Pennisetum setaceum (Forrsk.) Chiov.

Title: Pennisetum setaceum (Forrsk.) Chiov.

Scientific Name: Pennisetum setaceum (Forrsk.) Chiov.

Common Name: fountain grass

Source

Habitat: P. setaceum in its native range establishes in open, scrubby and dry habitats (Flordata, Drake and Griffiths, 1992). It is a weed of pastures and alongside railway lines and roads (Johnson) and can grow in rock crevices and pavement cracks (CDFA). It grows in tropical to semi arid areas and prefers exposed, dry habitats, particularly rocky areas but can also grow in sandy soils such as coastal grasslands and coastal sage scrub (Johnson; CDFA; Clayton, 1970). In southern California it invades grasslands, shrublands warm deserts, canyons and roadsides (NPCI, CDFA). Is one of Hawaii’s most invasive horticultural plants (Poulin et al., 2005).

Distribution:

Invasiveness Assessment

ESTABLISHMENT

1. Germination requirements? Flowers January to April (Walsh and Entwisle, 1996). In order to sprout it needs open space and sunshine with a warm temperature (Medio ambient Canarias). Under conditions of low water availability, invasive fountain grass had lower seedling survival compared with the native grass (Goergen and Daehler, 2001). Germination requires natural seasonal disturbance such as seasonal rainfall.

2. Establishment requirements? P. setaceum productivity decreases with decreasing light availability (Litton et al, 2006) hence survives well in open sites. Requires full sun but tolerates partial shade (Floridata). However under conditions of low water availability, invasive fountain grass had lower seedling survival compared with the native grass (Goergen and Daehler, 2001). The rate of invasiveness and establishment is somewhat influenced by the amount of rainfall and moisture (Poulin et al., 2005). However it is a species that is native in arid areas. Furthermore in the United States it is limited to fairly dry areas where the median rainfall is less than 127 cm (NCPI). Making it a known serious weed in many dry habitats in the States (NPCI). In its native range it establishes in open, scrubby habitats (Flordata). P. setaceum requires open space and access to direct light for successful establishment.

3. How much disturbance is required? In its native range P. setaceum establishes in open, scrubby habitats (Flordata). Outside its native range P. setaceum is a weed of pastures and alongside railway lines and roads (Johnson) and can grow in rock crevices and pavement cracks (CDFA). It grows in tropical to semi arid areas and prefers exposed, dry habitats, particularly rocky areas but can also grow in sandy soils such as coastal grasslands and coastal sage scrub (Johnson; CDFA; Clayton, 1970). In southern California it invades grasslands, shrublands warm deserts, canyons and roadsides (NPCI, CDFA). The species is able to establish in minimal disturbed natural ecosystems such as grasslands.

GROWTH / COMPETITIVE

4. Life form? Perennial grass up to 1 m high (Walsh and Entwisle, 1996; Poulin et al, 2005).

5. Allelopathic properties? In all of the literature there was no reference made to allelopathic properties of this plant.

6. Tolerates herb pressure? Fountain grass is of little grazing value due to its coarse rough leaves (Johnson). A study conducted by Blackmore and Vitousek (2000) investigated cattle grazed P.setaceum. In Hawaii cattle eat fountain grass only when no other grass is available (California Uni). The grass is fed to horses during winter, although not a good pasture grass, still it is eaten by goats and camels (Sherif and Siddiqi, 1988; NPCI). The species is consumed but not a preferred species.

7. Normal growth rate? Growth rate of the species has been described as being fast (Gilman, 1999) that can live to up to 20 years (Johnson). Fountain grass out competes and grows faster than some native grass (Litton et al, 2006). It is an aggressive species that out competes native plants (NPCI). The species exhibits rapid growth rate that will exceed most other species.

8. Stress tolerance to frost, drought, w/logg, sal. etc? Tolerant of high temperatures, high humidity, high wind, drought and acidic to alkaline soils (Floridata). Extremely drought tolerant, established plants thrive in areas where annual rainfall is less than 127 cm of rain annually (Floridata, NPCI). However the species does not survive prolonged low temperatures (Drake, 1994) and does not tolerate saline conditions (CDFA). The species is well adapted to fire and can recover to pre burn density (D’Antonio and Vitousek, 1992). P. setaceum is highly tolerant of at least two and susceptible to two.

REPRODUCTION

9. Reproductive system? Can reproduce asexually and reproduce by seeds following pollination (Simpson and Bashaw, 1969) by either fertilized or unfertilized seeds (Simpson and Bashaw, 1969). The species can be propagated from seed and it will self sow in warm climates. Most cultivars do not produce seeds; they are propagated by dividing the root clumps (Floridata). The plant can reproduce by seed naturally and be cultivated vegetatively.

10. Number of propagules produced? An average of 100 seeds per plant was measured in a trial conducted by Poulin et al (2007) under greenhouse conditions.

11. Propagule longevity? Seeds that were kept in the laboratory for 18 months decreased in viability from 80 to 44 percent (Tunison, 1992). Can remain viable in soil for up to six years or longer (Tunison, 1992; NPCI, PCA, 2005). Therefore greater than 25% of seeds can survive 5-10 years in the soil.

12. Reproductive period? P. setaceum can form monospecific stands (Tunison, 1992) furthermore individual plants may live up to 20 years or more (CDFA).

13. Time to reproductive maturity? No information exists on time to reproductive maturity on this species.

DISPERSAL

14. Number of mechanisms? Primarily wind dispersed (NPCI). Mainly spread by humans and wind, also animals and water (Poulin et al 2007). It is readily dispersed by vehicles, humans, wind, water and possibly birds (Tunison, 1992). The propagules are spread by wind, water and possibly animals and also humans.

15. How far do they disperse? Seeds can be dispersed greater distances by water, vehicles, livestock and humans (NPCI). New infestations were seen to establish one quarter of a mile upstream from other infestations (SDCP). Therefore it is very likely that at least one propagule will disperse greater than one kilometre.

Impact Assessment

RECREATION

1. Restrict human access? Robust tussock forming perennial about 1 m high with creeping underground stems with inflorescences 30 cm long (Richardson et al., 2006). Densely tufted perennial grass growing to 1.5 m (Groves et al, 2005, Johnson) that can form dense monoculture stands that can exclude all other plants (Johnson; Poulin et al, 2005). Once the plant forms dense infestations it is likely to be of high nuisance value impeding both pedestrian and vehicular access.

2. Reduce tourism? Flower heads are 8-30 cm long (Walsh and Enwisle, 1996) and are a long feathery spike which makes it attractive for garden cultivations (Groves et al., 2005). In a dry environment it remains attractive and in humidity it flowers constantly and bears fruits throughout the whole year (Medio ambiente Canarias, 1999). It makes a dramatic statement anywhere in the landscape (Floridata). Furthermore it is a densely tufted perennial grass growing to 1.5 m (Groves et al., 2005, Johnson) that can form dense stands that can exclude all other plants (Johnson). Its attractive flowerhead is obvious and is likely to have major impacts on aesthetics, however visitors may judge the display as aesthetically pleasing. Its ability to dominate and densely invade landscapes indicates that the plant is likely to have significant impact on recreation activities if invading such areas.

3. Injurious to people? No reports of the plant being injurious to people (Walsh and Enwisle, 1996, Richardson et al, 2006).

4. Damage to cultural sites? Flowerheads are 8-30 cm long (Walsh and Entwisle, 1996) and are a long feathery spike which makes it attractive for garden cultivations (Groves et al., 2005). In a dry environment it remains attractive and in humidity it flowers constantly and bears fruits throughout the whole year (Medio ambiente Canarias, 1999). It makes a dramatic statement anywhere in the landscape (Floridata). On this basis infestation of this plant on cultural sites it is likely to have a moderate visual effect.

ABIOTIC

5. Impact flow? This species is terrestrial it is unlikely to have an affect on water flow.

6. Impact water quality? This species is terrestrial it is unlikely to have an affect on water quality.

7. Increase soil erosion? The species is rhizomatous, forming large tussocks (Walsh and Entwisle, 1996) however it is shallow rooted (Litton et al, 2006). The plant has been noted as being good for erosion control (Floridata) and has been used for soil stabilisation (Johnson). However the plant is an aggressive species that can displace native species forming dense stands (Johnson) but maintains soil integrity by replacing existing species.

8. Reduce biomass? In a study conducted by Litton et al. (2006) the site used was formerly a forested site that has been converted to P. setaceum dominated grassland. The presence of a dense P. setaceum understorey will lead to the eventual conversion of remaining forest fragments to grasslands without active control of P. setaceum (Litton et al., 2006). Formerly extensive Heteropogon grasslands have been reduced to remnants surrounded by Pennisetum (Carino and Daehler, 2002). The species can destroy dry forests through increased fire frequency (Poulin et al, 2005). Therefore, this species has the capacity to significantly decrease the biomass of areas by replacing forested systems with grasslands.

9. Change fire regime? Alters natural fire regime in Hawaii, it raises fuel load, which increases the intensity and spread of a fire subsequently threatening native flora (NPCI). Fountain grass has been noted to produce 51% more total biomass than native Hawaiian grass (California Uni) hence increasing fuel loadings (Tunison, 1992). Subsequently increasing the intensity and spread of a fire (Lloyd, 1992; PCA, 2005). P. setaceum produces large quantities of fine fuels that promote fire (Litton et al., 2006). The natural fire regime in Hawaii has been markedly altered by the rapid spread of alien grasses particularly P. setaceum amongst others (Smith and Tunison, 1992). Fountain grass turns brown and dry in the winter and becomes extremely flammable (Floridata). Dense stands are extreme fire hazard. By enhancing the fuel load it endangers native plant communities that are not fire tolerant (California Uni). Fires fuelled by fountain grass impact on ground- nesting birds and terrestrial animals as well (California Uni). P. setaceum is likely to greatly change the frequency and/or intensity of fire.

COMMUNITY HABITAT

10(a) Impact on composition of high value EVC? EVC= Plains Grassland (E) ; CMA=Mallee; Bioregion= Lowan Mallee; VH CLIMATE potential. The plant typically forms dense monospecific stands in the understorey that can exclude all other plants (Johnson; Tunison, 1992). Has exhibited universally superior competitive performance compared to native species (Daehler, 2003). The presence of a dense P. setaceum understorey will lead to the eventual conversion of remaining forest fragments to grasslands without active control of P. setaceum (Litton et al., 2006). The species is aggressive and extremely competitive and is likely to dominant and displace existing vegetation in the lower stratum.

10(b) Impact on medium value EVC? EVC= Shallow Sands Woodland (D) ; CMA=Wimmera; Bioregion= Lowan Mallee; VH CLIMATE potential. The plant typically forms dense monospecific stands in the understorey that can exclude all other plants (Johnson; Tunison, 1992). Has exhibited universally superior competitive performance compared to native species (Daehler, 2003). The presence of a dense P. setaceum understorey will lead to the eventual conversion of remaining forest fragments to grasslands without active control of P. setaceum (Litton et al., 2006). The species is aggressive and extremely competitive and is likely to dominant and displace existing vegetation in the lower stratum.

10(c) Impact on low value EVC? EVC= Coastal Dune Scrub (C) ; CMA=Glenelg Hopkins; Bioregion= Glenelg Plain; VH CLIMATE potential. The plant typically forms dense monospecific stands in the understorey that can exclude all other plants (Johnson; Tunison, 1992). Has exhibited universally superior competitive performance compared to native species (Daehler, 2003). The presence of a dense P. setaceum understorey will lead to the eventual conversion of remaining forest fragments to grasslands without active control of P. setaceum (Litton et al., 2006). The species is aggressive and extremely competitive and is likely to dominant and displace existing vegetation in the lower stratum.

11. Impact on structure? It is a highly aggressive, fire adapted coloniser that readily out competes native plants, prevents further regeneration of native trees and rapidly re establishes after burning (NPCI; Litton et al, 2006). The plant typically forms dense monospecific stands in the understorey that can exclude all other plants (Johnson; Tunison, 1992) and has done so in Hawaiian lowland dry forests (Litton et al., 2006). Has exhibited universally superior competitive performance compared to native species (Daehler, 2003). As a result enhancing fuel load thus endangering native woody plant communities it invades (Tunison, 1992). Hence altering existing native ecosystem structure. It is likely that the strong negative impacts associated with invasive grasses are likely to impact on the long term structure of native tree populations (Litton et al., 2006).Infestations of this species are likely to have a major effect on <60% of the floral strata.

12. Effect on threatened flora? The effect on threatened flora is unknown.

FAUNA

13. Effect on threatened fauna? The effect on threatened flora is unknown.

14. Effect on non-threatened fauna? The plant typically forms dense monospecific stands in the understorey that can exclude all other plants (Johnson; Tunison, 1992). The presence of a dense P. setaceum understorey will lead to the eventual conversion of remaining forest fragments to grasslands without active control of P. setaceum (Litton et al., 2006). Translating to a loss of habitat for many terrestrial and avian species. Fires fuelled by fountain grass impact on ground- nesting birds and terrestrial animals as well (California Uni). It is eaten by some animals but not preferred, therefore infestations do not provide an alternative food resource (Johnson; California Uni; Sherif and Siddiqi, 1988; NPCI ). However the prominent seed heads are likely to be a good food source for birds. Therefore significantly modifying, permanently changing or eliminating habitat structure and food resources for animals subsequently affecting faunal populations.

15. Benefits fauna? No information exists in the literature that outlines the benefits this plant has on indigenous fauna. However the prominent seed heads are likely to be a good food source for birds. Dense monospecific stands (Johnson; Tunison, 1992) are likely to provide suitable habitat.

16. Injurious to fauna? No reports on the plant being injurious to fauna (Walsh and Entwisle, 1996; Tunison, 1992).

PEST ANIMAL

17. Food source to pests? The prominent seed heads (Walsh and Entwisle, 1996) are likely to be a good food source for pest birds. However little has been documented on how this plant assists in the success of pest animals.

18. Provides harbor? Dense monospecific stands (Johnson; Tunison, 1992) are likely to provide suitable habitat and coverage for pest species like rabbits. However little has been documented on how this plant assists in the success of pest animals.

AGRICULTURE

19. Impact yield? This species has been noted as an aggressive effect on crops, especially vineyards (Medio ambient Canarias, 1999) overseas. A weed of pasture (Johnson) that is able to form dense monospecific stands … that can exclude all other plants (Johnson; Tunison, 1992). It is not a good pasture species (MISC 2003). The impact has not been quantified, however.

20. Impact quality? Noted as a weed of agriculture, but no impacts on quality were recorded (Johnson; Tunison, 1992; MISC 2003).

21. Affect land values? Unknown.

22. Change land use? Unknown.

23. Increase harvest costs? Unknown.

24. Disease host/vector? Is pest free (Floridata).

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 Bush-it

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referenced by (1)

wra1000: Common Name - F (via fountain grass)

Article: wra6747 (permalink)
Categories: :wra:p, :wra:inv1, :wra:invmh, :wra:inv2, :wra:invml, :wra:inv3, :wra:inv4, :wra:inv5, :wra:invl, :wra:inv6, :wra:invh, :wra:inv7, :wra:inv8, :wra:inv9, :wra:inv10, :wra:inv11, :wra:inv12, :wra:inv13, :wra:invm, :wra:inv14, :wra:inv15, :wra:imp1, :wra:impmh, :wra:imp2, :wra:imp3, :wra:impl, :wra:imp4, :wra:impml, :wra:imp5, :wra:imp6, :wra:imp7, :wra:imp8, :wra:imph, :wra:imp9, :wra:imp10a, :wra:imp10b, :wra:imp10c, :wra:imp11, :wra:imp12, :wra:imp13, :wra:imp14, :wra:imp15, :wra:impm, :wra:imp16, :wra:imp17, :wra:imp18, :wra:imp19, :wra:imp20, :wra:imp21, :wra:imp22, :wra:imp23, :wra:imp24
Date: 9 December 2011; 9:08:43 PM AEDT

Author Name: David Low
Author ID: adminDavid