via golden thistle)

Article: wra1971 (permalink)
Categories: :wra:s, :wra:inv1, :wra:invmh, :wra:inv2, :wra:invml, :wra:inv3, :wra:inv4, :wra:invl, :wra:inv5, :wra:inv6, :wra:invh, :wra:inv7, :wra:inv8, :wra:invm, :wra:inv9, :wra:inv10, :wra:inv11, :wra:inv12, :wra:inv13, :wra:inv14, :wra:inv15, :wra:imp1, :wra:impml, :wra:imp2, :wra:imp3, :wra:impmh, :wra:imp4, :wra:impm, :wra:imp5, :wra:imp6, :wra:imp7, :wra:imp8, :wra:imp9, :wra:imp10a, :wra:imp10b, :wra:imp10c, :wra:imp11, :wra:imp12, :wra:imp13, :wra:imp14, :wra:imp15, :wra:imph, :wra:imp16, :wra:imp17, :wra:impl, :wra:imp18, :wra:imp19, :wra:imp20, :wra:imp21, :wra:imp22, :wra:imp23, :wra:imp24
Date: 13 October 2009; 9:50:32 AM AEDT

Author Name: Niharika Anand
Author ID: anandn