Field testing Diorhabda elongata (Coleoptera: Chrysomelidae) from Crete, Greece, to assess potential impact on nontarget native California plants in the genus Frankenia.

When laboratory host specificity tests on weed biological control agents produce ambiguous results or are suspected of producing false-positive findings, field cage or open field tests can be used to help determine the true ecological host range of the agent. The leaf beetle Diorhabda elongata (Brullé) from Crete, imported to the United States for the control of saltcedar (Tamarix spp., Tamaricaceae), showed a low but variable ovipositional response to nontarget Frankenia spp.

Canopy assessment of biochemical features by ground-based hyperspectral data for an invasive species, giant reed (Arundo donax).

This study explored the potential use of hyperspectral data in the non-destructive assessment of chlorophyll, carbon, and nitrogen content of giant reed at the canopy level. We found that pseudoabsorption and derivatives of original hyperspectral data were able to describe the relationship between spectral data and measured biochemical characteristics. Based on correlogram analyses of ground-based hyperspectral data, we found that derivatives of pseudoabsorption were the best predictors of chlorophyll, carbon, and nitrogen content of giant reed canopies.

Invasive species change detection using artificial neural networks and CASI hyperspectral imagery.

For monitoring and controlling the extent and intensity of an invasive species, a direct multi-date image classification method was applied in invasive species (salt cedar) change detection in the study area of Lovelock, Nevada. With multidate Compact Airborne Spectrographic Imager (CASI) hyperspectral data sets, two types of hyperspectral CASI input data and two classifiers have been examined and compared for mapping and monitoring the salt cedar change. The two types of input data are all two-date original CASI bands and 12 principal component images (PCs) derived from the two-date CASI images.

Invasive species research in the United States Department of Agriculture-Agricultural Research Service.

Invasive pests cause huge losses both to agricultural production systems and to the natural environment through displacing native species and decreasing biodiversity. It is now estimated that many thousand exotic insect, weed and pathogen species have been established in the USA and that these invasive species are responsible for a large portion of the $130 billion losses estimated to be caused by pests each year. The Agricultural Research Service (ARS) has responded with extensive research and action programs aimed at understanding these problems and developing new management approaches for their control.