CHAPTER 5 CONCLUSIONS AND RECOMMENDATIONS 5.1 CONCLUSIONS 1. Ground level pressure measurements 2000 ft into a tree stand substantiate UPSHOT-KNOTHOLE conclusion of no attenuation in peak static overpressure; therefore, for this purpose further measurements of over- pressure in tree stands should not be necessary. 2. It was not possible to assess the stand influence by observation of damage because of non-uniformity of stand composition; nor was it possible to determine the peak dynamic pressure attenuation because the three gages in or near the stands showed large unexplained variation. 3. Observed damage from two weapons of different yields compare favorably with isodamage curves prepared ror broadleaf stands. 4. Demage in broadleaf stands is principally limb breakage and defcliation with occasional breakage of the main stem or uprooting. 5. Snubber wire arrangement for measurement of maximum deflecticn of tree stem is not feasible in a forested area composed of broadleaf trees and brush species where limb breakage is the principal form of damage. 3.2 RECOMMENDATIONS In future operations, where a detonation (preferably an air burst) is near or over forested areas, projects should be programed to obtain additional damage data on tree stands, and to secure needed peak dynamic pressure data for assessing the amcunt of attenuation. In that event duplicate gage installavion at all stations is advisable. In about two years, growth of vegetation on Uncle, Victor, and William Islands shculd ve sufficient in amount to provide areas for studying attenuaticn cf dynamic pressure. However, it will take many years before the growth will be sufficient to study tree damage. 45 SECRET ~- REETRICTED DATA