A study was conducted on the south Texas Gulf Coast to evaluate color-infrared (CIR) aerial photography and CIR true digital imagery combined with unsupervised image analysis techniques to distinguish and map black mangrove [Avicennia germinans (L.) L.] populations. Accuracy assessments performed on computer-classified maps of photographic and digital images of the same study site had both producer's and user's accuracies of 100% for black mangrove. An accuracy assessment performed on a computer-classified map of a digital image only of a second study site had a producer's accuracy of 78.6% and a user's accuracy of 100%. These results indicate that CIR photography and digital imagery combined with image analysis techniques can be used successfully to distinguish and quantify the extent of black mangrove along the south Texas Gulf Coast.