The use of natural gas heating to prevent spring freeze damage in the appalachian fruit region of the United States

Abstract

A natural gas heating system covering 50 acres of apples in Hancock, Maryland, was used to prevent freeze damage during the night of April 19–20, 1969. Simple wind proof burners with cones are installed 40/acre. Each heater's B.T.U. output ranges from about 38,000/h at about 5 p.s.i. to 180,000/h at 20 p.s.i. This provides a maximum B.T.U./acre of 7 million. By starting at 5 p.s.i. at 23.30 E.S.T., increasing to 10 p.s.i. at 02.30 E.S.T. and 15 p.s.i. at 04.00 E.S.T., a heating effect of 4°F or more was maintained in the 5–15 ft. fruit zone through the night. Minimum in the test area at the 5-ft. level was 31°F compared with the check 5-ft. level minimum of 23°F.