by BERNARD TOBIN
It was supposed to be just another day scouting fields for certified professional crop consultant Mervyn Erb.
On this bright, sunny June afternoon, Erb travelled just east of Exeter to inspect a cornfield for Jack, one of his grower customers. The cornfield had a large population of tufted vetch, and Erb wanted to see whether the herbicide he had prescribed to take out the perennial legume was doing the job.