Chestnut ink disease is a major threat to the orchards and areas with newly planted chestnut trees in Portugal. In this study, 460 ha of chestnut stands in north-east Portugal were selected as a test area for aerial photographic monitoring. A Cessna 150 aircraft, as the aerial platform, and a small format aerial colour photographic system, were used to survey the trees.
Results indicate that vegetative condition can be detected on 35 mm normal colour photographs. According to the aerial observations, 5.3% (9.6% for ground truth) of the trees were dead. Moreover, 21.2% (21.9%) of the canopies had sparse and yellow foliage. Overall, the general level of damage was 1.90 (1.93) on a 0-4 scale (0=healthy).
No significant differences were found between the results of the ground surveys and aerial photographic observations. Therefore, small format aerial photography may be an effective and inexpensive tool to assess stress conditions associated with dieback diseases in chestnut stands.