Grassland fire effects on barbed wire

Abstract

Fire and its effects on rangeland plants, animals, soils, habitats, and watersheds has been studied extensively. Few studies have been devoted to fire effects on rangeland developments and no studies to our knowledge have been done on the effects of fire on barbed wire. From fire records and a known fence age at the Cross Timbers Experimental Range near Stillwater, Okla., we were able to determine the effect of varying fire frequencies on the breaking strength and zinc coating of traditional 2-point, double-stranded barbed wire. Samples from 4 burning frequency treatments, 8 locations each, of either 4 or 5-wire fencing were collected and stripped of their zinc coating for mass determination. Weight of zinc coating remaining on the wire was determined after being subjected to 0X, 1X, 2X, or 6X burn treatments over a 14-year period. A subset of 4 wires from 1X, 2X, and 6X burn treatments was tested for breaking strength. Photomicrographs and coating thickness measurements were also taken on samples from 1X, 2X, and 6X burn treatments. All tests were compared with unused wire of the same lot that had been in storage since fence installation. For the 6X burn treatment, breaking strength of 5,160 Newtons (N) and zinc coating thickness of 18.5 micrometer were equivalent to unused wire breaking strength and zinc coating (5,160 N, 16.6 micrometer respectively). It appeared that repeated fires did not adversely affect the corrosion resistance or breaking strength, and therefore service life of relatively new barbed wire fence.