Himalayan balsam (Impatiens glandulifera)

Present distribution

Scientific name:	Impatiens glandulifera (Royle).
Common name(s):	Himalayan balsam

This weed is not known to be naturalised in Victoria

Habitat:

It grows in forest up to the timber line, as well as more open and disturbed habitats, relative frost tolerance (Tabak & von Wettberg 2008). Moist
localities, river valleys (Cigic 2003). Tolerates a wide variety of soil types, favours shaded and nutrient rich (SWIS 2009).

Potential distribution

Potential distribution produced from CLIMATE modelling refined by applying suitable landuse and vegetation type overlays with CMA boundaries

Map Overlays Used

Land Use:
Forestry; pasture irrigation

Ecological Vegetation Divisions
Freshwater wetland (permanent); treed swampy wetland; lowland forest; forby forest; damp forest; riparian; wet forest; rainforest; high altitude shrubland/woodland; high altitude wetland; granitic hillslopes; western plains woodland; riverine woodland/forest; freshwater wetland (ephemeral)

Colours indicate possibility of Impatiens glandulifera infesting these areas.

In the non-coloured areas the plant is unlikely to establish as the climate, soil or landuse is not presently suitable.

Red= Very high	Orange = Medium
Yellow = High	Green = Likely

Impact

QUESTION	COMMENTS	RATING	CONFIDENCE
Social
1. Restrict human access?	“Plant usually grows in large populations and it can be up to 2 – 3 m tall. Suitable locations for this plant are creek and river banks” (Cigic 2003). “Often forms dense even aged stands (Hulme & Bremner 2006). Major impediment (TCWM 2009) Major impediment to access waterways or machinery. Significant works required to provide reasonable access, tracks closed or impassable	H	MH
2. Reduce tourism?	As large monospecific stands can form, 2-3 m tall along rivers and creeks, boating, fishing, general enjoyment of these areas can be severely reduced. Some recreational uses affected.	MH	MH
3. Injurious to people?	No spines, burrs, thorns but probably contains calcium oxalate as in I. capensis which is harmful raw (GB 2009). Toxic properties at most times in the year.	MH	M
4. Damage to cultural sites?	Roots are not very strong (Tabak & Wettburg 2008; SWIS 2009). Unlikely to structural damage. Moderate visual effect.	ML	MH
Abiotic
5. Impact flow?	“Plant usually grows in large populations and it can be up to 2 – 3 m tall. Suitable locations for this plant are creek and river banks” (Cigic 2003). As it is an annual (FNZS 2009) die back of large, tall monospecific stands could fall in water and reduce flow, or while alive leaves and branches could hang in the water and reduce flow.	M	MH
6. Impact water quality?	“Plant usually grows in large populations and it can be up to 2 – 3 m tall. Suitable locations for this plant are creek and river banks” (Cigic 2003).Light levels would be reduced. Noticeable but minor effects in either dissolved O2 or light levels.	ML	M
7. Increase soil erosion?	“Grows most commonly in gullies and streams …..In favourable conditions it grows very tall and may put out prop roots for anchorage (FNZS 2009). “been shown to compete with native vegetation and possibly lead to greater erosion of riverbanks when it replaces perennial vegetation in Europe (Tabak & Wettberg 2008). High probability of large scale soil movement with minor off-site implications.	MH	MH
8. Reduce biomass?	“Plant usually grows in large populations and it can be up to 2 – 3 m tall” (Cigic 2003). “Often forms dense even aged stands (Hulme & Bremner 2006). Biomass may increase.	L	MH
9. Change fire regime?	No information on I. glandulifera and fire regime. The large biomass of tall even aged dense stands (Cigic 2003) and the plant being annual (FNZS 2009) means a simulataneous die back would add plenty of fuel for a fire.	M	M
Community Habitat
10. Impact on composition (a) high value EVC	EVC = Valley grassy forest (V); CMA = East Gippsland; Bioregion = Highlands Southern Fall; H CLIMATE potential. “Populations of this plant take up a significant area of moist localities, especially in river valleys” (Cigic 2003). Tolerates a wide variety of soil types, favours shaded and nutrient rich (SWIS 2009). Major displacement of some dominant or indicator spp. within any one strata/layer (eg. Ground cover, forbs, shrubs & trees).	MH	MH
(b) medium value EVC	EVC = Riverine Escarpment Scrub (R); CMA =East Gippsland; Bioregion = Highlands Southern Fall; H CLIMATE potential. It grows in forest up to the timber line, as well as more open and disturbed habitats, relative frost tolerance (Tabak & von Wettberg 2008).“Populations of this plant take up a significant area of moist localities, especially in river valleys” (Cigic 2003). Major displacement of some dominant or indicator spp. within any one strata/layer (eg. Ground cover, forbs, shrubs & trees).	MH	MH
(c) low value EVC	EVC = Riparian Forest (LC); CMA =West Gippsland; Bioregion = Highlands Southern Fall; H CLIMATE potential. It grows in forest up to the timber line, as well as more open and disturbed habitats, relative frost tolerance (Tabak & von Wettberg 2008). “Populations of this plant take up a significant area of moist localities, especially in river valleys” (Cigic 2003). Major displacement of some dominant or indicator spp. within any one strata/layer (eg. Ground cover, forbs, shrubs & trees).	MH	MH
11. Impact on structure?	“In Austria populations of this plant take up a significant area of moist localities, especially in river valleys…. And are considered dangerous for survival of forest seedlings” (Cigic 2003). Considered to be one of the most invasive riparian weeds (Tabak & Wettberg 2008). “Considered to be a serious weed of riparian zones, wetlands, woodlands, and waste grounds…… been shown to compete with native vegetation (Tabak & Wettberg 2008). Extensive stands may reduce species richness by as much as 25% (Hulme & Bremner 2006). Minor effect on >60% of the layers or major effect on < 60% of the floral strata.	MH	MH
12. Effect on threatened flora?	“Been shown to compete with native vegetation” (Tabak & Wettberg 2008). The rich and abundant nectar produced by its flowers attracts pollinators at the expense of the pollination of co-occuring species (Tabak & Wettberg 2008). Outcompetes native species especially in the riparian zone (SWIS 2009).	M	MH
Fauna
13. Effect on threatened fauna?	Causes local change in cover and/or dominance of native species (Hulme & Bremner 2006). Extensive stands may reduce species richness by as much as 25% (Hulme & Bremner 2006). Likely to reduce food and habitat availability for a threatened species. Probably contains calcium oxalate as in I. capensis which is harmful raw (GB 2009). Likely to be toxic to fauna.	M	M
14. Effect on non-threatened fauna?	Causes local change in cover and/or dominance of native species (Hulme & Bremner 2006). Extensive stands may reduce species richness by as much as 25% (Hulme & Bremner 2006).Likely to reduce food and habitat availability for non-threatened fauna species. Probably contains calcium oxalate as in I. capensis which is harmful raw (GB 2009). Likely to be toxic to fauna. Reduction in habitat for fauna spp., leading to reduction in numbers of individuals, but NOT to local extinction.	MH	MH
15. Benefits fauna?	The rich and abundant nectar produced by its flowers attracts pollinators at the expense of the pollination of cooccurring species (Tabak & Wettberg 2008). Provides some assistance in either food or shelter to desirable species.	MH	MH
16. Injurious to fauna?	Probably contains calcium oxalate as in I. capensis which is harmful raw (GB 2009). Likely to be toxic to fauna.	M	M
Pest Animal
17. Food source to pests?	As the vegetative parts are likely to contain toxins (GB 2009) it would not provide food to pests. But as it provides abundant nectar (Tabak & Wettberg 2008) some pests may benefit from this food supply such as insect pests. Supplies food for one or more minor pest species. (eg. Blackbirds or environmental insect pests).	ML	MH
18. Provides harbour?	“Plant usually grows in large populations and it can be up to 2 – 3 m tall” (Cigic 2003). “Often forms dense even aged stands (Hulme & Bremner 2006). No spines or burrs (SWIS 2009) so likely to provide harbour for pests such as foxes or bush rabbits. Capacity to harbour rabbits or foxes at low densities or as overnight cover.	MH	MH
Agriculture
19. Impact yield?	“In Austria populations of this plant take up a significant area of moist localities, especially in river valleys, those kinds of localities are suitable for forestation, so the species I. glandulifera is considered dangerous for survival of forest seedlings” (Cigic 2003).	M	MH
20. Impact quality?	“often on grazing ground” (GB 2009). As can form extensive monocultures (Cigic 2009) and probably contains toxins (GB 2009) is likely to reduce food availability, and forms thick extensive stands along river banks (Cigic 2009) – likely to restrict access to water for livestock.	M	MH
21. Affect land value?	No information on how it may affect land value. Control is difficult (SWIS 2009; Weber 2003). Considered to be one of the most invasive riparian weeds (Tabak & Wettberg 2008).	MH	ML
22. Change land use?	No information on changing land use.	M	L
23. Increase harvest costs?	Control is difficult (SWIS 2009; Weber 2003). Considered to be one of the most invasive riparian weeds (Tabak & Wettberg 2008). Not listed a crop weed but may increase costs when control in grazing land is required.	M	ML
24. Disease host/vector?	No information on disease host/vector.	M	L

Invasive

QUESTION	COMMENTS	RATING	CONFIDENCE
Establishment
1. Germination requirements?	Seed germinate almost synchronously is early spring after winter’s cold temperatures break their physiological dormancy (Tabak & Wettberg 2008). Requires natural seasonal disturbances such as seasonal rainfall, spring/summer temperatures for germination.	MH	MH
2. Establishment requirements?	It grows in forests up to the timberline, as well as more open and disturbed habitats (Tabak & Wettberg 2008). Can establish under moderate canopy/litter cover	MH	MH
3. How much disturbance is required?	Distribution and spread is determined by anthropogenic influence (Cigic 2003). Establishes in relatively intact or only minor disturbed natural ecosystems (eg. wetlands, riparian, riverine, grasslands, open woodlands); in vigorously growing crops or in well-established pastures.	MH	MH
Growth/Competitive
4. Life form?	A large glabrous annual (Weber 2003) other	L	H
5. Allelopathic properties?	None reported (Rice 1984).	M	L
6. Tolerates herb pressure?	“plants damaged early in the season are able to resprout and still produce new seeds” (Weber 2003). Consumed but non-preferred or consumed but recovers quickly; capable of flowering /seed production under moderate herbivory pressure (where moderate = normal; not overstocking or heavy grazing).	MH	MH
7. Normal growth rate?	“High vegetative growth rate” (Tabak & Wettberg 2008). Large and fast growing herb (Weber 2003). Rapid growth rate that will exceed most other species of the same life form.	H	MH
8. Stress tolerance to frost, drought, w/logg, sal. etc?	“Relative frost tolerance” (Tabak & Wettberg 2008). Populations of this plant take up a significant area of moist localities, especially in river valleys” (Cigic 2003). Tolerant to at least two and susceptible to at least one.	ML	MH
Reproduction
9. Reproductive system	The rich and abundant nectar produced by its flowers attracts pollinators at the expense of the pollination of cooccurring species (Tabak & Wettberg 2008). Hybridizes (SWIS 2009). Self seeds (GB 2009). Sexual (Self and cross pollination).	ML	MH
10. Number of propagules produced?	A dense population can produce up to 30 000 seeds per meter square, but the plant does not have a persistent seed bank (Weber 2003). A single plant can produce up to 10 000 seeds (SWIS 2009). Above 2000.	H	MH
11. Propagule longevity?	Plant does not have a persistent seed bank (Weber 2003). Seeds can survive 2 years (SWIS 2009).	L	MH
12. Reproductive period?	Forms persistent populations (Tabak & Wetberg 2008). Species forms self sustaining monoculture.	H	MH
13. Time to reproductive maturity?	Annual (FNZS 2009) Produces propagules 1-2 years after germination.	MH	H
Dispersal
14. Number of mechanisms?	“Dispersal from established from established from established populations by both natural and human-aided means (such as seed collecting, or picking flowering stems for bouquets and discarding them outside while having viable seeds’ (Tabak & Wettberg 2008). “The seeds of I. glandulifera can float for up to 40 days and remain viable” (Tabak & Wettberg 2008). Propagules spread by wind, water, attachment or accidental human dispersal.	MH	MH
15. How far do they disperse?	Findings of this species in Croatia indicate that it is disseminated in two ways: by water streams and spreading from village gardens (Cigic 2003). Very likely that at least one propagule will disperse greater than one kilometre.	H	MH

References

Cigić, P. Nikolić, T.. Plazibat, M. Hršak, V. & Jelaska S. D. (2003) The distribution of the genus Impatiens L. (Balsaminaceae) in Medvednica Nature Park, Croatia (Izvorni znanstveni članak) Natura Croatica, Vol. 12 No. 1, 2003

FNZS (2009) Flora of New Zealand Series. http://floraseries.landcareresearch.co.nz/pages/Taxon.aspx?id=_a28e2262-987c-4e58-a8d2-5024f35f2f72&fileName=Flora%204.xml (03/2009).

GB (2009) Garden Bed. Information obtained from Plants for a future. http://gardenbed.com/I/1919.asp (04/2009).

Hulme, P. E. & Bremner, E. T. (2006) Assessing the impact of Impatiens glandulifera on riparian habitats: partitioning diversity components following species removal. Journal of applied ecology 43, 43-50.

Rice, E. L. (1984) Allelopathy. Academic press.

SWIS (2009) Invasive alien species in Switzerland: Factsheets. Swiss confederation. Federal office for the environment FOEN
www.bafu.admin.ch/publikationen/publikation/00028/index.html?lang=en&downloadshop=NHzLpZig7t...s-.pdf

Tabak, N M.; von Wettberg, E 2008 Native and Introduced Jewelweeds of the Northeast. Northeastern Naturalist, Vol. 15, no. 2, pp. 159-176, Jun 2008.

TCWM (2009). Tailored Conservation and weed management. Impatiens glandulifera. http://t-c-m.co.uk/cms_misc/images/default/IMPATIENS (03/09).

Weber, E (2003) Invasive plant species of the world. CABI publishing.

Global present distribution data references

Australian National Herbarium (ANH) (2008) Australia’s Virtual Herbarium, Australian National Herbarium, Centre for Plant Diversity and Research, Available at
http://www.anbg.gov.au/avh/ (verified 17/02/2009).

Department of the Environment and Heritage (Commonwealth of Australia). (1993 – On-going) Australian Plant Name Index (APNI) http://www.cpbr.gov.au/apni/index.html (verified 07/05/2009).

Global Biodiversity Information Facility (GBIF) (2008) Global biodiversity information facility, Available at http://www.gbif.org/ (verified 17/02/2009).

Integrated Taxonomic Information System. (2009) Available at http://www.itis.gov/ (verified 07/05/2009).

Missouri Botanical Gardens (MBG) (2009) w3TROPICOS, Missouri Botanical Gardens Database, Available at http://mobot.mobot.org/W3T/Search/vast.html (viewed 17/02/2009).

United States Department of Agriculture. Agricultural Research Service, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN) [Online Database]. Taxonomy Query. (2009) Available at http://www.ars-grin.gov/cgi-bin/npgs/html/taxgenform.pl (verified 26/03/2009).

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