282 MALVACEAE (MALLOW FAMILY) 
segments again deeply cut or pinnatifid, very short-petioled. 
Flowers clustered at the ends of stem and branches and in the 
upper axils, often nearly two inches broad, pale rose-color or white, 
pink-veined, the central column of many styles and anthers nearly 
a half-inch in height; calyx with five short, triangular-ovate, very 
hairy lobes. Carpels fifteen to twenty, arranged in a circle, also 
densely hairy. 
Means of control 
Close cutting before the development of any seeds, repeating 
the treatment as the plants send up new shoots from the roots. 
BLADDER KETMIA 
Hibiscus Tridnum, L. 
Other English names: Flower-of-an-hour, Goodnight-at-noon, 
Shoofly Plant, Venice Mallow. 
Introduced. Annual. Propagates by seeds. 
Time of bloom: July to September. 
Seed-time: August to October. 
Range: Nova Scotia to Minnesota, south- 
ward to Florida. 
Habitat: Cultivated ground, roadsides, 
waste places. 
At one time this weed was much helped 
in its wide distribution by seedsmen who 
recommended it as an ornamental plant. 
But for that purpose its beauty is too 
evanescent, and in grain field and garden 
it has proved itself extremely obnoxious 
because of the long vitality of its seeds; 
ground once fouled continues to produce 
plants for years, as cultivation brings the 
dormant seeds to surface light and 
warmth. (Fig. 198.) 
Stems ten to twenty inches long, 
ie ane ea, branched from the base, slender, rather 
mia (Hibiscus Trionum). Weak and often reclining, covered with 
ch fine, bristly hairs. Leaves broadly heart- 
