Introducing a new CCMJ feature, where we highlight one popular (or unpopular) weed from the classic book Weeds of the Cranberry Marsh: Jed Colquhoun, Teryl Roper, Josh Sulman. ©2009 by the Wisconsin Cranberry Board, Inc.

This week, Northern St. Johnswort. Check the photos in the book to distinguish from Creeping St. Johnswort, Shrubby St. Johnswort, Larger Canadian St. Johnswort, and Common St. Johnswort.

Hypericum boreale: Northern St. Johnswort

life cycle / growth habit: perennial herb to 1 ft. tall

root: tufts of slender, white roots from the nodes of the creeping stems

stem: stems creeping, whitish to often bright red, sometimes much branched

leaf: opposite, oval, untoothed, to 1/2 in. long, with 3–5 red veins from the base

fower: fowers small and inconspicuous, yellow-orange, with 5 petals; blooms July–September

fruit/seed: pointed red pod, 1/4 in. long, enclosed by the green sepals, seeds several, tiny

This article was posted in Cranberry and tagged Allison Jonjak, Cranberries, Jed Colquhoun, Josh Sulman, Northern St. Johnswort, Weed of the Week.