field madder
Family
RubiaceaeScientific Name
Sherardia arvensis
Other Common Names:
blue fieldmadder
Leaves
Whorled with 4 to 6 leaves at each node. Leaves are lanceolate to elliptic in outline, approximately 5 to 15 mm long and 2 to 4 mm wide. Leaves taper to a distinct tip and are hairy.
Identifying Characteristics
A prostrate winter annual with whorled leaves, square stems, and pink to purple flowers. Field madder is primarily a weed of turfgrass, lawns, and occasionally winter small grains. The square stems, whorled leaves, and pink to purple flowers are all characteristics that help in the identification of field madder. Field madder is often mistaken for either Smooth Bedstraw (Galium mollugo) or catchweed bedstraw (Galium aparine). However, the leaves of the bedstraws are generally larger and occur in whorls of 6 to 8 unlike field madder. Additionally, the leaves of field madder are more lanceolate and have much more of a distinct point than those of the bedstraw species.
Flower Seed Head
Stems: May be either prostrate along the ground (typical), erect, or prostrate with some tips ascending. Stems are square in cross-section and also hairy.
Flowers: Occur in clusters at the ends of the stems. Individual flowers are 3 to 4 mm in length and pink to purple in color.
Where Found
This weed is distributed throughout the southern United States.
Growth Habit
upright and nonwoody
Thorns or Spines
not present
Approximate Flower Diameter
pencil
Dominant Flower Color
Varies:
blue,
purple,
pink
Flower Symmetry
bilateral symmetry
Leaf Hairs
has hairs
Leaf Shape
lance
Leaf Arrangement
whorled
Leaf Margin
serrated
Leaf Structure
simple
Leaf Stalk
none
Stem Hairs
has hairs
Stem Cross Section
square or multi-edged
Milky Sap
not present
Life Cycle
winter annual
Ochrea
not present
Plant Type
Herb