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Response of citrus and other selected plant species to simulated HCL - acid rainMature valencia orange trees were sprayed with hydrochloric acid solutions (pH 7.8, 2.0, 1.0, and 0.5) in the field at the full bloom stage and at one month after fruit set. Potted valencia orange and dwarf citrus trees, four species of plants native to Merritt Island, and four agronomic species were exposed to various pH levels of simulated acid rain under controlled conditions. The acid rain was generated from dilutions of hydrochloric acid solutions or by passing water through an exhaust generated by burning solid rocket fuel. The plants were injured severely at pH levels below 1.0, but showed only slight injury at pH levels of 2.0 and above. Threshold injury levels were between 2.0 and 3.0 pH. The sensitivity of the different plant species to acid solutions was similar. Foliar injury symptoms were representative of acid rain including necrosis of young tissue, isolated necrotic spots or patches, and leaf abscission. Mature valencia orange trees sprayed with concentrations of 1.0 pH and 0.5 pH in the field had reduced fruit yields for two harvests after the treatment. All experimental trees were back to full productivity by the third harvest after treatment.
Document ID
Document Type
Conference Paper
Knott, W. M. (North Carolina State Univ. Raleigh, United States)
Heagle, A. S. (NASA John F. Kennedy Space Center Cocoa Beach, FL, United States)
Date Acquired
August 11, 2013
Publication Date
October 1, 1980
Publication Information
Publication: NASA. Washington The 1980 JANNAF Safety and Environ. Protect. Subcomm. Meeting
Subject Category
Distribution Limits
Work of the US Gov. Public Use Permitted.