Denise Robertson, a Park Ranger at Lake Kaweah and a new trail guide for
2001, was kind enough to pose with this strongly scented herb to give us
some dimension to the size of the mature plant. Thanks Denise. This
pungent herb grows in the path near the number 12 marker on the Swamp Trail.
Its groundcover-like growth habit changes dramatically in May, when the
square bloom stalks appear, growing to 24". It also looses its reddish
hue as the temperatures rise. Light blue to light lilac colored flowers
form whorls along the main stem, very similar to horehound. The dried flower
stalks often persist in the landscape through the winter.
Herbalist Eric Pollard said pennyroyal oil is a "highly toxic oil,
used mostly as a pesticide." It can kill "if less than a teaspoon
is ingested." Pennyroyal is used as a household ant and flea repellent.
causes internal bleeding and death if ingested as a tea or oil.
We will be attempting to eliminate this toxic non-native herb from the
to plants next