Andropogon virginicus L.

Title: Andropogon virginicus L.

Scientific Name:

Andropogon virginicus L.

Common Names:

whiskey grass, broomsedge

Source & more images

Habitat:

Native to North America, A. negundo occurs in lowland forest, wet hard wood forest, flood plain forest and riparian areas including ephemeral streams in montane areas and the borders of swamps (Dineva 2005; Gabbe et al 2002; Kolb, Hart & Amundson 1997; Sargent 1949). Outside of its native range it is reported to invade damp to wet sclerophyll forest, sheltered forests and riparian vegetation (Carr, Yugovic & Robinson 1992; Muyt 2001).

Distribution:

Original source via CABI

Invasiveness Assessment

ESTABLISHMENT

1. Germination requirements? Germination for this species occurs in Autumn (Parsons & Cuthbertson 2001).

2. Establishment requirements? The species often occurs on disturbed sites and is reported to be intolerant of shade (Parsons & Cuthbertson 2001; PFAF 2007; Restrepo & Vitousek 2001).

3. How much disturbance is required? The species invades habitats which are considered highly disturbed such as roadsides and overgrazed native pasture (Parsons & Cuthbertson 2001).

GROWTH / COMPETITIVE

4. Life form? Grass; The species is a C4 perennial bunchgrass (Marks & Strain 1989).

5. Allelopathic properties? The species has been found to have significant inhibitory effects on the growth of seedlings of a number of species (Rice 1972). Reported to have some allelopathic properties (Rice 1984).

6. Tolerates herb pressure? The species is reported to have little fodder value and that the dried biomass can present as a fire hazard in late summer, which would indicate that largely the species isn’t consumed (Parsons & Cuthbertson 2001). The species is considered unpalatable and of low forage value (Griffin, Watson & Strachan 1988).

7. Normal growth rate? Reported to have a slow growth rate through winter, plants are then able to grow to 1m high during spring and summer (Parsons & Cuthbertson 2001). The species is therefore considered to have a growth rate equal to that of other grass species.

8. Stress tolerance to frost, drought, w/logg, sal. etc? Reported to occur in ephemeral wetlands (Kirkman & Sharitz 1994). Therefore the species has some tolerance to waterlogging. The species can persist through fire events (D’Antonio, Tunison & Loh 2000). Tolerant of drought (Marks & Strain 1989). Tolerant of heavy metals (Gibson & Risser 1982). Tolerant of frost, Reported to be hardy to zone 6 (-20°C) (PFAF 2007).

REPRODUCTION

9. Reproductive system? The species reproduces sexually producing seed (Parsons & Cuthbertson 2001).

10. Number of propagules produced? Unknown.

11. Propagule longevity? Unknown.

12. Reproductive period? The species is reported to persist in almost pure stands for many years (Rice 1972).

13. Time to reproductive maturity? The species is able to reproduce in its first year (Parsons & Cuthbertson 2001).

DISPERSAL

14. Number of mechanisms? The species seeds are reported to be dispersed externally on animals and with human aided dispersal (Parsons & Cuthbertson 2001).

15. How far do they disperse? This species is spreading into Eastern Victoria through the movement of hay and livestock from NSW, which enables the species to be spread more than 1km (Sexton 2003).

Impact Assessment

RECREATION

1. Restrict human access? As a grass species that only grows to 1m and with no reported barbs or sharp edges, it is thought unlikely that the species would impose any restriction on access (Edgar & Connor 2000; Parsons & Cuthbertson 2001).

2. Reduce tourism? The species is reported to be a weed mainly of roadsides, railway lines and other disturbed places (Edgar & Connor 2000; Parsons & Cuthbertson 2001). It is therefore thought that any impact on tourism and recreation is unlikely

3. Injurious to people? There is no evidence of this reported.

4. Damage to cultural sites? The species is reported to be a weed mainly of roadsides, railway lines and other disturbed places (Edgar & Connor 2000; Parsons & Cuthbertson 2001). It is therefore thought that any impact on cultural sites or infrastructure is unlikely.

ABIOTIC

5. Impact flow? The species can occur in riparian and wetland vegetation, there is no evidence however of it occurring in flowing water and obstructing flow.

6. Impact water quality? The species can occur in riparian vegetation, there is no evidence however of it affecting water quality.

7. Increase soil erosion? The species is a clumping grass species (Parsons & Cuthbertson 2001). It is therefore thought that areas invaded by this species would have a moderate probability of large scale soil movement.

8. Reduce biomass? Unknown; as the species is less palatable and therefore able to accumulate more biomass this may be viewed as increasing biomass (Parsons & Cuthbertson 2001). In Hawaii however the species is associated with reducing overall biomass through alteration of the fire regime (Freifelder & Vitousek 1998).

9. Change fire regime? As the species is less palatable, dried material remains over summer and be a potential fire hazard (Parsons & Cuthbertson 2001). Therefore the species has the potential to moderately increase the fuel load and therefore the fire intensity.

COMMUNITY HABITAT

10(a) Impact on composition of high value EVC? EVC= Riverine Grassy Woodland (V); CMA= Goulburn Broken; Bioreg= Murray Fans; VH CLIMATE The species is reported to be able to dominate within the grass layer (Sorenson 1991).

10(b) Impact on medium value EVC? EVC= Montane Grassy Woodland (D); CMA= North East; Bioreg= Highlands-Northern Fall; VH CLIMATE The species is reported to be able to dominate within the grass layer (Sorenson 1991).

10(c) Impact on low value EVC? EVC= Montane Grassy Woodland (D); CMA= North East; Bioreg= Victorian Alps; VH CLIMATE The species is reported to be able to dominate within the grass layer (Sorenson 1991).

11. Impact on structure? The species is reported to be able to dominate within the grass layer (Sorenson 1991). In Hawaii it is reported to have less impacts on native species than two other grass species (D’Antonio, Tunison & Loh 2000). As the species largely invades grassland, the grass layer is the only one present and so if the species is able to dominate that layer, it is thought to impact upon more than 60% of the flora strata.

12. Effect on threatened flora? Unknown.

FAUNA

13. Effect on threatened fauna? Unknown.

14. Effect on non-threatened fauna? Unknown.

15. Benefits fauna? Grasses species that grows to 1m, may provide limited and short term shelter for species.

16. Injurious to fauna? There is no evidence of this reported.

PEST ANIMAL

17. Food source to pests? Reported to be unpalatable and of low fodder value to stock (Griffin, Watson & Strachan 1988). It may therefore by eaten by grazing pest species however this is thought to be minimal.

18. Provides harbor? Grasses species that grows to 1m, may provide limited and short term shelter for pest species.

AGRICULTURE

19. Impact yield? Has little fodder value, reducing the carrying capacity however as the species is reported to invade poorly managed and or marginal areas of pasture the impact is thought to be minor (Griffin, Watson & Strachan 1988; Parsons & Cuthbertson 2001).

20. Impact quality? Seeds can catch in wool and may therefore be recognised as minor contamination (Parsons & Cuthbertson 2001).

21. Affect land values? The species is reported to invade poorly managed and or marginal areas of pasture (Griffin, Watson & Strachan 1988; Parsons & Cuthbertson 2001). Therefore the value of the property is likely to be devalued for other reasons and therefore the presence of this species is likely to have little impact.

22. Change land use? In changes to management is likely to be limited, such as replacing pasture to more vigorous species instead of native grasses (Parsons & Cuthbertson 2001).

23. Increase harvest costs? In forestry control or suppression of this species may be necessary to enable the establishment of the plantation species (Groninger et al 2004).

24. Disease host/vector? There is no evidence of this reported.

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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 an anonymous donor.

Attachments:

whisky grass via ala.JPG
distribution_map (12).png

referenced by (2)

wra1040: Common Name - W (via whiskey grass)wra825: Common Name - B (via broomsedge)

Article: wra2703 (permalink)
Categories: :wra:a, :wra:inv1, :wra:invmh, :wra:inv2, :wra:inv3, :wra:invml, :wra:inv4, :wra:inv5, :wra:inv6, :wra:inv7, :wra:invm, :wra:inv8, :wra:invh, :wra:inv9, :wra:inv10, :wra:inv11, :wra:inv12, :wra:inv13, :wra:inv14, :wra:inv15, :wra:imp1, :wra:impl, :wra:imp2, :wra:imp3, :wra:imp4, :wra:imp5, :wra:imp6, :wra:imp7, :wra:impml, :wra:imp8, :wra:impm, :wra:imp9, :wra:imp10a, :wra:impmh, :wra:imp10b, :wra:imp10c, :wra:imp11, :wra:imp12, :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: 26 October 2009; 12:28:23 PM AEDT

Author Name: Fariba Moslih
Author ID: moslih