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Tanglehead (Heteropogon contortus) is a perennial grass native to Southwestern US rangelands; however, its prevalence as an invasive on South Texas rangelands has grown. In the last decade, large monotypic stands of tanglehead have emerged, simplifying native vegetative communities in Jim Hogg, Brooks and Kleberg Counties. The dominance of this species in sandy soils is a cause for concern for many ranchers as it may have negative impacts on wildlife resources. Unfortunately, little is known regarding the spatial extent of this invasion and its impact. The goal of this project is to determine the extent and spatial distribution of tanglehead in Jim Hogg and Duval Counties using freely available remote sensing platforms. The specific objectives are: (1) to determine the feasibility of classifying tanglehead from other vegetation types using National Agriculture Imagery Program (NAIP) aerial imagery and (2) to quantify the spatial and temporal distribution of tanglehead in critical areas identified by ranchers in South Texas. To achieve this goal, 22 color-infrared 1�meter resolution NAIP imagery (2014) were classified by combining the NAIP bands (red, green, blue, near infrared) with the normalized difference vegetation index (NDVI) to identify tanglehead from other land cover types (woody, non-tanglehead herbaceous, and bare soil) and assess its spatial distribution. The accuracy of the classified imagery was assessed using a confusion matrix. The overall accuracy exceeded the minimum national standard of 85%. This process was repeated for imagery available in 2008, 2010, and 2012. The changes observed in the spatial distribution of tanglehead between years will be compared and assessed. Accuracy assessments are currently being conducted for the 2008 � 2012 imagery and impacts of roads and soils in the distribution of tanglehead will be evaluated as well.