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Discussion 
Mr. R. de Milde (Belgium): Is there a special reason why you did not use infrared photo 
graphy? Answer: With panchromatic film we are able, on that scale, to recognize the different 
tree species. Infrared photos would give no further information. Mr. de Milde : And in case 
of regeneration? Answer: In that case infrared photos would probably be more useful for species 
recognition. 
Mr. D. A. Boon (Netherlands): Are these large scale photos only to be used for species recogni 
tion? Answer: We hope to use them for measurements, but until now we have many difficulties 
with the scale determination. Mr. Boon: How was the flying done? Answer: In strips. The 
planning was not very accurate for the photos were not to be used on a practical base. 
Dr. D. A. Francis (U.K./FAO): Have yeu used the Airborne Profile Recorder for scale 
determination? Answer: Not yet.