Australia/New Zealand Weed Risk Assessment adapted for Florida. Data used for analysis published in: Gordon, D.R., D.A. Onderdonk, A.M. Fox, R.K. Stocker, and C. Gantz. 28. Predicting Invasive Plants in Florida using the Australian Weed Risk Assessment. Invasive Plant Science and Management : 78-95. Ruellia tweediana (Mexican petunia) Question number Question Answer Score. Is the species highly domesticated? n.2 Has the species become naturalised where grown?.3 Does the species have weedy races? 2. Species suited to Florida's USDA climate zones (-low; -intermediate; 2-2 high) 2.2 Quality of climate match data (-low; -intermediate; 2-high) 2 2.3 Broad climate suitability (environmental versatility) 2.4 Native or naturalized in habitats with periodic inundation y 2.5 Does the species have a history of repeated introductions outside its y natural range? 3. Naturalized beyond native range y 3.2 Garden/amenity/disturbance weed? 3.3 Weed of agriculture y 3.4 Environmental weed n 3.5 Congeneric weed y 4. Produces spines, thorns or burrs n 4.2 Allelopathic n 4.3 Parasitic n 4.4 Unpalatable to grazing animals 4.5 Toxic to animals n 4.6 Host for recognised pests and pathogens 4.7 Causes allergies or is otherwise toxic to humans n 4.8 Creates a fire hazard in natural ecosystems n 4.9 Is a shade tolerant plant at some stage of its life cycle y 4. Grows on infertile soils (oligotrophic, limerock, or excessively draining y soils) 4. Climbing or smothering growth habit n 4.2 Forms dense thickets n
5. Aquatic n 5.2 Grass n 5.3 Nitrogen fixing woody plant n 5.4 Geophyte n 6. Evidence of substantial reproductive failure in native habitat 6.2 Produces viable seed y 6.3 Hybridizes naturally 6.4 Self-compatible or apomictic 6.5 Requires specialist pollinators 6.6 Reproduction by vegetative fragmentation 6.7 Minimum generative time (years) 7. Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas) 7.2 Propagules dispersed intentionally by people y 7.3 Propagules likely to disperse as a produce contaminant n 7.4 Propagules adapted to wind dispersal y 7.5 Propagules water dispersed n 7.6 Propagules bird dispersed n 7.7 Propagules dispersed by other animals (externally) n 7.8 Propagules dispersed by other animals (internally) n 8. Prolific seed production 8.2 Evidence that a persistent propagule bank is formed (> yr) y? 8.3 Well controlled by herbicides? - - - - - 8.4 Tolerates, or benefits from, mutilation or cultivation 8.5 Effective natural enemies present in Florida, or east of the continental divide Total Score Outcome Reject* *Used secondary screen from: Daehler, C. C., J.L. Denslow, S. Ansari, and H. Kuo. 24. A risk assessment system for screening out harmful invasive pest plants from Hawaii s and other Pacific islands. Conserv. Biol. 8: 36-368. 2
section # questions answered satisfy minimum? A 6 yes B yes C 4 yes total 3 yes Data collected 26-27 Question number Reference Source data. some cultivars are likely as S. Wilson, pers. comm. weedy as the wildtype form.2.3 2. 2.2 2.3 2.4 "These plants also do very Horticopia 4. well in swamps and areas that stay too wet for even grass to grow." 2.5. Wagner, Herbst, and Sohmer (999) Manual of the 2. Wilson and Mecca (23) Seed production and germination of eight cultivars and the wild type of Ruellia tweediana: a potentially invasive ornamental. Journal of Environmental Horticulture 2: 37-43. 3. 3.2 Wagner, Herbst, and Sohmer (999) Manual of the Liogier (997) Descriptive Flora of Puerto Rico and Adjacent Islands. Vol. 5. Editorial de la Universidad de Puerto Rico. 3.3 Holm (979) A Geographical Atlas of World Weeds. John Wiley and Sons. Native to Mexico; also present in Hawaii () and the Virgin Islands and Puerto Rico (2). Used horticulturally (2). "Native to Mexico; in Hawaii cultivated as an ornamental but easily escaping, now naturalized and often found in dry habitats such as cracks in sidewalks and disturbed, shaded gulch bottoms" "Common as a weed in P.R." [but counted as an agricultural weed in Puerto Rico (see 3.3) - not counting here as well, since it's not clear what type of weed is meant] Considered a common weed of agriculture in Puerto Rico. 3.4 no evidence 3.5. Waterhouse (997) The major invertebrate pests and. R. prostrata is a weed of weeds of agriculture and plantation forestry in the southern and western Pacific. ACIAR Monograph No. 44, roadsides and tree crops in 99p. 2. Holm (979) A Geographical Atlas of World the Pacific. 2. R. tuberosa Weeds. John Wiley and Sons. considered a serious weed of 3
agriculture in Thailand. 4. Wagner, Herbst, and Sohmer (999) Manual of the no description of these traits 4.2 no evidence 4.3 Wagner, Herbst, and Sohmer (999) Manual of the no description of this 4.4 4.5 no evidence 4.6 4.7 no evidence 4.8 no evidence 4.9 exposure: full shade to partial Horticopia 4. sun 4. "Suitable soil is welldrained/loamy, Horticopia 4. sandy or clay." 4. USDA, NRCS. 25. The PLANTS Database, Version 3.5 Baton Rouge, LA 7874-449 USA. growth habit: subshrub, shrub, forb/herb 4.2 no evidence 5. terrestrial 5.2 USDA, NRCS. 25. The PLANTS Database, Version 3.5 Baton Rouge, LA 7874-449 USA. Acanthaceae 5.3 USDA, NRCS. 25. The PLANTS Database, Version 3.5 Baton Rouge, LA 7874-449 USA. Acanthaceae 5.4 "This plant's roots Horticopia 4. are...fibrous." 6. 6.2. Horticopia 4. 2. Wilson and Mecca (23) Seed production and germination of eight cultivars and the wild type of Ruellia tweediana: a potentially invasive ornamental. Journal of Environmental Horticulture 2: 37-43. 6.3 6.4 6.5 6.6 6.7 Wilson and Mecca (23) Seed production and germination of eight cultivars and the wild type of Ruellia Environmental Horticulture 2: 37-43.. propagation from seeds; "Plants seeds themselves into the garden and can form clumps many feet across. Seedlings can also be found many feet away from original plants." 2. Seven of eight cultivars, and wild type, all produced viable seed. Several cultivars and wild type of R. tweediana flowered approx. 3 months after germination. 7. 7.2 Wilson and Mecca (23) Seed production and R. tweediana is extensively 4
germination of eight cultivars and the wild type of Ruellia Environmental Horticulture 2: 37-43. 7.3 no evidence 7.4 Witztum and Schulgasser (995) The mechanics of seed expulsion in Acanthaceae. Journal of Theoretical Biology 76: 53-542. cultivated for its ornamental value. Ruellia brittoniana [synonym] has explosive dispersal of its seeds. "The 6-2 disk shaped, slightly oblong seeds are thrown out to distances of up to 2.5-3 m." 7.5 no evidence 7.6 wind dispersed 7.7 Wagner, Herbst, and Sohmer (999) Manual of the fruit is an ellipsoid capsule, 2-2.5 cm long, smooth externally 7.8 wind dispersed 8. Witztum and Schulgasser (995) The mechanics of seed expulsion in Acanthaceae. Journal of Theoretical Biology 76: 53-542. 6-2 seeds per fruit 8.2 8.3 8.4 8.5. Hammer (22) Mexican bluebell (Ruellia tweediana Griseb.): a pretty invasive weed. Wildland Weeds 5: 6-8. 2. Wilson and Mecca (23) Seed production and germination of eight cultivars and the wild type of Ruellia Environmental Horticulture 2: 37-43.. "Attempts to eradicate the species by hand removal is [sic] nearly futile because a persistent seed bank in the soil allows it to reappear long after eradication efforts are thought to be successful." 2. Germination of seeds stored for 2 months varied between 23 and %, depending on type and temperature. [stored in laboratory, not in soil] 5