sulphuring

/S AH1 L F ER0 IH0 NG/
verb
  1. 1

    To treat with sulfur, or a sulfur compound, especially to preserve or to counter agricultural pests.

Source: https://en.wiktionary.org/wiki/sulfur, https://en.wiktionary.org/wiki/sulphur, https://en.wiktionary.org/wiki/sulphuring