TAXON: Polygala myrtifolia L. SCORE: 11.0 RATING: High Risk Taxon: Polygala myrtifolia L. Family: Polygalaceae Common Name(s): butterfly bush Synonym(s): Polygala pinifolia Poir. myrtle leaf milkwort Psychanthus myrtifolius (L.) Raf. parrotbush Psychanthus myrtifolius (L.) Spach September bush Assessor: Chuck Chimera Status: Assessor Approved End Date: 15 May 2017 WRA Score: 11.0 Designation: H(HPWRA) Rating: High Risk Keywords: Perennial Shrub, Environmental Weed, Ornamental, Dense Stands, Ant-Dispersed Qsn # Question Answer Option Answer 101 Is the species highly domesticated? y=-3, n=0 n 102 Has the species become naturalized where grown? 103 Does the species have weedy races? Species suited to tropical or subtropical climate(s) - If 201 island is primarily wet habitat, then substitute "wet (0-low; 1-intermediate; 2-high) (See Appendix 2) Intermediate tropical" for "tropical or subtropical" 202 Quality of climate match data (0-low; 1-intermediate; 2-high) (See Appendix 2) High 203 Broad climate suitability (environmental versatility) y=1, n=0 n Native or naturalized in regions with tropical or 204 y=1, n=0 n subtropical climates Does the species have a history of repeated introductions 205 y=-2, ?=-1, n=0 y outside its natural range? 301 Naturalized beyond native range y = 1*multiplier (see Appendix 2), n= question 205 y 302 Garden/amenity/disturbance weed n=0, y = 1*multiplier (see Appendix 2) n 303 Agricultural/forestry/horticultural weed n=0, y = 2*multiplier (see Appendix 2) n 304 Environmental weed n=0, y = 2*multiplier (see Appendix 2) y 305 Congeneric weed n=0, y = 1*multiplier (see Appendix 2) y 401 Produces spines, thorns or burrs y=1, n=0 n 402 Allelopathic 403 Parasitic y=1, n=0 n 404 Unpalatable to grazing animals 405 Toxic to animals y=1, n=0 n 406 Host for recognized pests and pathogens y=1, n=0 y 407 Causes allergies or is otherwise toxic to humans y=1, n=0 n 408 Creates a fire hazard in natural ecosystems Creation Date: 15 May 2017 (Polygala myrtifolia L.) Page 1 of 18 TAXON: Polygala myrtifolia L. SCORE: 11.0 RATING: High Risk Qsn # Question Answer Option Answer 409 Is a shade tolerant plant at some stage of its life cycle Tolerates a wide range of soil conditions (or limestone 410 y=1, n=0 y conditions if not a volcanic island) 411 Climbing or smothering growth habit y=1, n=0 n 412 Forms dense thickets y=1, n=0 y 501 Aquatic y=5, n=0 n 502 Grass y=1, n=0 n 503 Nitrogen fixing woody plant y=1, n=0 n Geophyte (herbaceous with underground storage organs 504 y=1, n=0 n -- bulbs, corms, or tubers) Evidence of substantial reproductive failure in native 601 y=1, n=0 n habitat 602 Produces viable seed y=1, n=-1 y 603 Hybridizes naturally 604 Self-compatible or apomictic y=1, n=-1 y 605 Requires specialist pollinators y=-1, n=0 n 606 Reproduction by vegetative fragmentation y=1, n=-1 n 607 Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1 3 Propagules likely to be dispersed unintentionally (plants 701 y=1, n=-1 y growing in heavily trafficked areas) 702 Propagules dispersed intentionally by people y=1, n=-1 y 703 Propagules likely to disperse as a produce contaminant y=1, n=-1 n 704 Propagules adapted to wind dispersal y=1, n=-1 y 705 Propagules water dispersed y=1, n=-1 y 706 Propagules bird dispersed 707 Propagules dispersed by other animals (externally) y=1, n=-1 y 708 Propagules survive passage through the gut 801 Prolific seed production (>1000/m2) y=1, n=-1 n Evidence that a persistent propagule bank is formed (>1 802 yr) 803 Well controlled by herbicides y=-1, n=1 y 804 Tolerates, or benefits from, mutilation, cultivation, or fire y=1, n=-1 y Effective natural enemies present locally (e.g. introduced 805 biocontrol agents) Creation Date: 15 May 2017 (Polygala myrtifolia L.) Page 2 of 18 TAXON: Polygala myrtifolia L. SCORE: 11.0 RATING: High Risk Supporting Data: Qsn # Question Answer 101 Is the species highly domesticated? n Source(s) Notes [Not domesticated] "As mentioned, there are different forms of Polygala myrtifolia. At Kirstenbosch we have selected a beautiful, Van der Walt, L. 2003. Polygala myrtifolia L. PlantZAfrica. white-flowering form called P. myrtifolia 'White Feathers'. When in SANBI. full flower from August to October the whole bush is covered with https://www.plantzafrica.com/plantnop/polygalamyrt.ht white flowers, a spectacular show. The leaves of the white form are m. [Accessed 15 May 2017] slightly greyer and are lovely when contrasted with other leaves, forms and colours." 102 Has the species become naturalized where grown? Source(s) Notes WRA Specialist. 2017. Personal Communication NA 103 Does the species have weedy races? Source(s) Notes WRA Specialist. 2017. Personal Communication NA Species suited to tropical or subtropical climate(s) - If 201 island is primarily wet habitat, then substitute "wet Intermediate tropical" for "tropical or subtropical" Source(s) Notes "Native: USDA, ARS, Germplasm Resources Information Network. Africa 2017. National Plant Germplasm System [Online Southern Africa: South Africa - Cape Province, - KwaZulu-Natal, - Database]. http://www.ars-grin.gov/npgs/index.html. Free State" [Accessed 12 May 2017] "Neither this species nor the related purple broom can withstand Sheat, B. & Schofield, G. 1995. Complete Gardening in heavy frost, and are best suited to the temperate parts of the Southern Africa. Struik Publishers, Cape Town, South country. However, they will grow, but less satisfactorily, in Africa subtropical areas." 202 Quality of climate match data High Source(s) Notes USDA, ARS, Germplasm Resources Information Network. 2017. National Plant Germplasm System [Online Database]. http://www.ars-grin.gov/npgs/index.html. [Accessed ] 203 Broad climate suitability (environmental versatility) n Source(s) Notes Creation Date: 15 May 2017 (Polygala myrtifolia L.) Page 3 of 18 TAXON: Polygala myrtifolia L. SCORE: 11.0 RATING: High Risk Qsn # Question Answer [Generally restricted to areas with cool temperate, semi-arid or Mediterranean-type climate] "No quantitative data are available on the climatic requirements of P. myrtifolia. In its native and introduced range, P. myrtifolia has a broad ecological tolerance, but Adair, R. J., Shackleton, A., Stajsic, V., & Gajaweera, R. is generally restricted to areas with cool temperate, semi-arid or (2012). The biology of Australian weeds 61. Polygala Mediterranean-type climate. The species has a large altitudinal myrtifolia L. Plant Protection Quarterly, 27(4), 119-130 range in South Africa, where it occurs from sea level to 1350 m (Bredenkamp 2003) (Figure 3). The broad-leaf form of P. myrtifolia (P. myrtifolia var. grandiflora) naturally occurs most abundantly in humid temperate areas of South Africa. In coastal regions, where P. myrtifolia is most abundant, frosts are uncommon or rarely severe." Native or naturalized in regions with tropical or 204 n subtropical climates Source(s) Notes "Naturalized: Australasia USDA, ARS, Germplasm Resources Information Network. Australia: Australia 2017. National Plant Germplasm System [Online New Zealand: New Zealand Database]. http://www.ars-grin.gov/npgs/index.html. Europe [Accessed 13 May 2017] : Europe" "Neither this species nor the related purple broom can withstand Sheat, B. & Schofield, G. 1995. Complete Gardening in heavy frost, and are best suited to the temperate parts of the Southern Africa. Struik Publishers, Cape Town, South country. However, they will grow, but less satisfactorily, in Africa subtropical areas." Does the species have a history of repeated 205 y introductions outside its natural range? Source(s) Notes "Polygala myrtifolia is a popular garden ornamental in South Africa, Adair, R. J., Shackleton, A., Stajsic, V., & Gajaweera, R. and is also widely utilized for horticultural purposes in other (2012). The biology of Australian weeds 61. Polygala temperate climates, particularly Australia, New Zealand, in the myrtifolia L. Plant Protection Quarterly, 27(4), 119-130 United States of America and southern Europe (Esler 1988, Cervelli 2001, Meerow and Ayala-Silva 2005)." 301 Naturalized beyond native range y Source(s) Notes "As P. myrtifolia has attractive purple and white flowers which are present throughout the year, it is highly likely the species was Adair, R. J., & Neser, S. (1996). The potential for biological introduced as a garden ornamental. It has subsequently become control of the South African weed Polygala myrtifolia. In naturalized in native vegetation in coastal areas of Victoria, New Proceedings of the 11th Australian Weeds Conference, ed. South Wales, Tasmania, South Australia and Western Australia RCH Shepherd (pp. 438-9) (Carter et al. 1990). In Victoria and South Australia, large infestations occur on calcareous soils with a history of land disturbance. Minor infestations occur in the other states." Creation Date: 15 May 2017 (Polygala myrtifolia L.) Page 4 of 18 TAXON: Polygala myrtifolia L. SCORE: 11.0 RATING: High Risk Qsn # Question Answer "In Australia, P. myrtifolia is naturalized in five States (APC2011), with infraspecific taxa recognized only in Victoria (Walsh and Entwisle 1999, APC 2011). Naturalized populations of P. myrtifolia in Adair, R. J., Shackleton, A., Stajsic, V., & Gajaweera, R. Australia closely match the morphological characters of P. myrtifolia (2012). The biology of Australian weeds 61. Polygala var. myrtifolia found in coastal and hilly situations on the Cape myrtifolia L. Plant Protection Quarterly, 27(4), 119-130 Peninsula (R. Adair unpublished observations). There is a second entity, a horticultural variant, Polygala ͚Grandiflora͕͛which is common in Australi"an horticulture, but as far as we know is not naturalized. "N.: common from Auckland City northwards, also established in Webb, C. J., Sykes, W. R., & Garnock-Jones, P. J. 1988.