Imperata cylindrica (L.) Beauv. Family - Poaceae. Common Names - alang-alang, blady grass, cogon grass, imperata, Japanese blood grass, satintail.

Answer

Score

1.01

Is the species highly domesticated? (If answer is 'no' then go to question 2.01)

n

0

1.02

Has the species become naturalized where grown?

1.03

Does the species have weedy races?

2.01

Species suited to tropical or subtropical climate(s) (0-low; 1-intermediate; 2-high) – If island is primarily wet habitat, then substitute “wet tropical” for “tropical or subtropical”

2

2.02

Quality of climate match data (0-low; 1-intermediate; 2-high) see appendix 2

2

2.03

Broad climate suitability (environmental versatility)

y

1

2.04

Native or naturalized in regions with tropical or subtropical climates

y

1

2.05

Does the species have a history of repeated introductions outside its natural range? y=-2

y

3.01

Naturalized beyond native range y = 1*multiplier (see Append 2), n= question 2.05

y

2

3.02

Garden/amenity/disturbance weed y = 1*multiplier (see Append 2)

3.03

Agricultural/forestry/horticultural weed y = 2*multiplier (see Append 2)

y

4

3.04

Environmental weed y = 2*multiplier (see Append 2)

y

4

3.05

Congeneric weed y = 1*multiplier (see Append 2)

4.01

Produces spines, thorns or burrs

n

0

4.02

Allelopathic

4.03

Parasitic

y

1

4.04

Unpalatable to grazing animals

y

1

4.05

Toxic to animals

n

0

4.06

Host for recognized pests and pathogens

4.07

Causes allergies or is otherwise toxic to humans

4.08

Creates a fire hazard in natural ecosystems

y

1

4.09

Is a shade tolerant plant at some stage of its life cycle

y

1

4.1

Tolerates a wide range of soil conditions (or limestone conditions if not a volcanic island)

y

1

4.11

Climbing or smothering growth habit

n

0

4.12

Forms dense thickets

y

1

5.01

Aquatic

n

0

5.02

Grass

y

1

5.03

Nitrogen fixing woody plant

n

0

5.04

Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers)

n

0

6.01

Evidence of substantial reproductive failure in native habitat

n

0

6.02

Produces viable seed.

y

1

6.03

Hybridizes naturally

y

1

6.04

Self-compatible or apomictic

n

-1

6.05

Requires specialist pollinators

n

0

6.06

Reproduction by vegetative fragmentation

y

1

6.07

Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1

7.01

Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas)

y

1

7.02

Propagules dispersed intentionally by people

y

1

7.03

Propagules likely to disperse as a produce contaminant

y

1

7.04

Propagules adapted to wind dispersal

y

1

7.05

Propagules water dispersed

n

-1

7.06

Propagules bird dispersed

n

-1

7.07

Propagules dispersed by other animals (externally)

7.08

Propagules survive passage through the gut

n

-1

8.01

Prolific seed production (>1000/m2)

y

1

8.02

Evidence that a persistent propagule bank is formed (>1 yr)

n

-1

8.03

Well controlled by herbicides

y

-1

8.04

Tolerates, or benefits from, mutilation, cultivation, or fire

y

1

8.05

Effective natural enemies present locally (e.g. introduced biocontrol agents)

Total score:

22

Notes

Reference

1.01

No evidence.

1.02

1.03

2.01

(1) Native range: A native to southeast Asia, I. cylindrica is found throughout the temperate and tropic zones. The exact center of origin of I. cylindrica is in doubt, but is believed to be East Africa (Evans 1987 1991, in Van Loan Meeker and Minno 2002). It is found mainly in tropical and subtropical areas with 75 to 500 cm of annual rainfall. It has been found at latitiudes from 45°N (Japan) to 45°S (New Zealand), and from sea level to over 2,000 m elevation

(1) http://www.issg.org/database/species/ecology.asp?si=16&fr=1&sts= [15 Nov 2007]

2.02

(1) NATIVE RANGE Southeast Asia, Philippines, China, and Japan

(1) http://www.nps.gov/plants/alien/fact/imcy1.htm [15 Nov 2007]

2.03

(1) Hardiness: USDA Zone 6a: to -23.3 °C (-10 °F) USDA Zone 6b: to -20.5 °C (-5 °F) USDA Zone 7a: to -17.7 °C (0 °F) USDA Zone 7b: to -14.9 °C (5 °F) USDA Zone 8a: to -12.2 °C (10 °F) USDA Zone 8b: to -9.4 °C (15 °F) USDA Zone 9a: to -6.6 °C (20 °F) USDA Zone 9b: to -3.8 °C (25 °F)

(1) http://davesgarden.com/guides/pf/go/776/ [15 Nov 2007]

2.04

(1) Native range: A native to southeast Asia, I. cylindrica is found throughout the temperate and tropic zones. The exact center of origin of I. cylindrica is in doubt, but is believed to be East Africa (Evans 1987 1991, in Van Loan Meeker and Minno 2002). It is found mainly in tropical and subtropical areas with 75 to 500 cm of annual rainfall. It has been found at latitiudes from 45°N (Japan) to 45°S (New Zealand), and from sea level to over 2,000 m elevation

(1) http://www.issg.org/database/species/ecology.asp?si=16&fr=1&sts= [15 Nov 2007]

2.05

(1) Native range: A native to southeast Asia, I. cylindrica is found throughout the temperate and tropic zones. The exact center of origin of I. cylindrica is in doubt, but is believed to be East Africa (Evans 1987 1991, in Van Loan Meeker and Minno 2002). It is found mainly in tropical and subtropical areas with 75 to 500 cm of annual rainfall. It has been found at latitiudes from 45°N (Japan) to 45°S (New Zealand), and from sea level to over 2,000 m elevation

(1) http://www.issg.org/database/species/ecology.asp?si=16&fr=1&sts= [15 Nov 2007]

3.01

(1) Known introduced range: Commonly found in humid tropics I. cylindrica has spread to warm temperate zones worldwide (Hubbard et al. 1944, in Langeland and Burks 1998). It is widely distributed in Africa, Australia, southern Asia, and the Pacific Islands, and less extensively distributed, or a less serious problem, in southern Europe, the Mediterranean, the Middle East, Argentina, Chile, Colombia, the Caribbean, and the southeastern United States (Van Loan Meeker and Minno 2002).

(1) http://www.issg.org/database/species/ecology.asp?si=16&fr=1&sts= [15 Nov 2007]

3.02

(1) Cogon grass can invade and overtake disturbed ecosystems, forming a dense mat of thatch and leaves that makes it nearly impossible for other plants to coexist.[disturbance weed not scored because yes for 3.04]

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007]

3.03

(1) Considered one of the top 10 worst weeds in the world, reported by 73 countries as a pest in a total of 35 crops

(1) http://www.fleppc.org/ID_book/Imperata%20cylindrica.pdf [15 Nov 2007]

3.04

(1) Dry and vast Imperata wastelands are highly prone to frequent and intense fires, which destroy native vegetation and hamper the succession of native plants by killing shoots (Eussen and Wirjahardja 1973; Dela Cruz 1986 in Jussi et al. 1995).

(1) http://www.issg.org/database/species/ecology.asp?si=16&fr=1&sts= [15 Nov 2007]

3.05

Although several other Imperata spp. are listed as weeds of some sort, there is no information documenting actual impacts. For example, Imperata brasiliensis is listed as a noxious weed, but the following information indicates that information on ecosystem level effects is lacking. (1) Brazilian satintail occupies pine (Pinus spp.) and oak (Quercus spp.)-pine communities of the Southeast. Descriptions of southeastern plant communities infested with Brazilian satintail were not found in the literature. Studies to determine if and how Brazilian satintail affects composition and diversity of such plant communities are needed.

(1) http://www.hear.org/gcw/scientificnames/scinamei.htm [16 Nov 2007)

4.01

(1) Cogon grass grows to 3 feet (1 m) in height. Leaves are mostly basal, growing from the rhizomes. Basal leaves are 0.4 to 0.8 inch (1-2 cm) wide. A few small upper leaves occur on the pedestal. The leaves have a characteristic white midrib that is set off-center. Being high in silica, cogon grass leaves are coarse in texture. The inflorescence is a dense, 4- to 8-inch (10-20 cm) panicle of paired spikelets. Spikelets are unawned with long (~12 mm), silky hairs. The seeds are small (1-1.3 mm long).  

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS [16 Nov 2007}

4.02

(1) Another mechanism by which cogongrass maintains dominance is through allelopathy. Cogongrass has been reported to suppress the growth of crops (Hubbard et al., 1944; Soerjani, 1970). Eussen et al. (1976), Eussen and Soerjani (1975) and Eussen (1979) in a series of experiments showed that cogongrass suppressed the growth of tomato and cucumber and that the factor(s) involved were more active at lower pH (Eussen and Wirjahardja, 1973). Studies have also demonstrated potential allelopathy by cogongrass (Eussen, 1979; Casini et al., 1998; Koger and Bryson, 2003). [cannot differentiate from direct competition] (2) Cogon grass allelopathy has been implicated in laboratory experiments; however, such claims are based upon research using cogon grass extracts at concentrations that do not occur under field conditions. Reputed allelopathy of cogon grass awaits reciprocal transplant experiments in the field and/or greenhouse.

(1) MacDonald, G. E. 2004. 'Cogongrass (Imperata cylindrica) - Biology, Ecology, and Management', Critical Reviews in Plant Sciences, 23:5, 367 - 380 (2)http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS [16 Nov 2007}

4.03

(1) Cogon grass causes physical injury when its rhizome tips, which are as sharp as its leaves, penetrate the roots of other herbaceous species, sometimes forming a parasitic relationship with the injured plant [the relevant reference describes this phenomenon as rare "Ghosal, Shibnath; Kumar, Yatendra; Chakrabarti, Dilip K.; Lal, Jawahar; Singh, Sushil K. 1986. Parasitism of Imperata cylindrica on Pancratium biflorum and the concomitant chemical changes in the host species. Phytochemistry. 25(5): 1097-1102. --A rare incidence of phanerogamic parasitism of Imperata cylindrica on Pancratium biflorum and the concomitant changes in the chemical constituents, from the hypersensitive responses in the host species, are reported -- has never been reported since the original study]

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS [16 Nov 2007] References cited for this question include the following: (a). Boonitee, A.; Ritdhit, P. 1984. Allelopathic effects of some weeds on mungbean plants. In: Proceedings, 1st Pacific Weed Science Society conference; [Date of conference unknown]; Songkla, Thailand. 2: 401-406. (b) Coile, Nancy C.; Shilling, Donn G. 1993. Cogongrass, Imperata cylindrica (L.) Beauv.: a good grass gone bad! Botany Circular No. 28. Gainesville, FL: Florida Department of Agriculture and Consumer Services, Division of Plant Industry. 3 p.(c) Ghosal, Shibnath; Kumar, Yatendra; Chakrabarti, Dilip K.; Lal, Jawahar; Singh, Sushil K. 1986. Parasitism of Imperata cylindrica on Pancratium biflorum and the concomitant chemical changes in the host species. Phytochemistry. 25(5): 1097-1102.

4.04

(1) Palatability: Cogon grass is relatively unpalatable and unnutritious for livestock and North American wildlife [39,40,43,58,86]. It is lower in nitrogen and higher in fiber and silica compared to native wiregrasses (Aristida spp.) of the Southeast [23,25,86]. The leaf blades are sharp and rough at the edges, discouraging animals from grazing [25]. New spring growth and postfire sprouts are palatable to livestock for 3 to 4 weeks; however, plants become coarse and fibrous after that [160]. In a rangeland study in subtropical Australia, cogon grass cover increased in response to cattle grazing at the expense of common carpet grass (Axonopus fissifolius), which is more palatable and nutritious [60]. Stober [139] described cogon grass as unpalatable to domestic sheep in Malaysia; however, domestic sheep can learn to graze cogon grass [156].

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS [16 Nov 2007}

4.05

(1) No evidence.

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS [16 Nov 2007}

4.06

(1) Cogon grass has several insects and fungal pathogens that infest it in Asia [35]. Two fungal pathogens (Bipolaria sacchari and Drechslera gigantea) have shown potential as cogon grass control agents in greenhouse trials [177,178]. (2) Cogongrass has been shown to harbor locusts, and there is evidence that swards of this grass is a major breeding ground for these pests (Brook, 1989). Cogongrass is also host to several polyphagous insects in cereals and an alternative host of the rust Puccinia refipes diet (Chandrasrikul, 1962; Vayssiere, 1957).[Puccinia refipes is not an economically important pest and others are polyphagous or generalists]

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS [16 Nov 2007] (2) MacDonald, G. E. 2004. 'Cogongrass (Imperata cylindrica) - Biology, Ecology, and Management', Critical Reviews in Plant Sciences, 23:5, 367 - 380.

4.07

(1) Previous studies have established the role of Imperata cylindrica (Ic) pollen in type I allergic disorders. (2) The 20 control had negative responses to patch testing. 5 out of 46 patients had positive patch tests to Axonopus compressus (carpet grass). Ischaenmum muticum (sea-shore centipede grass). Imperata evlindrica (lalang). Panicum maximum (Guinea grass) and Pennisetum purpureum (elephant grass). [no evidence of impact on people -- skin test is not indicitive of real-world symptoms caused by this species]

(1) Kumar, L., S. Sridhara, B.P. Singh, S.V. Gangal. 1998. Characterization of Cogon Grass (Imperata cylindrica) Pollen Extract and Preliminary Analysis of Grass Group 1, 4 and 5 Homologues Using Monoclonal Antibodies to Phleum pratense. International Archives of Allergy and Immunology 117:174-179. (2) Koh, D., C. L. Goh, H. T. W. Tan, S. K. Nge, W. K. Wong. 1997. Allergic contact dermatitis from grasses. Contact Dermatitis 37 (1), 32–34.

4.08

(1) Large infestations of cogon grass can alter the normal fire regime of a fire-driven ecosystem by causing more frequent and intense fires that injure or destroy native plants. (2) Cogon grass changes fuel properties in pinelands of the Southeast. As a tall, rhizomatous grass on sites historically dominated by bunchgrasses, cogon grass produces more standing biomass and litter than native bunchgrasses. Thus, it increases fuel loads and horizontal and vertical continuity. There is no evidence that there are differences in fuel chemistry between cogon grass and native bunchgrasses [15,87].
Fuel load estimates are needed for cogon grass-dominated sites in the United States. Fuel load measurements in native cogon grasslands may serve as a 1st-step basis for estimating fuel loads in the southeastern United States. Pickford and others [111] conducted fuel sampling in burned and unburned forest-mangrove (Acacia mangium)/cogon grass stands in Indonesia. They provide fuel loading and fire behavior information (base

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007] (2) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#FIRE%20ECOLOGY [16 Nov 2007]

4.09

(1) Cogon grass is a hardy species, tolerant of shade, high salinity and drought. (2) Cogon grass cannot tolerate deep shade [14,100], but can survive in the moderate shade of savannas [63,64].

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007]

4.1

(1) While congon grass is tolerant of a wide variety of soil conditions (including variations in fertility, organic matter and moisture) it grows best in relatively acidic soils (pH 4.7)

(1) http://www.issg.org/database/species/ecology.asp?si=16&fr=1&sts= [15 Nov 2007]

4.11

No evidence.

4.12

(1) In Southeast Asia, rhizomes typically occur 4 to 20 inches (10-40 cm) below ground and form dense, extensive layers. Some rhizomes grow as deep as 3 feet (1 m) [8,100]. Cogon grass's growth habit is loose to clumped, compacted aerial stems arising from the dense rhizome mat [34,43]. Dense stands may form monocultures [43,87].

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#GENERAL%20BOTANICAL%20CHARACTERISTICS [16 Nov 2007]

5.01

Terrestrial

5.02

Poaceae

5.03

5.04

(1) The root system is fibrous. Cogon grass rhizomes are "tough and scaly," with short internodes forming a dense underground mat. Cogon grass rhizomes develop in 2 stages: primary seedling rhizomes, and secondary rhizomes that sprout from seedling rhizomes

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS [16 Nov 2007]

6.01

No evidence. (1) Imperata cylindrica var. major shows considerable diversity in reproductive morphology and physiology in Asia ([14] and references therein),[124,146].

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS [16 Nov 2007]

6.02

(1) Cogon grass reproduces both vegetatively and from seed. A single plant can produce several thousand very small seeds that may be carried great distances by the wind. (2) Cogon grass reproduces from seed, rhizome expansion, and rhizome fragments [43,86]. Both seed and rhizome regeneration are important in its spread. Seed reproduction allows for long-distance dispersal and colonization, whereas rhizome spread is the primary means of population expansion [56,64]. Transported rhizome fragments also contribute to its long-distance dispersal and colonization [86].

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007] (2) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#GENERAL%20BOTANICAL%20CHARACTERISTICS [16 Nov 2007]

6.03

(1) Brazilian satintail and cogon grass are morphologically and genetically very similar, and their hybrids produce fertile offspring [57,133,165]. Hybridization, introgression, and overlapping morphological characters often cause taxonomic confusion between the 2 species, especially in North America. Some systematists consider the 2 species synonymous [24,57]. Hall [57] suggests that Brazilian satintail be classified as an infrataxon within I. cylindrica. Gabel [43] separates the taxa as 2 distinct species based upon continents of origin and morphological, cytological, and genetic attributes. This review treats Brazilian satintail and cogon grass as 2 distinct species.

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html#TAXONOMY [16 Nov 2007]

6.04

(1) Seed production from populations in Florida was shown to be self-incompatible; only cross-pollination from geographically isolated, heterogenous populations produced viable seeds.

(1) McDonald, S. K., Shilling, D. G., Bewick, T. A., Okoli, C. A. N., and Smith, R. 1995. Sexual reproduction by cogongrass, Imperata cylindrica. Proc. South. Weed Sci. Soc. 48: 188.

6.05

(1) Pollination: Cogon grass is pollinated by wind [94,133].

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#GENERAL%20BOTANICAL%20CHARACTERISTICS [16 Nov 2007]

6.06

(1) Cogon grass reproduces both vegetatively and from seed. Vegetative spread of cogon grass is aided by its tough and massive rhizomes that may remain dormant for extended periods of time before sprouting. Rhizomes of cogon grass may be transported to new sites in contaminated fill dirt or by equipment used in infested areas.

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007]

6.07

Possibly within one year, but no specific information on actual time to flowering was found. (1) Flower production: Cogon grass flower production is highly variable. Some researchers report cogon grass as highly productive [43], but flowering is often sporadic, ranging from none to frequent flowering within and among populations [33,43,106,170]. In a common garden study using Malaysian collections, some cogon grass populations frequently produced flowers; others never produced flowers (but spread vegetatively); while most produced flowers only after mowing disturbance [125]. Disturbances including nitrogen amendment, slashing, burning, defoliation, and grazing may trigger cogon grass flowering [43,63]. However, Shilling and others [133] found consistent flowering in 11 Florida cogon grass populations, none of which were disturbed. Field and greenhouse studies suggest that cogon grass flowering is not photoperiod dependent [133].

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#GENERAL%20BOTANICAL%20CHARACTERISTICS [16 Nov 2007]

7.01

(1) Rhizomes of cogon grass may be transported to new sites in contaminated fill dirt or by equipment used in infested areas. (2) Roads and road construction are important corridors for cogon grass dispersal [16,169]. Rhizomes are transported by machinery and fill dirt during construction [43,107]. Most long-distance dispersal of cogon grass is probably from inadvertent human transport of rhizomes and seeds [86]. Willard and others [169,170] speculated that cogon grass spread in Florida was mostly from transporting soil contaminated with cogon grass propagules.

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007] (2) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#GENERAL%20BOTANICAL%20CHARACTERISTICS [16 Nov 2007]

7.02

Ornamental plant (1) Clump-forming grass with mid-green leaves which turn blood-red from the tips downwards. This spectacular grass is very unusual and provides a wonderful contrast to golden, blue or black foliaged grasses in the border or a container. (2) Another important aspect in the area of prevention is the concern over the sale of cogongrass var. Rubra, or var. koenigii. This variant is widely promoted as an ornamental grass under the names Rubra, Red Baron, and Japanese Blood Grass. These varieties have been reported as nonaggressive, but research by Greenlee (1992) and Bryson (personal communication) suggested plants revert to the green, invasive form. The greatest concern, however, is the potential for hybridization between ornamental ecotypes and weedy biotypes found in the southern U.S. The ornamental varieties have been shown to survive as far north as Indiana, and this could dramatically extend the host range of this invasive species.

(1) http://www.gardeningexpress.co.uk/ProductDetails.asp?ProductID=10577 [16 Nov 2007] (2) MacDonald, G. E. 2004. 'Cogongrass (Imperata cylindrica) - Biology, Ecology, and Management', Critical Reviews in Plant Sciences, 23:5, 367 - 380.

7.03

(1) Cogongrass invades and persists in moist tropical areas because of extensive deforestation and fire-based land utilization systems (Holm, 1969, Islam et al., 2001). It is considered a primary weedy species in tea (Camillia sinesis L.), rubber (Hevea spp.), pineapple (Ananas comosus Merr.), coconut (Cocos nucifera L.), oil palm (Elaeis spp.), and other perennial plantation crops in Asia, whereas in Africa it causes the greatest damage in agronomic production (Ivens, 1980). In other areas, cogongrass infests natural habitats, destroying many native plant ecosystems in the southeastern U.S.

(1) MacDonald, G. E. 2004. 'Cogongrass (Imperata cylindrica) - Biology, Ecology, and Management', Critical Reviews in Plant Sciences, 23:5, 367 - 380.

7.04

(1) A single plant can produce several thousand very small seeds that may be carried great distances by the wind. (2) Seed/rhizome dispersal: Cogon grass seed is spread by wind. The seeds are small and light weight, with long, hairy plumes aiding wind carriage [43,94,133,164]. Cogon grass seeds may drift 15 miles (20 km) in open country [64]. Shilling and others [133] showed that wind can disperse cogon grass spikelets up to 360 feet (110 m) from the parent plant. Cogon grass spread in Alabama from 1973 to 1985 was apparently due to northeasterly prevailing winds from the Gulf of Mexico blowing seeds up Interstate 65 [164,165].

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007] (2) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#GENERAL%20BOTANICAL%20CHARACTERISTICS [16 Nov 2007]

7.05

No evidence

7.06

(1) Both seed and rhizome regeneration are important in its spread. Seed reproduction allows for long-distance dispersal and colonization, whereas rhizome spread is the primary means of population expansion [56,64]. Transported rhizome fragments also contribute to its long-distance dispersal and colonization [86].

(1) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#GENERAL%20BOTANICAL%20CHARACTERISTICS [16 Nov 2007]

7.07

No evidence, although it seems probable that seeds would be dispersed externally on the fur or feathers of animals.

7.08

No evidence. (1) During the dry season, the common grass I. cylindrica flowers and fruits immediately after the fires, and is dispersed by wind.  After dispersal the grass send up new shoots at which time it is heavily grazed by rhinoceros and other ungulates, the direct opposite of the FAF strategy [Author argues that Imperata cylindrica seeds are not dispersed by animals, but this is not evidence that seeds would or would not survive passage through gut] [Grass was rated as not palatable (4.04) so consumption of mature inflorescences by grazers is not a reasonable expectation]

(1) Dinerstein, E. 1989. The Foliage-as-Fruit Hypothesis and the Feeding Behavior of South Asian Ungulates. Biotropica 21(3): 214-218.

8.01

(1) Seed production in early spring with up to 3000 seed per seedhead, most of which are viable.

(1)Holm LeRoy, Doll Jerry, Holm Eric, Pancho Juan, Herberger James. 1997. World Weeds: natural histories and distributions. John Wiley and Sons. New York. Pg 693

8.02

(1) Seedling emergence from soil samples collected in naturally infested sites lasted only 3 mo following flowering. A high proportion (>90%) of seeds stored in cool, dry conditions remained viable for up to 3 mo, after which seeds quickly lost viability, dropping to 50% by 7 mo and to 0 by 11 mo. (2) Seed banking: Cogon grass seed is short lived, generally remaining viable in the soil for about 1 year [50]. Viability of seeds stored in a laboratory steadily decreased over 13 months [33]. Field studies in Asia show a maximum seed life of 16 months [124,125].

(1) Shilling, D. G., T. A. Bewick, J. E Gaffney, S. K. McDonald, C. A. Chase, and E.R.R.L. Johnson. 1997. Ecology, Physiology. and Management of Cogongrass (Imperata cylindrica). Final Report. Florida Institute of Phosphate Research. 128 p. (2) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html
#GENERAL%20BOTANICAL%20CHARACTERISTICS [16 Nov 2007]

8.03

(1) The best time to apply herbicides is in the early fall before first frost.  A 2% solution of glyphosate (e.g., Roundup®) is recommended in areas that will be immediately revegetated, because glyphosate has no residual soil activity. In areas where immediate revegetation is not planned, and non-target plant damage is not a concern, application of a 1-1.5% solution of imazapyr (e.g., Arsenal®) may be considered.

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007]

8.04

(1) Burning has also been used successfully in controlling cogon grass. As with mowing, burning stimulates the growth and spread of cogon grass, making followup control a necessity. (2) Rhizomes sprout readily after mowing, grazing, or burning removes top-growth [8]. A low root:rhizome ratio aids in rapid regrowth after fire or mowing [124]. In a growth chamber study, Ayeni and Duke [8] found old, large rhizome segments showed best stem sprouting and biomass gain compared to small, younger rhizome segments.

(1) http://www.nps.gov/plants/alien/fact/pdf/imcy1.pdf [15 Nov 2007] (2) http://www.fs.fed.us/database/feis/plants/graminoid/impspp/all.html [16 Nov 2007]

8.05

Don't know, but probably not.