Sporobolus indicus (smutgrass)

Transcription

1 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 : Sporobolus indicus (smutgrass) 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) Quality of climate match data (-low; -intermediate; 2-high) 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 natural y range? 3. Naturalized beyond native range y 3.2 Garden/amenity/disturbance weed y 3.3 Weed of agriculture y 3.4 Environmental weed y 3.5 Congeneric weed? 4. Produces spines, thorns or burrs n 4.2 Allelopathic n 4.3 Parasitic n 4.4 Unpalatable to grazing animals y 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 y 4.9 Is a shade tolerant plant at some stage of its life cycle? 4. Grows on infertile soils (oligotrophic, limerock, or excessively draining soils) 4. Climbing or smothering growth habit n 4.2 Forms dense thickets? 5. Aquatic n

2 5.2 Grass y 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 n 6.6 Reproduction by vegetative fragmentation n 6.7 Minimum generative time (years) 7. Propagules likely to be dispersed unintentionally (plants growing in heavily y trafficked areas) 7.2 Propagules dispersed intentionally by people n 7.3 Propagules likely to disperse as a produce contaminant n 7.4 Propagules adapted to wind dispersal y 7.5 Propagules water dispersed y 7.6 Propagules bird dispersed n 7.7 Propagules dispersed by other animals (externally) y 7.8 Propagules dispersed by other animals (internally) n 8. Prolific seed production y? 8.2 Evidence that a persistent propagule bank is formed (> yr) y? 8.3 Well controlled by herbicides y 8.4 Tolerates, or benefits from, mutilation or cultivation Effective natural enemies present in Florida, or east of the continental divide Total Score 8 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:

3 section # questions answered satisfy minimum? A 6 yes B 8 yes C 9 yes total 33 yes Data collected Question number Reference Source data. no evidence of cultivation Parsons and Cuthbertson (2) Noxious Weeds of Parsons and Cuthbertson (2) Noxious Weeds of Wagner, Herbst, and Sohmer (999) Manual of the flowering plants of Hawai'i. University of Hawai'i Press/Bishop Museum Press, Honolulu. Parsons and Cuthbertson (2) Noxious Weeds of. Parsons and Cuthbertson (2) Noxious Weeds of 2. Holm (979) A Geographical Atlas of World Weeds. John Wiley and Sons. 3. Roy, Popay, Champion, James, and Rahman (24) An Illustrated Guide to Common Weeds of New Zealand. 2nd edition. New Zealand Plant Protection Society. "Parramatta grass is particularly aggressive in wet and swampy soils" "A native of South Africa, Parramatta grass has been introduced to North and South America, southern Asia, Indonesia, Hawaii, the South Pacific Islands, New Zealand and Australia." "Native to the Neotropics [but see above], now widely naturalized in tropical regions; in Hawai'i naturalized in disturbed areas" "occurring as a weed in disturbed soils on roadsides and waste places". "often becoming dominant in open sunny situations and seriously reducing pasture production" 2. a common weed of agriculture in Japan, the Philippines, and Trinidad. 3. S. africanus (synonym) is a weed of dry northern pastures in New Zealand. Considered an environmental weed in Australia, New Zealand, and Hawaii. 3.4 Weber (23) Invasive Plant Species of the World. CABI Publishing. 3.5 taxonomy very confused - 3

4 unclear what is synonym and what is congener 4. Parsons and Cuthbertson (2) Noxious Weeds of no description of these traits 4.2 no evidence 4.3 Parsons and Cuthbertson (2) Noxious Weeds of no description of this 4.4. "a tough unpalatable perennial tussock grass" 2. "Mature smutgrass forage is generally unpalatable to. Parsons and Cuthbertson (2) Noxious Weeds of cattle. However, cattle will 2. Mislevy, Shilling, Martin, readily consume the and Hatch (999) Smutgrass (Sporobolus indicus) control regrowth of smutgrass for in bahiagrass (Paspalum notatum) pastures. Weed about 2 to 3 wk following a Technology 3: burn or mowing." 4.5 no evidence no evidence 4.8 "The grass produces large amounts of dead biomass Weber (23) Invasive Plant Species of the World. CABI Publishing. promoting the occurrence of wildfires." 4.9 Parsons and Cuthbertson (2) Noxious Weeds of "often becoming dominant in open sunny situations" USDA, NRCS. 25. The PLANTS Database, Version 3.5 ( Data compiled from various sources by Mark W. Skinner. National Plant Data Center, Baton Rouge, LA USA. growth habit: graminoid 4.2 "Where invasive, the grass Weber (23) Invasive Plant Species of the World. CABI Publishing. forms a dense cover eliminating native vegetation and preventing regeneration of shrubs and trees." [but only up to about m tall] 5. terrestrial 5.2 USDA, NRCS. 25. The PLANTS Database, Version 3.5 ( Data compiled from various sources by Mark W. Skinner. National Plant Data Center, Baton Rouge, LA USA. Poaceae 5.3 USDA, NRCS. 25. The PLANTS Database, Version 3.5 ( Data compiled from various sources by Mark W. Skinner. National Plant Data Center, Baton Rouge, LA USA. herbaceous Poaceae 5.4 Parsons and Cuthbertson (2) Noxious Weeds of roots fibrous Parsons and Cuthbertson (2) Noxious Weeds of "reproducing by seed" likely wind-pollinated (grass) 6.6 Parsons and Cuthbertson (2) Noxious Weeds of "The only means of spread is 4

5 Parsons and Cuthbertson (2) Noxious Weeds of Parsons and Cuthbertson (2) Noxious Weeds of 7.2 no evidence 7.3 no evidence 7.4 Mislevy, Shilling, Martin, and Hatch (999) Smutgrass (Sporobolus indicus) control in bahiagrass (Paspalum notatum) pastures. Weed Technology 3: by seed." "Seeds germinate in spring, the young seedlings developing rapidly and producing flowering stems in mid- to late-summer." "At maturity, seeds become sticky when damp From there they readily attach to animal fur, clothes and machinery. Some seed also spreads in mud sticking to animal hooves, footwear and machinery." seeds are spread by wind 7.5 Mislevy, Shilling, Martin, and Hatch (999) Smutgrass (Sporobolus indicus) control in bahiagrass (Paspalum notatum) pastures. Weed Technology 3: seeds are spread by water 7.6 wind-dispersed grass 7.7 "At maturity, seeds become sticky when damp From there they readily attach to animal fur, clothes and machinery. Some seed also spreads in mud sticking to Parsons and Cuthbertson (2) Noxious Weeds of animal hooves, footwear and machinery." 7.8 wind-dispersed grass Parsons and Cuthbertson (2) Noxious Weeds of 2. Mislevy, Shilling, Martin, and Hatch (999) Smutgrass (Sporobolus indicus) control in bahiagrass (Paspalum notatum) pastures. Weed Technology 3: Weber (23) Invasive Plant Species of the World. CABI Publishing. 2. Mislevy, Shilling, Martin, and Hatch (999) Smutgrass (Sporobolus indicus) control in bahiagrass (Paspalum notatum) pastures. Weed Technology 3: Parsons and Cuthbertson (2) Noxious Weeds of. "it is known to produce immense quantities of seed, for example, an average of 3 seeds per inflorescence and over two million seed heads per hectare has been recorded. Much of the seed, however, appears to be dormant or non-viable." 2. "smutgrass produced in excess of 45, seed per plant, with over,4 seed per panicle". "A large seed bank accumulates in the soil." 2. "Smutgrass seeds remain viable for 2 or more yr" [unclear whether in soil or not] "Spraying with flupropanate before seed heads appear gives good selective 5

6 control Non-selective control can be obtained with 2,2-DPA, amitrole + 2,2-DPA mixtures, amitrole + atrazine mixtures or with fluazifop." 6