shepherd's purse
Family
BrassicaceaeScientific Name
Capsella bursa-pastoris
Synonyms (former Scientific Names):
Bursa gracilis
Capsella rubella
Bursa bursa-pastoris
Thlaspi bursa-pastoris
Bursa bursa-pastoris var. bifida
Habit
An annual, most commonly a winter annual, weed. Seedlings have egg-shaped cotyledons measuring 2-5 to 5 mm long and 1-2 mm wide. Upright stems reach heights of 80 cm with several branches.
Leaves
Leaves come in several different shapes, sizes, and types on Shepard's purse. They can have no slight toothing, to deeply toothed or lobed. This species also has leaves in two different arrangements; lower leaves are in a rosette, while upper leaves are alternate in arrangement. Leaves at the base can be 3 to 15 cm long and up to 4 cm wide and are clasping around the stem. Leaves are mostly hairless but lower sides may contain some hairs.
Identifying Characteristics
Wavy to deeply lobed leaves, white flowers, and triangular shaped pods with a notch on top are characteristic of this plant. Shepard's purse serves as a home to several fungi that attack cole crops i.e. turnip, and cabbage. This species is also host to a large number of viral diseases including: tobacco mosaic virus, beet yellow, cabbage black ring spot, cabbage ring necrosis, beet mosaic, beet ring spot, aster yellows, beet curly top, beet mosaic, cauliflower mosaic, cucumber mosaic, and radish mosaic.
Flower Seed Head
Flowers are made up of 4 petals and 4 sepals, are white in color, and measure 4-8 mm across and 2-4 mm long.
Seed Fruit
Triangle shaped pods appear on the elongating stem, which reaches its full length as the pods mature. Seed pod is 5-8 mm long and contains two chambers, each with 10 to 20 seeds.
Where Found
All over the United States and Canada this species is a major pest in row crops, cultivated fields, nursery, and vegetable crops as well as gardens. Shepard's purse is often found in waste areas and other disturbed soils
Growth Habit
upright and nonwoody
Thorns or Spines
not present
Approximate Flower Diameter
pencil
Dominant Flower Color
white
Flower Symmetry
not symmetrical
Leaf Hairs
Varies:
has hairs,
no hairs
Leaf Shape
Varies:
heart,
triangle
Leaf Arrangement
Varies:
alternate,
rosette
Leaf Margin
Varies:
entire,
lobed,
serrated
Leaf Structure
simple
Leaf Stalk
none
Stem Hairs
Varies:
has hairs,
no hairs
Stem Cross Section
round or oval
Milky Sap
not present
Root Structure
taproot
Life Cycle
winter annual
Ochrea
not present
Plant Type
Herb