Australia/New Zealand Weed Risk Assessment adapted for 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. Myrtus communis (myrtle) 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-high) 2 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 2.5 Does the species have a history of repeated introductions outside its natural y range? 3. Naturalized beyond native range n 3.2 Garden/amenity/disturbance weed n 3.3 Weed of agriculture n 3.4 Environmental weed n 3.5 Congeneric weed n 4. Produces spines, thorns or burrs n 4.2 Allelopathic y 4.3 Parasitic n 4.4 Unpalatable to grazing animals 4.5 Toxic to animals n 4.6 Host for recognised pests and pathogens y 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 soils) n 4. Climbing or smothering growth habit n 4.2 Forms dense thickets n 5. Aquatic n -2
5.2 Grass n 5.3 Nitrogen fixing woody plant n 5.4 Geophyte 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 y 6.5 Requires specialist pollinators n 6.6 Reproduction by vegetative fragmentation 6.7 Minimum generative time (years) 4 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 n 7.5 Propagules water dispersed n 7.6 Propagules bird dispersed y 7.7 Propagules dispersed by other animals (externally) y 7.8 Propagules dispersed by other animals (internally) y 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 4 Outcome Evaluate* *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 5 yes total 32 yes Data collected 26-27 Question number Reference Source data. used horticulturally, but no evidence of selection for reduced weediness.2.3 2. 2.2 2.3 2.4 2.5 Dehgan, B. (998) Landscape Plants for used horticulturally 3. no evidence 3.2 no evidence 3.3 no evidence 3.4 no evidence 3.5 no evidence 4. no description of these traits 4.2 Khosh-Khui and Bassiri (979) Inhibition of seedling growth by wild myrtle (Myrtus communis L.). Weed Research 9: 45-49. 4.3 Dehgan, B. (998) Landscape Plants for "Plants of wild myrtle (Myrtus communis L.) collected at full bloom contained substances inhibitory to the germination and seedling growth of perennial ryegrass (Lolium perenne L., cv Hollandi) These results suggest that the possible use of wild myrtle as an evergreen hedge plant needs to be examined further because of possible interference with the growth of nearby lawns and flowers." no description of this 4.4 4.5 no evidence 4.6 4.7 Polizzi (996) Myrtaceae, natural hosts of Cylindrocladium scoparium. Informatore Fitopatologico 46: 59-64. Horticopia 4. Cylindrocladium scoparium "caused serious and widespread defoliation, die-back of shoots and leaf spots on myrtle (Myrtus communis). "This plant is considered mostly allergy free and causes little or no allergy 3
problems in most people." 4.8 no evidence 4.9 Mendes, Gazarini, Rodrigues (2) Acclimation of Myrtus communis to contrasting Mediterranean light environments - effects on structure and chemical composition of foliage and plant water relations. Environmental and Experimental Botany 45: 65-78. 4. Dehgan, B. (998) Landscape Plants for 4. Dehgan, B. (998) Landscape Plants for "Myrtus communis is an evergreen sclerophyll shrub which grows naturally in the Mediterranean area under different conditions of light availability from open clearing (full sunlight) to understory (canopy shading)." fertile, organic soils form: shrub or small tree 4.2 no evidence 5. terrestrial 5.2 Dehgan, B. (998) Landscape Plants for Myrtaceae 5.3 Dehgan, B. (998) Landscape Plants for Myrtaceae 5.4 6. 6.2. Dehgan, B. (998) Landscape Plants for 2. Traveset, Riera, and Mas (2) Ecology of fruit-color polymorphism in Myrtus communis and differential effects of birds and mammals on seed germination and seedling growth. Journal of Ecology 89: 749-76. 6.3 6.4 Mulas and Fadda (24) First observations on biology and organ morphology of myrtle (Myrtus communis L.) flower. Agricoltura Mediterranea 34: 223-235. 6.5 Baydar and Gurel (998) The pollen collection activity and preference of honey bees (Apis mellifera) in the natural habitat of Antalya and some morphological and quality properties of different pollen types. Turkish Journal of Agriculture and Forestry 22: 475-482. 6.6 6.7. Dehgan, B. (998) Landscape Plants for 2. Horticopia 4. 7. 7.2 Dehgan, B. (998) Landscape Plants for. propagate by seed 2. seeds germinable "Controlled pollination tests showed, in all clones, quite a good capability to produce berries both under open and self pollination." pollinated by honey bees in Turkey. slow growth rate 2. average growth rate used horticulturally 4
7.3 no evidence; propagules unlikely to come into contact with produce 7.4 Dehgan, B. (998) Landscape Plants for fruits are berries 7.5 no evidence 7.6 Traveset, Riera, and Mas (2) Ecology of of Ecology 89: 749-76. 7.7 Ciccarelli, Andreucci, Pagni, and Garbari (25) Structure and development of the elaiosome in Myrtus communis L. (Myrtaceae) seeds. Flora 2: 326-33. 7.8 Traveset, Riera, and Mas (2) Ecology of of Ecology 89: 749-76. 8. 8.2. Clemente, Rego, and Correia (24) Patterns of seed survival within fire response groups. Revista de Biologia Lisboa 22: 23-32. 2. Traveset, Riera, and Mas (2) Ecology of of Ecology 89: 749-76. 8.3 8.4 8.5 Birds are the main dispersers of M. communis, and ingestion by birds accelerated germination. seeds of M. communis have elaiosomes for secondary dispersal by ants Fruits of M. communis eaten by small carnivorous mammals (foxes, martens, and weasels) - germination not enhanced by carnivore ingestion like with bird ingestion, but seeds still viable post-dispersal.. One year after burial, 28% of M. communis seeds were viable. BUT 2. seeds are non-dormant 5