General Impact
Alves (2003) state that, "Rottboellia cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al. 1977 ; Mercado 1978 ). According to Cepero and Rodriguez (1983) , Millhollon (1982 , 1992 ), and Morales and Fernandes (1985) , this species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawai‘i, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." The authors continue to state that, "The appearance and dispersal of R. cochinchinensis worries researchers and sugarcane producers in areas that do not yet have R. cochinchinensis because the weed might spread and adapt to their conditions. Because itchgrass biotypes have not been confirmed, the same kind of control is used in every region."
Chikoye et al. (2000) state that, "R. cochinchinensis is a very competitive weed with crops particularly maize and it has irritating hairs on its stem which makes it difficult to control manually in small-scale farms. It is also tolerant to most herbicides that are applied in cotton and maize fields."
Strahan et al. (2000a) states that, "R. cochinchinensis is a prolific seed producer with seeds that germinate throughout the growing season (Harger et al. 1980 ; Millhollon 1965 ; Pamplona and Mercado 1982 ), making it difficult to manage. The weed is very competitive, and over a 3-yr period it may reach densities that could prevent crop harvest (Harger et al. 1982 ). Although relatively shade intolerant, R. cochinchinensis has the capacity for high photosynthetic activity and growth rates when exposed to light (Patterson 1979 ). Although adapted to the tropics, R. cochinchinensis has the ability to grow, flower, and set seed under a wide range of environmental conditions, reaching 75 to 100% of its growth potential under the temperature regimes found in the Gulf Coast states, the lower Midwest, the South Atlantic states, and the Southwest (Patterson et al. 1979 )." Strahan et al. (2000a) states that, "The competitiveness of R. cochinchinensis may be related to its ability to extract nutrients from soil more efficiently than Z. mays (El-Shafey et al. 1975 )."
Strahan et al. (2000b) states that, " R. cochinchinensis is rated among the worst weeds in the world and is considered a serious problem in soybean (Glycine max (L.) Merr.), corn, cotton (Gossypium hirsutum L.), peanut (Arachis hypogaea L.), upland rice (Oryza sativa L.), and other crops in tropical regions of the world (Holm et al. 1977 ). In Louisiana, R. cochinchinensis, referred to as raoulgrass, is a major weed problem in sugarcane (Saccharum spp.), soybean, and corn (Millhollon 1965 )."
Location Specific Impacts:Argentina 
Agricultural: Alves (2003) states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Aramina (Brazil)
Agricultural: Alves (2003) state that, "R. cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al 1977 ; Mercado 1978 ). The author further states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Campinas (Brazil)
Agricultural: Alves (2003) state that, "R. cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al 1977 ; Mercado 1978 ). The author further states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Dumont (Brazil)
Agricultural: Alves (2003) state that, "R. cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al 1977 ; Mercado 1978 ). The author further states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Igarapava (Brazil)
Agricultural: Alves (2003) state that, "R. cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al 1977 ; Mercado 1978 ). The author further states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Jaboticabal (Brazil)
Agricultural: Alves (2003) state that, "R. cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al 1977 ; Mercado 1978 ). The author further states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Ribeirao Preto (Brazil)
Agricultural: Alves (2003) state that, "R. cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al 1977 ; Mercado 1978 ). The author further states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Cuba
Agricultural: Alves (2003) states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Honduras
Agricultural: Strahan et al (2000a) state that, "R. cochinchinensis left uncontrolled in Honduras reduced Z. mays yield 80% (Sharma and Zelaya 1986 )." India
Agricultural: Alves (2003) state that, "R. cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al 1977 ; Mercado 1978 ). The author further states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Mauritius
Agricultural: Alves (2003) state that, "R. cochinchinensis is an aggressive weed, considered to be one of the 12 worst weeds that infest sugarcane (Saccharum officinarum L.) in the world because it obstructs closure of crop rows when densities are above 10 plants m-2 (Holm et al 1977 ; Mercado 1978 ). The author further states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Trinidad and Tobago
Agricultural: Strahan et al (2000a) state that, "In Trinidad, Bridgemohan et al (1992) determined that in order to avoid yield loss, Z. mays must be maintained free of R. cochinchinensis competition for the first 9 wk after planting. The maximum length of time that Z. mays could withstand R. cochinchinensis competition before yield loss occurred was 1 wk after emergence." Hawaii (United States (USA))
Agricultural: Alves (2003) states that, "This species is one of the main invaders of sugarcane in Argentina, Cuba, India, Hawaii, Mauritius, Puerto Rico, Trinidad, and the United States, where losses can reach 20 to 70%, depending on the cultivar, cutting cycle, and local ecological conditions." Louisiana (United States (USA))
Competition: Strahan et al (2000a) state that, "R. cochinchinensis is highly competitive with Z. mays in Louisiana and, if allowed to compete all season, can reduce Z. mays yields as much as 38%." Strahan et al (2000a) further state that, "This weed has been declared noxious by Federal law and is commonly referred to as raoul grass in south Louisiana. It was first observed in Louisiana in 1927 near Ruth, St. Martin Parish (Millhollon 1975 )."
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