DesMoinesRegister.com reports that DuPont Pioneer has confirmed that it made staffing changes at its Johnston headquarters. The company said the changes were "implemented to best position us for continued business growth," but declined to discuss them further. The names and bios of these six execs were removed from the company's website last week, reports the Register: Jeff Austin, vice president for business planning and communications; Susan Bunz, vice president for policy and outreach; Mike Gumina, vice president for production; Dan Jacobi, vice president for global supply chain; John Soper, vice president for crop genetics research; and Steve Waite, director of supply chain.