In late 2013, a colleague of mine started development of a spatially-enabled, economic model for harvesting, transporting, processing, and marketing deliverables for Eastern Redcedar, an invasive evergreen species across the Great Plains region. To inform its spatial aspects, the model relied heavily on Redcedar canopy cover maps created by the Natural Resources Conservation Service (NRCS) between 2002 and 2005 for 18 Oklahoma counties. These maps served as a good start for the model, but because the model relied so heavy upon the Eastern Redcedar location and stand density, it was important that this information be accurate and up-to-date. Data collected in 2005 for a rapidly-spreading, invasive species was less than ideal for informing decisions about an industry based on that species. The dated and coarse nature of the NRCS maps made it necessary to collect more recent and higher quality data on the occurrence of Eastern Redcedar in Oklahoma.
To help with data improvement and as part of a course project, I worked to establish a methodological framework for identifying Eastern Redcedar by first identifying it in a single county, Payne County. Using imagery from the USDA Farm Service Agency’s (FSA) National Agriculture Imagery Program (NAIP), I conducted a supervised image classification to differentiate Eastern Redcedar within the imagery from other land cover types. This classification identified approximately 71,660 acres of Eastern Redcedar in Payne County and had an overall accuracy of 53%.
This project went a long ways towards developing usable Eastern Redcedar coverage data for Payne County, Oklahoma, for use in my colleague’s model, but since it was a course project that had to be completed within a very limited time frame and with no funding, the final results are limited. The biggest improvement I would like to make would be to take GPS points of actual Eastern Redcedar trees to better inform the classification process and then, eventually, perform the analysis for the entire state.
View larger slideshow here.
For a more in-depth look at this project, visit my course project website.