Excerpts from Jim Conrad's
from the the May 13, 2012 Newsletter issued from the woods of the Loess Hill Region a few miles east of Natchez, Mississippi, USA
BRAZILIAN VERVAINS GALORE
Biking the countryside these days, again and again you pass great swaths of diffuse violaceousness, long roadsides of it, and entire fields that have been spared of bush-hogs and herbicides. You wonder how any one wildflower or weed could dominate so much of the landscape. You can see a tiny section of a roadside of it above. A close-up showing the dense flower heads is below:
A shot of the narrow leaves with serrated margins arising opposite one another on stems square in cross-section is shown below:
This is the Brazilian Vervain, VERBENA BRASILIENSIS, an annual or short-lived perennial, a member of the Verbena Family, the Verbenaceae. And it's truly from Brazil and other South American countries, though in much of the world's warmer parts it's becoming a serious invasive, pushing native species aside. In the US, so far Brazilian Vervain is limited to the Southeast and a bit of the West Coast.
Pollinators relish the Brazilian Vervain's flower nectar, on sunny mornings keeping the blossoms busy with activity. However, the fruits produced are regarded as of only minor importance to ground-foraging small birds and mammals. The species' value to wildlife is regarded so low that in the US its presence is prohibited on National Forest System Lands. In nearby Homochitto National Forest, however, it's common along gravel roads passing through the forest.