Stellera chamaejasme L.(Stellera) is a poisonous weed that widely distributed in grassland ecosystems of Western China.
Field reflectance measurements were performed for the Stellera with varied coverage in Qilian county of China. The
spectral characteristics of some main species were analyzed. The result indicated that the reflectance of the corolla of
Stellera was greater than that of other species over the full range of wavelengths. The best time to distinguish Stellera is
the full bloom period of the Stellera. Three groups of spectral measurements were performed for the Stellera with varied
coverage. The first experiment indicated that the reflectance increased with the increased densities in near-infrared
wavelengths, but no obvious regular pattern existed in visible bands. On the contrary, in the full bloom period of the
Stellera, there is an obviously increasing trend of reflectance both in visible and near-infrared bands with the increased
densities. No distinct trend was found in the third experiment that conducted after the full bloom period. A clear linear
relationship exited in analyzing the correlation between Stellera with varied density and their spectral characteristics.
Thus, the density of Stellera could be quantitatively estimated based on the spectral characteristics from hyperspectral
remote sensing images.