Detection of Leafy Spurge (Euphorbia esula) Using Multidate High-Resolution Satellite Imagery

Abstract

Leafy spurge is a deep-rooted perennial weed that displaces native rangeland vegetation and replaces forage for cattle and other forages used by vertebrate herbivores. Strategic planning to control this weed requires monitoring its distribution and spread. Classical monitoring techniques, which often involve extensive ground survey efforts, can be aided by the synoptic nature of remotely sensed imagery. This research addresses the use of Space Imaging's 4-m multispectral Ikonos imagery for the survey and detection of leafy spurge infestations. Survey data were collected at a site in western North Dakota and used to produce supervised classifications of leafy surge infestations with Ikonos imagery. Multiple image dates per year were combined with each other to assess the added accuracy afforded by multitemporal imagery. Finally, individual patches of leafy spurge were analyzed to determine the minimum patch size and percent cover that were detectable with supervised classification of Ikonos imagery. Under some circumstances, the imagery was effective at detecting leafy spurge, but in areas with a higher forb component, the classification was not as effective. Multidate imagery provided increased accuracy, but improvements were not consistently significant. Leafy spurge infestations of <30% cover and 200 m2were not reliably detected.

Discriminating cropping systems and agro-environmental measures by remote sensing

“…Casady et al (2005) mapped Euphorbia esula infestations using multidate high-resolution satellite imagery. Anderson et al (1993), using multispectral images of the SPOT satellite, characterised the Ericameria austrotexana infestation in a ranch of 4400 has in southern Texas (USA).…”

IKONOS Image-Based Extraction of the Distribution Area of Stellera chamaejasme L. in Qilian County of Qinghai Province, China

“…The image includes four multispectral bands and one panchromatic band and the gray level is 2048 (11 bits). Table 1 shows band information for the IKONOS image [43,47]. 2.4.…”

Weed mapping using a machine vision system

“…In continuous weed sampling, data are collected over the entire field by using visual or remotely sensed imagery by an expert. Weed remote sensed images can be acquired by aircraft and satellite platforms (Bajwa & Tian, 2001;Casady et al, 2005;Cuneo et al, 2009) or tractor-based systems, known as machine vision systems (Lee et al, 1999;Lamm et al, 2002). In discrete weed sampling, data are collected only from pre-defined sites throughout the field and interpolation method is used to estimate weed infestation for the entire field (Expósito et al, 2003).…”