Detection and Eradication of Giant Asian Dodder (Cuscuta japonica Choisy), a Parasitic Invasive Plant

K.S. Camilli, D.N. Appel, T. Kurdyla, R.F. Billings, and V. Cordova

University of Nevada-Reno (1), Texas A&M University Department of Plant Pathology and Microbiology (2,3), Texas Forest Service Forest Pest Management(4), City of Houston, Texas (5)

Giant Asian dodder (GAD), Cuscuta japonica, is an exotic, parasitic vine that is listed as a noxious, dangerous weed by the USDA APHIS.  This plant is native to Korea, Japan, China and Russia.  In 2001, infestations of GAD were detected at five locations in southeastern Houston, TX.  Prior to that discovery, GAD had been found and eradicated at three locations in the U.S. - in Florida (1943), Texas (1941), and South Carolina (1971).  Although numerous dodder species are native to Texas, including the curious tree dodder (C. exaltata), none has the destructive potential of GAD.  This potential derives from the parasite’s extremely high growth rate as well as its wide host range.  The discovery of GAD in Houston led to the formation of an inter-agency task force consisting of personnel with the Texas Forest Service, the Texas Agricultural Experiment Station, Texas Cooperative Extension, the City of Houston, and the USDA APHIS.  Circulars and posters describing this invasive plant were published in English, Spanish, Vietnamese, and Chinese for distribution in the various ethnic neighborhoods to increase detection and public awareness.  Intensive survey and mapping activities utilizing GPS and GIS were immediately initiated and a plan was formulated to eradicate the parasite at each location.  Seventeen different hosts, including live oak (Quercus virginiana), Arizona ash (Fraxinus velutina), Texas mulberry (Morus microphylla), and loblolly pine (Pinus taeda), were recorded throughout highly visible residential and commercial properties.  Eradication efforts consisted of roguing, selective pruning, chipping and burying of infested plant material.  Although these efforts have been deemed very successful, a new infestation was discovered in the summer of 2005 and promptly treated.  This project has been a model of how numerous agencies operating under a well-planned, coordinated response can successfully respond to the introduction of a highly destructive invasive plant.

corresponding author:

Kim S. Camilli
Dept. of Natural Resources & Environmental Science
Mail Stop (186)
University of Nevada
1000 Valley Road
Reno, Nevada 89512
775-784-1732
k_camilli@yahoo.com