Accurate area determination of complex leaves using digital image analysis

A recently described computer image analysis method was modified for quanti fication of leaf area. These areas were compared to those estimated by a lo wer resolution method based on planimetry. Leaves of Eucalyptus nitens (Dea ne & Maiden) Maiden, pinnae of Dicksonia antarctica Labill. and leaves of A cacia dealbata Link were used for analysis, offering surfaces of low, inter mediate and high complexity, respectively. Low-resolution planimetry was fo und to be a suitable method for the calculation of leaf area of simple broa dleaves. However, for surfaces of greater complexity, the higher resolution of image analysis gave more accurate estimates of area. Overlapping of pri mary pinnae in the complex A. dealbata leaf proved to be a larger source of error than inadequacy of resolution.