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Publications and source records attributed to Blazquez, C. H..
Handbook advises on benefits and methods of aerial photography with color infrared film. Interpretation of photographs is discussed in detail. Necessary equipment for interpretation is described--light table, magnifying lenses, and microfiche viewers, for example. Advice is given on rating tree condition; identifying effects of diseases, insects, and nematodes; and evaluating effects of soil, water, and weather.
Repetitive aerial photography with color infrared (ACIR) and black-and-white infrared (B and WIR) films was taken of potato and tomato fields in southwest Florida during the spring season of 1975. Color differences observed in the photographs revealed different levels of soil moisture in the fields, improper ditch arrangements, poor stands of plants, and areas where late blight (Phytophthora infestans) (Mont.)d.By and early blight (Alternaria solani) (Ell. and Mart.) Jones and Grout. were defoliating potato plants. Photographs of fields before planting also indicated areas where excessive rock formations existed which would make field preparation costly. Preplanting photographs also pinpointed areas with different water table levels.
Detection and disease damage assessment of citrus tree losses in a Florida citrus grove were made by establishing a registration (grove site location) coordinate system, developing a damage assessment system, and testing sequential aerial color infrared (ACIR) photography at the scale of 1 in. = 333 ft (2.5 cm = 100 m) during the winter, spring, and summer seasons of 1978 and spring of 1979. Spring photography was the easiest to photo interpret, showed the greatest differences between healthy and diseased trees, and had the least shadow and background interference for photo interpretation. Trees showing slight disease damage were detected in ACIR before they were found in ground surveys.
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Results of a one-year experimental study on the use of aerial color infrared photography in citrus grove management are presented. It is found that the spring season, when trees are in flush (have young leaves), is the best season to photograph visible differences between healthy and diseased trees. It is also shown that the best photography can be obtained with a 12-in. focal length lens. The photographic scale that allowed good photo interpretation with simple inexpensive equipment was 1 in. = 330 ft. The use of a window-overlay transparency method allowed rapid photo interpretation and data recording in computer-compatible forms. Aerial color infrared photography carried out during the spring season revealed a more accurate status of tree condition than visual inspection.