Rough hedge nettle is widespread in the area, and hedge nettles in general are easy to recognize. Though they don’t have the typical smell, hedge nettles are in the mint family! Mints are often hairy and smelly (like some rugged botanist-types that I know?!) and they have a tubular flower that usually is distinctly two-lipped. For the hedge nettles this is certainly the case. But the real giveaway for this family is that they have a square stem. Just roll it between your fingers to see what this means – all mint stems are distinctly four-sided (see the stem close-up below). There are other families that have square stems, but the many local species in the mint family (Lamiaceae) are by far the most common.
Stachys rigida is usually found in dry places—woods, shrublands, or grasslands. There are other hedge nettles (such as S. chamissonis, with its showy purple flowers) that prefer wetlands but our S. rigida is almost always on slopes, in gravel, clay or rocky soil. And, if you want to get technical, you should know that the Marin Flora lists Stachys rigida var. quercitorum as the local variety.
Flowers Of Marin 