Site specific information on the foliage shape and size of orchard trees is a major factor in determining spray dosage for plant protection and crop coefficients for irrigation scheduling. A computerized map of each individual tree in the orchard is required to adjust irrigation emitters and variable spray volumes. In a feasibility study conducted at the Matityahu Experimental Farm in 1998, aerial photogrammetry was used to facilitate fast and affordable tree shape and volume mapping. Light interception cross-sections and gap frequency analysis was used for ground measurements of trees. Panchromatic, 1:4000 scale, 100 lines/mm resolution stereoscopic aerials served for analog photogrammetric processing. Tree contours and row cross-sectional area compared well between aerial- and ground-based measurements. Resulting tree volume maps seems to be sufficient for current applications in plant protection and irrigation scheduling. Further development of the method using multiple wavelength measurements will probably be needed in order to obtain estimates of foliage density and LAI.
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