Genista linifolia L.

Title: Genista linifolia L.

Scientific name:

Genista linifolia L.

Common name(s):

Flax-leaved broom, genista, Mediterranean broom

Source & more images (via ALA)

Habitat: Warm-temperate regions, growing on slightly acidic soils in areas with moderate rainfall (Parsons and Cuthbertson 1992). Flax-leaved broom invades dry coastal vegetation, heathland and heathy woodland, lowland grassland and grassy woodland, dry sclerophyll forest and woodland, damp sclerophyll forest and riparian vegetation (Carr et al 1992).

Distribution:

Original source via GBIF

Invasiveness Assessment

ESTABLISHMENT

1. Germination requirements? Seeds germinate in autumn and spring. (P & C, 1992)

2. Establishment requirements? Can establish under moderate canopy cover understorey shrub in many vegetation formations. (Carr et al, 1992; Qarro & Hracherrass, 1995)

3. How much disturbance is required? Establishes in minor disturbed natural ecosystems/healthy natural ecosystems, e.g. heathland, dry and damp sclerophyll forest and riparian vegetation. (Carr et al, 1992)

GROWTH / COMPETITIVE

4. Life form? Erect evergreen leguminous shrub. (P & C, 1992)

5. Allelopathic properties? None described.

6. Tolerates herb pressure? “Little grazed” consumed but not preferred. (P & C, 1992)

7. Normal growth rate? “Plants develop slowly during the first year. They do not flower until at least two years old”. “A rapid” spreader which can crowd out pasture”. (Dept. Crown Lands and Survey. Vic. 1982). (P & C, 1992)

8. Stress tolerance to frost, drought, w/logg, sal. etc? Tolerant of drought, water logging? (Occurs in riparian vegetation): fire (regenerates prolifically from soil-stored seed after fire). (Gonzalez & Ortiz, 1996; Carr et al, 1992; RPPSWG 1991)

REPRODUCTION

9. Reproductive system? Reproducing by seed. (P & C, 1992)

10. Number of propagules produced? Bush contains > 2000 flowers (see pic. P & C 1992 p. 476 & 477). Therefore > 2000 seeds. (P & C, 1992)

11. Propagule longevity? ?

12. Reproductive period? Forms impenetrable thickets (not really monocultures though). However, as it is a shrub it is likely to produce propagules for between 3-> 10 years. (P & C, 1992)

13. Time to reproductive maturity? Plants do not flower until at least two years old. (P & C, 1992)

DISPERSAL

14. Number of mechanisms? Seeds are ejected some distance from pods in summer. Seeds are spread by vehicles, could disperse > 200 m, produce, mud, etc. (P & C, 1992)

15. How far do they disperse? Most seeds would be ejected < 20 m.

Impact Assessment

RECREATION

1. Restrict human access? Evergreen plant that can dominate the shrub canopy and grow to 3 metres high and wide. It grows in a variety of natural habitats including forest margins and riparian areas. It was used as a hedge plant, and dense infestations would present a significant barrier to people. (Muyt, 2001)

2. Reduce tourism? Infestations in natural ecosystems would restrict some recreational activities. (Muyt, 2001)

3. Injurious to people? The seeds are highly poisonous. (Blood, 2001)

4. Damage to cultural sites? The root system is not vigorous, thus, the plant would not cause structural damage to sites. “Brooms are highly invasive, commonly invading disturbed bushland margins before expanding into less disturbed areas.” The presence of G. linifolia would be very noticeable particularly during flowering, which would present a moderate negative visual impact. (P & C, 2001; Muyt, 2001)

ABIOTIC

5. Impact flow? Terrestrial species. (P & C, 2001)

6. Impact water quality? Terrestrial species. (P & C, 2001)

7. Increase soil erosion? An evergreen plant that provides extensive vegetative cover; branched taproot with numerous shallow lateral roots. This plant would not contribute to soil erosion. (Muyt, 2001)

8. Reduce biomass? Generally invades disturbed bushland areas. With its growth habit biomass may increase. (Muyt, 2001)

9. Change fire regime? G. monspessulana is a fire hazard in forest areas where it can form “an inflammable understorey at the edge of forests where fires are most likely to start.” G. linifolia is likely to be similar. High potential to change the frequency of fire risk. (P & C, 2001)

COMMUNITY HABITAT

10(a) Impact on composition of high value EVC? EVC=Grassy woodland (E); CMA=East Gippsland; Bioreg=Gippsland Plain; VH CLIMATE potential “Infestations shade and crowd out smaller shrubs and ground-flora species, eventually dominating the shrub canopy and severely impeding overstorey regeneration.” Major displacement of some species within low to mid strata. (Muyt, 2001)

10(b) Impact on medium value EVC? EVC=Montane grassy woodland (D); CMA=East Gippsland; Bioreg=Highlands – Southern Fall; VH CLIMATE potential Impact as in 10(a) above. (Muyt, 2001)

10(c) Impact on low value EVC? EVC=Riparian forest (LC); CMA=East Gippsland; Bioreg=Highlands – Southern Fall; VH CLIMATE potential Impact as in 10(a) above. (Muyt, 2001)

11. Impact on structure? “Infestations shade and crowd out smaller shrubs and ground-flora species, eventually dominating the shrub canopy and severely impeding overstorey regeneration.” Major impact on lower and mid-storey species. (Muyt, 2001)

12. Effect on threatened flora?

FAUNA

13. Effect on threatened fauna?

14. Effect on non-threatened fauna? Its capacity to invade a broad range of vegetative communities including grasslands, woodlands, heathlands, forests and riparian areas and its potential to dominate indicates the plant is likely to have a major impact on the food sources of native fauna. “Dense thickets exclude most other plants and thus affect the carrying capacity.” It is widespread in medium to large populations. (Muyt, 2001; P & C, 2001; Carr et al 1992)

15. Benefits fauna? No recorded benefits. The plant may provide harbor for some species. (P & C, 2001; Blood, 2001)

16. Injurious to fauna? Seeds are believed to be toxic. (Blood, 2001).

PEST ANIMAL

17. Food source to pests? Not known as a food source to pest animals.

18. Provides harbor? It “affords cover for pest animals such as rabbits.” (P & C, 2001)

AGRICULTURE

19. Impact yield? Its effect in agricultural situations is limited as it mostly occurs in poorer pastures. In these situations, however, “it forms dense thickets, which exclude most other vegetation and thus affect the carrying capacity.” It would have at least a minor impact on yield. (P & C, 2001)

20. Impact quality? The plant reproduces sexually and takes about two years to reach sexual maturity. In cropping situations the plant would not develop sufficiently to produce seed that may contaminate seed crops. (Muyt, 2001)

21. Affect land values? On arable land control is easily effected by mechanical means. Not likely to affect land value. (P & C, 2001)

22. Change land use? Not a serious weed of agriculture. Control is easily effected by mechanical means. (P & C, 2001)

23. Increase harvest costs? No evidence it increases harvest costs.

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 an anonymous donor.

Attachments:

tn_flax_leaved_broom.jpg
genista via ala.JPG
Capture.JPG

referenced by (2)

wra1009: Common Name - M (via Mediterranean broom)wra1000: Common Name - F (via flax-leaved broom)

Article: wra1710 (permalink)
Categories: :wra:g, :wra:inv1, :wra:invmh, :wra:inv2, :wra:inv3, :wra:invh, :wra:inv4, :wra:inv5, :wra:invl, :wra:inv6, :wra:inv7, :wra:inv8, :wra:invml, :wra:inv9, :wra:inv10, :wra:inv11, :wra:invm, :wra:inv12, :wra:inv13, :wra:inv14, :wra:inv15, :wra:imp1, :wra:impmh, :wra:imp2, :wra:imp3, :wra:imph, :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: 5 October 2009; 4:12:24 PM AEDT

Author Name: Jessica Mackay
Author ID: mackayj