MILTON, Vt. — Maple syrup production has come a long way from metal buckets hung on trees, but even high-tech operations have had to rely on old-fashioned foot patrols to fix a common problem — leaks.

BRATTLEBORO — About 125 years ago the Vermont Phoenix, a Brattleboro newspaper, published an article by local sugar maker John Gale concerning the annual gathering of maple sap during the early spring ...