Submitted to: Weed Technology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/3/2003
Publication Date: 9/29/2004
Citation: Henry, W.B., Shaw, D.R., Reddy, K.R., Bruce, L.M., Tamhankar, H.D. 2004. Remote sensing to distinguish soybean from weeds following herbicide application. Weed Technology. p.594-604. Interpretive Summary: Remote sensing data can be used to distinguish between weeds and crop. In a field setting, there will be multiple variables that may influence the way that light reflects off of the plant leaves. One of these variables is herbicide application. Soybean and weed species were grown and herbicides were applied. Models were created that successfully distinguished between weeds and crop. These models are now ready to be applied to field data.
Technical Abstract: Experiments were conducted to examine the utility of hyperspectral remote sensing data for discriminating common cocklebur, hemp sesbania, pitted morningglory, sicklepod, and soybean following preemergence and postemergence herbicide application. Discriminant models were created from combinations of multiple indices. The model created from the second experimental run's data set and validated on the first experimental run's data provided an average of 97% correct classification of soybean and an overall average classification accuracy of 65% for all species. This suggests that these models are relatively robust and could potentially be used across a wide range of herbicide applications in field scenarios. From the pooled data set, a single discriminant model was created with multiple indices that discriminated soybean from weeds 88%, on average, regardless of herbicide, rate or species. Signature amplitudes, an additional classification technique, produced variable results with respect to discriminating soybean from weeds after herbicide application, and discriminating between controls and plants to which herbicides were applied; thus, this was not an adequate classification technique.