ST. PAUL, Minn. — Manure deep-pits under swine barns in the Upper Midwest are getting full in this time of year, and concern over pit foaming is especially high. Pork producers should be vigilant.

Barbecue, in its many permutations of fire, smoke, and animal flesh, is more than just a timeless human tradition, key to global population growth and food preservation. It’s also a semi-unwritten ...