Invasiveness Assessment - Tutsan (Hypericum androsaemum) in Victoria (Nox)
Back | Table | Feedback
Plant invasiveness is determined by evaluating a plant’s biological and ecological characteristics against criteria that encompass establishment requirements, growth rate and competitive ability, methods of reproduction, and dispersal mechanisms.
| Each characteristic, or criterion, is assessed against a list of intensity ratings. Depending upon information found, a rating of Low, Medium Low, Medium High or High is assigned to that criterion. Where no data is available to answer a criterion, a rating of medium (M) is applied. A description of the invasiveness criteria and intensity ratings used in this process can be viewed here. |
The following table provides information on the invasiveness of Tutsan.
A more detailed description of the methodology of the Victorian Weed Risk Assessment (WRA) method can be viewed below:
Victorian Weed Risk Assessment (WRA) method (PDF - 630 KB)
Victorian Weed Risk Assessment (WRA) method (DOC - 1026 KB)
To view the information PDF requires the use of a PDF reader. This can be installed for free from the Adobe website (external link).
Common Name: Tutsan
Scientific name: Hypericum androsaemum
| Question | Comments | Reference | Rating |
| Establishment | |||
| Germination requirements? | Seeds germinate in autumn. | P & C (1992) | MH |
| Establishment requirements? | Can tolerate shade (moderate canopy) cover. | P & C (1992) | MH |
| How much disturbance is required? | “Establishes in virtually indisturbed bushland”. | P & C (1992) | H |
| Growth/Competitive | |||
| Life form? | Erect shrub. Other. | P & C (1992) | L |
| Allelopathic properties? | None described. |  | L |
| Tolerates herb pressure? | “Unpalatable and rarely eaten”. | P & C (1992) | MH |
| Normal growth rate? | Whole hillsides may be covered to the exclusion of most other vegetation. Competes strongly with native species. | P & C (1992) | H |
| Stress tolerance to frost, drought, w/logg, sal. etc? | Tolerant of frost, (occurs in Mansfield, Blue Mountains- Australia: Britain, etc), water logging? (occurs in riparian vegetation). | P & C (1992) Clapham et al (1952) Carr et al (1992) | ML |
| Reproduction | |||
| Reproductive system | Reproducing by seed. | P & C (1992) | ML |
| Number of propagules produced? | Produce “large numbers “ of seeds. > 20 fruits per plant x 100 seeds - > 2,000 seeds per plant. | P & C (1992) | H |
| Propagule longevity? | ? | | M |
| Reproductive period? | Forms dense monocultures (see P & C 1992 p. 386). “Widespread, medium to large populations”. | P & C (1992) Carr et al (1992) | H |
| Time to reproductive maturity? | “Plants do not flower until they are 18 months or two years old”. | P & C (1992) | MH |
| Dispersal | |||
| Number of mechanisms? | Small seeds readily contaminate agricultural produce, vehicles, machinery, animals, water and mud. Also bird dispersed. | P & C (1992) | H |
| How far do they disperse? | Bird dispersed. | | H |
Feedback
Do you have additional information about this plant that will improve the quality of the assessment?
If so, we would value your contribution. Click on the link to go to the feedback form.
© State of Victoria (Agriculture Victoria) 1996 - .
This work, Victorian Resources Online, is licensed under a Creative Commons Attribution 4.0 licence. You are free to re-use the work under that licence, on the condition that you credit the State of Victoria (Agriculture Victoria) as author, indicate if changes were made and comply with the other licence terms.
The licence does not apply to ‘branding’ or some ‘images or photographs’ that may be owned by third parties. We ask you to seek prior approval to use images using the VRO feedback form. Access to higher quality images can also be provided on request.
This page was last updated on .