Use of spatial information technologies for noxious plant detection and distribution on rangelands

This paper reviews the application of aerial photography, airborne videography, and satellite imagery for distinguishing brush and weed species on rangeland and other wildland areas in the western United States. Ground reflectance measurements are used to determine the spectral characteristics of plant species. Season is an important variable for detecting many species because their reflectance varies at different times of the year and many species are distinguishable only when in a specific phenological stage. Computer image analyses are used to quantify weed and brush infestations, thus providing area estimates of noxious plant populations on rangelands. The integration of videography with global positioning system and geographic information system technologies is demonstrated. Plant species addressed include silverleaf sunflower (Helianthus arqophyllus). Texas lantana (Lantana horrida), false broomweed (Ericameria austrotexana). broom snakeweed (Gutierrezia sarothrae). spiny aster (Aster spinosus). blackbrush (Acacia rigidula). huisache (Acacia farnesiana). Mexican palo‐verde (Parkinsonia aculeata). common goldenweed (Isocoma coronopifolia). Drummond goldenweed (Isocoma drummondii). Chinese tamarisk (Tamarix chinensis), pricklypear (Opuntia lindheimeri). leafy spurge (Euphorbia esula). Big Bend locoweed (Astragalus mollissimus), Wooton locoweed (Astragalus wootoni). sand sagebrush (Artemisia filifolia). and shin oak (Ouercus havardii).