SURVEY AND DEVELOP MANAGEMENT PRACTICES FOR INVASIVE PLANT SPECIES IN GUAM.

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: MCINTIRE-STENNIS
• Reporting Frequency: Annual
• Accession No.: 0218111
• Project Start Date: May 1, 2009
• Project End Date: Oct 1, 2012
• Program Code: [(N/A)]- (N/A)

Recipient Organization
UNIVERSITY OF GUAM UOG STATION
(N/A)
MANGILAO,GU 96913

Performing Department
Experiment Station

Non Technical Summary
The accidental or intentional introduction of many herbs, shrubs, vines and trees for ornamental and other purposes have had a profound effect on the environment in Guam and Micronesia. Due to the absence of their natural enemies which would normally keep a balance in nature, these plants have become dominant in the ecosystem. Lee (1974) stated that invading plants originating in the New World outnumber those from the Old World in Guam and found that the invading species of plants were 3.4 percent in limestone forest, 9.4percent in ravine forest, 13.3 in savanna, 17.3 percent in strand and 32.4percent in wetland ecosystems. McConnell and Muniappan (1991) listed 12 species of introduced ornamental plants that became weeds in Guam. As most of these invaders are exotic species, many of them could be suppressed by the use of integrated pest management (IPM) measures.

Animal Health Component

(N/A)

Research Effort Categories

Basic

(N/A)

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
216	0640	1070	100%

Knowledge Area
216 - Integrated Pest Management Systems;

Subject Of Investigation
0640 - Tropical forests;

Field Of Science
1070 - Ecology;

Keywords

invasive plants

integrated pest management

survey

Goals / Objectives
1.Identify most serious invasive plants in Guam and the best control or eradication method. 2.Estimate total areas infested and project the rate and direction of spread. 3.Develop management recommendations for the major serious invasive plants. 4.Produce a listing of all the inventoried invasive plants in Guam.

Project Methods
Utilizing a standardized database and data collection requirements, information will be compiled from current and past surveys, expert knowledge, publications, past control programs. Location information (maps) will be compiled and entered into GIS for potential authentication. Utilizing an existing risk rating system (such as Hawaii's), a risk rating for all of the known or suspected species will be developed. The current situation of invasive species will be evaluated and available management methods will be described and recommended. Using a 12 channel global positioning system (GPS) (Garmin Corp., Taiwan), map out fixed survey areas in which invasive species are found, estimate total area infested and to project the rate and direction of spread via surveys and monitoring for 20 acres. Twenty villages will be selected for the survey work. This is to learn whether a particular invasive plant species is a generalist or specialist in various place places in Guam. Within each village, a 1-acre area (consisting of forest, disturbed area or roadside) will be identified, and within this, 10 different sites will be randomly chosen to assess the population of invasive plants occurring in the different habitat types. Line intercept transect method (Brower, and Zar. 1984) quadrat (1 by 1-m) will be used as a standard measure for the ecological study and was laid flat among invasive plants in the 10 random field areas to identify the plants. Invasive plants falling within the perimeter of the quadrat will be identified and the total number of each invasive plant will be counted and recorded on a data sheet. Based on the results of Objectives 1 and 2, recommendations will be made to the Government for management of the high risk weed species (eradication, control, containment). Any management recommendations will follow the concepts of Integrated Pest Management (IPM) and may involve one or more components of IPM including biological, chemical, cultural, legislative and mechanical controls. Conduct detailed surveys and produce a listing of all inventoried invasive plants in Guam. A detailed island wide survey (20 villages, in each village one acre of land) will be conducted to identify high risk invasive plant species and a list will be prepared. Surveys will run every other week and observations will be made in the fixed one acre plots for invasive plant species. Occurrence of invasive plants will be recorded on a data sheet along with other pertinent information.

Progress 05/01/09 to 10/01/12

Outputs
OUTPUTS: Survey and research on management practices for invasive plant species in Guam continued until P.I. resigned in 2012. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Results impacted management practices for pest control on Guam.

Publications

• No publications reported this period

Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: A previous survey of invasive plants on Guam identified the 20 most widespread. A biological control program has been initiated to control these invasive plant species on Guam. Accordingly, several biological control agents were imported and released in Guam for the control of Chromolaena odorata, Coccinia grandis and Mimosa diplotricha that have been spread in agricultural and forestry areas. The control of C. odorata was achieved using the Pareuchaetes pseudoinsulata (Lepidoptera: Arctiidae) and Cecidochares connexa (Diptera: Tephritidae) on Guam. There was a remarkable reduction of plant height due to the success of C. connexa. PARTICIPANTS: Presentation to the Upward Bound's Summer School Program on Guam Invasive Insect Pests and Their Management, Upward Bound Program, University of Guam, June 27th 2011. Presentation to the Sixth Graders on Guam Invasive Insect Pests, Harvest Christian Academy, Barrigada, Guam, March 14th 2011. TARGET AUDIENCES: Reddy, G.V.P. 2012. 52nd Annual Meeting of the Weed Science Society of America, Waikoloa, Hawaii, February 6 to 9, 2012. Reddy, G.V.P. 2011. The 13th International Symposium on Biological Control of Weeds (ISBCW 2011), Waikoloa, Hawaii, September 11 to 16, 2011. Reddy, G.V.P., R. Kikuchi and R. Muniappan, 2011. The impact of two introduced biocontrol agents, Pareuchaetes pseudoinsulata (Lepidoptera: Arctiidae) and Cecidochares connexa (Diptera: Tephritidae), on Chromolaena odorata (Asteraceae) on Guam. 8th IOBC International Workshop on Biological Control and Management of Chromolaena odorata and Other Eupatorieae., Nairobi, Kenya, 1 to 5 November 2010.5 November 2010. University of Guam WPTRC Impact Report 2011, "Weeding out Invasive Species with Classical Biological Control", pp. 7 to 8, "Protecting Fruit Crops with Pheromones", pp. 21-22. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
A biological control program on C. grandis has been effective in Guam following the success achieved in Hawaii, through the introduction of the natural enemies Melittia oedipus (Lepidoptera: Sesiidae), Acythopeus burkhartorum (Coleoptera: Curculionidae) and Acythopeus cocciniae (Coleoptera: Curculionidae). At this moment, there are no infestations of C. grandis seen in Guam. Although Heteropsylla spinulosa (Homoptera: Psyllidae) established successfully at the release sites on Guam, it has yet to provide a significant control of M. diplotricha. Presently, a biological control program has been initiated for the control of Mimosa diplotricha, using rust-fungus Puccinia spegazzinii (Basidiomycotina: Uredinales). Additionally, the biological control programs will be extended to other neighboring Micronesian islands.

Publications

• Reddy, G.V.P., and R.S. Kikuchi, and R. Muniappan. 2012. The impact of Cecidochares connexa (Diptera: Tephritidae) on Chromolaena odorata (Asteraceae) in Guam. In: C. Zachariades, M. Day, R. Muniappan, and L. Strathie (eds), Proceedings of the Eighth International Workshop on Biological Control and Management of Chromolaena odorata and other Eupatorieae, Nairobi, Kenya, 1 to 2 November 2010. ARC, Pretoria, South Africa, in press.
• Reddy, G.V.P., R. Kikuchi, and J. E. Remolona. 2011. New mite species associated with certain plant species from Guam. Journal of Entomological and Acarological Research, Ser. II, 43: 41 to 46.
• Reddy, G.V.P., J.E. Remolona, C.M. Legdesog, and G. J. McNassar. 2012. Effective biological control programs of invasive plants on Guam, Proceedings of the XIII International Symposium on Biological Control of Weeds, Sep. 11 to 16, 2011, Hawaii, USA, in press.

Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: Our previous report indicated 20 most widespread invasive plants on Guam. Here, we describe the risk assessment for the 20 most widespread invasive plants identified on Guam and the best management practices available for them. The recommended mechanical control methods can be applied without regulation, but the chemical applications and biological-control agents must comply with legal requirements. PARTICIPANTS: Guam Department of Agriculture TARGET AUDIENCES: My poster presentation on the Guam's Top 20 Invasive Plants and Management was impressed by Guam Department of Agriculture and Extension workers and farming community. Reddy, G.V.P. 2011. 51st Annual Meeting of the Weed Science Society of America, Portland, OR, February 7-10, 2011. Reddy, G.V.P., R. Kikuchi and R. Muniappan, 2011. The impact of two introduced biocontrol agents, Pareuchaetes pseudoinsulata (Lepidoptera: Arctiidae) and Cecidochares connexa (Diptera: Tephritidae), on Chromolaena odorata (Asteraceae) on Guam. 8th IOBC International Workshop on Biological Control and Management of Chromolaena odorata and Other Eupatorieae., Nairobi, Kenya, 1-5 November 2010.5 November PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Bidens alba (high risk), Panicum maximum (high risk), Stachytarpheta jamaicensis (high risk), Antigonon leptopus (high risk), Paspalum paniculatum (possible risk), Miscanthus floridulus (possible risk), Euphorbia heterophylla (possible risk), Chromolaena odorata (high risk), Mikania micrantha (high risk), Synedrella nodiflora (possible risk), Chamaesyce hirta (possible risk), Mimosa pudica (high risk), Leucaena leucocephala (possible risk), Pennisetum polystachion (possible risk), Euphorbia cyathophora (possible risk), Sida rhombifolia (possible risk), Momordica charantia (low risk), Chrysopogon aciculatus (low risk), Chamaesyce hypericifolia (low risk), and Chloris barbata (low risk).

Publications

• Reddy, G.V.P., R. Kikuchi, J. E. Remolona, and N. Braganza. 2011. Risk assessments and management practices for the top 20 invasive plants recorded on Guam. Journal of Plant Protection Research 50: in press.
• Reddy, G.V.P., R. Kikuchi and R. Muniappan. 2011. The impact of two introduced biocontrol agents, Pareuchaetes pseudoinsulata (Lepidoptera: Arctiidae) and Cecidochares connexa (Diptera: Tephritidae), on Chromolaena odorata (Asteraceae) on Guam. Proceedings of the International Conference on Chromolaena odorata. Nairobi, Kenya, 1-5 November 2010.

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Invasive plants are introduced, nonnative species that thrive and spread spontaneously in areas beyond their natural range. They are characteristically adaptable and aggressive and have high reproductive capacity. Their vigor, combined with escape from their natural enemies, often leads to extensive outbreak populations. The many invasive species on Guam constitute a growing problem. A survey of invasive plants in five habitat types across the 20 municipalities of Guam identified the 20 most widespread. The 20 survey sites were chosen to be representative of the entire geographic area of the island; one was placed within the boundaries of each of Guam's 20 municipalities, which, together, cover the entire area of the island. The locations of the 20 sampling sites, determined with a 12-channel global positioning system. They were chosen to include forested areas, residential areas, roadsides, vacant lots, and agricultural areas. Within each 1-acre site, 10 one meter square plots were randomly chosen for assessment of the population of invasive plants occurring in the different habitat types. A line-intercept transect-method (Brower et al. 1998) quadrat (1 by 1-m) was used as a standard measure for the study and was laid flat over the vegetation on each of the 10 plots. Invasive plants falling within the perimeter of the quadrat were identified, and the total number of individuals of each was recorded. PARTICIPANTS: 1. Anne Marie LaRosa, Forest Health Coordinator, Institute of Pacific Islands Forestry, USDA Forest Service, 60 Nowelo St. Hilo, Hawaii 96720-0370. 2. Joseph Mafnas, Territorial Forester, Guam Department of Agriculture, Mangilao, Guam 96923. 3. Belmina I. Soliva, Forester I, Guam Forestry Department, Mangilao, Guam 96923. TARGET AUDIENCES: Forestry Division of the Guam Department of Agriculture. Local farmers. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
A survey in five habitat types across the 20 municipalities of Guam identified the 20 most widespread invasive plants as Bidens alba, Panicum maximum, Stachytarpheta jamaicensis, Antigonon leptopus, Paspalum paniculatum, Miscanthus floridulus, Euphorbia heterophylla, Chromolaena odorata, Mikania micrantha, Synedrella nodiflora, Chamaesyce hirta, Mimosa pudica, Leucaena leucocephala, Pennisetum polystachion, Euphorbia cyathophora, Sida rhombifolia, Momordica charantia, Chrysopogon aciculatus, Chamaesyce hypericifolia, and Chloris barbata. At present, the best option for managing them could required more work on the possibility of biological control and may be to adopt preventive and mechanical control methods.

Publications

• Reddy, G.V.P. 2010. The impact of two introduced biocontrol agents, Pareuchaetes pseudoinsulata (Lepidoptera: Arctiidae) and Cecidochares connexa (Diptera: Tephritidae), on Chromolaena odorata (Asteracea), Gordon Research Conference on Plant Herbivore Interactions, Galveston, TX, February 21 to 26, 2010. Presentation on the major invasive weeds in Guam its control, Guam Department of Agriculture, Mangilao, GU, February 16, 2010.
• University of Guam Impact Report 2009: Article on "Guam's Top 20 Invasive Plants" appeared.
• Reddy, G.V.P. 2010. Survey of invasive plants on Guam and identification of the 20 most widespread. Micronesica 41: in press.
• Muniappan, R., G.V.P. Reddy, and A. Raman, eds. 2009. Biological Control of Tropical Weeds using Arthropods. Cambridge University Press, Cambridge, UK, 495 pp.