Origin:
Native to Eurasia, but introduced to the United States as an ornamental plant, and now is widespread in the northern states, from coast to coast.
Biology:
A perennial broadleaf weed, with a prostrate, creeping habit. Spread is by stolons, and reproduction is primarily by the vegetative parts, as bits of stems can root at the nodes. This makes it easily spread by mowers or in clippings and landscape materials. A common weed in turf or adjacent landscaped settings. It does not tolerate cultivation and is rare in crop settings. Grows best in cool, moist, shaded settings.
Identification:
The mature plant is prostrate and vine-like along the ground or turf. It remains green through the winter, although it may lose many leaves. In hot, dry weather the stems may become defoliated, but stolons will produce new leaves once cool weather returns. Leaves are small, round, and have scalloped, wavy margins and are sparsely hairy. Lower leaves are opposite, and those on the flowering sections of stems are alternate. Flowers are small, light blue or violet, and produce from late spring into early summer as single flowers in the leaf axils, on a short stalk.
Characteristicts Important to Control:
A perennial favoring moist, cool conditions. Tillering will control the plants in non-turf settings, but even 1 centimeter-long sections of stolons can produce new roots and plants.
