Invasiveness Assessment - Freesia (Freesia alba x Freesia leichtlinii) in Victoria
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 Freesia.
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 - 1 MB)
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: Freesia
Scientific name: Freesia alba x Freesia leichtlinii
| Question | Comments | Rating | Confidence |
| Establishment | |||
| Germination requirements? | ‘Propagate from seed in spring or offsets in fall’ (Burnie et al 1998). ‘Foliage emerges in Winter with flowering and seeding occurring in Spring (Muyt 2001)’. Requires natural seasonal disturbances for germination. | MH | MH |
| Establishment requirements? | Naturalises in woodland (Carr et al 1992) and described as growing ‘amongst tall trees, medium trees... (Florabase WA 2007)’ and as flowering best in light shade (Van der Spuy 1971). ‘The number of freesia plants per m2 was very high in dappled shade, and thins out in direct sunlight (pers. com M. Walsh)’. Likely able to establish under moderate canopy cover. | MH | M |
| How much disturbance is required? | Actively invading intact bushland throughout south eastern Australia (Walsh et al 2007)’. Birds may be responsible for its spread to relatively pristine areas of bushland (EWAN 2006). Invades heathland communities (Carr et al 1992, Lloyd 2007). Able to establish in undisturbed ecosystems, e.g. heathland. | H | MH |
| Growth/Competitive | |||
| Life form? | Geophyte (Carr et al 1992) | ML | MH |
| Allelopathic properties? | Not documented as allelopathic and the ‘horticultural’ literature is relatively extensive. | L | M |
| Tolerates herb pressure? | Freesia is described as a plant that ‘deer may taste but usually do not destroy (Cox 1986)’ - Consumed but not preferred. As a geophyte (Carr et al 1992), it is also likely to recover quickly in response to herbivory due to the presence of corms. | MH | M |
| Normal growth rate? | ‘Foliage emerges in Winter with flowering and seeding occurring in Spring (Muyt 2001)’- As a cormous perennial herb (Flora base 2007), each year it regenerates to its full size. Spreads rapidly by producing abundant corms (Surf Coast 2007). | H | M |
| Stress tolerance to frost, drought, w/logg, sal. etc? | Freesias need some protection from very severe frosts (Van der Spuy 1971). ‘The ability to die back to an underground storage organ during summer enables a plant to avoid fire or drought and tolerate nutrient poor soils (Agric WA 2004)’. Occurs in swamps (Florabase WA 2007). Ability to tolerate drought, fire and moderate frosts and potentially water logging. Tolerance to salinity not found described. | MH | M |
| Reproduction | |||
| Reproductive system | ‘Reproduces by seeds, corms and bulbils (Muyt 2001)’. Both sexual and vegetative reproduction. | H | MH |
| Number of propagules produced? | ‘Freesias are prolific seeders producing several hundred seeds per plant (EWAN 2006)’ - in range of 50-1000 propagules/ plant. | ML | M |
| Propagule longevity? | Propagule longevity not found described. | M | L |
| Reproductive period? | Extensive stands can establish (Muyt 2001)’. Species could form self-sustaining monocultures. | H | MH |
| Time to reproductive maturity? | ‘Clonal offspring become independent from the parent by the next season (Walsh et al 2007)’. Vegetative propagules become separate individuals in under a year. | H | MH |
| Dispersal | |||
| Number of mechanisms? | Seeds and bulbils are dispersed by water, wind, slashing and in garden refuse, soil and during removal (Muyt 2001). | MH | MH |
| How far do they disperse? | Dispersal by machinery and contaminated soil (Muyt 2001, EWAN 2006) could spread propagules greater than 1 km. | H | MH |
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 .