Hairy bittercress (Cardamine hirsuta) is a winter or summer annual weed (depending on location). Stems can be 3-9 inches long, and the leaves are mostly on the lower portion of the stem in a basal rosette. Leaf margins are deeply lobed. Leaves at the base of the plant are larger than the leaves at the top of the plant. Small hairs can be found at the base of the leaf as well as on the top of the leaf surface. Flowers are small and white. Small round fruits (capsules) develop at the ends of each branch.

Winter annual broadleaf weeds germinate in the fall or winter and grow during any warm weather, which may occur in the winter, but otherwise remain somewhat dormant during the winter. They resume growth and produce seed in the spring and die as temperatures increase in late spring and early summer. They quickly invade thin turf areas especially where there is good soil moisture. Shade may also encourage growth. Many have a prostrate growth habit and are not affected by mowing. A dense, vigorous turf is the best way to reduce the encroachment of winter annual weeds. First, select adapted turfgrass cultivars for your area and then properly fertilize, mow, and water to encourage dense growth.

• GROWTH SEASON / LIFE CYCLE
  • summer annual or winter annual weed
• GROWTH HABIT
  • upright or rosette
    Figure 1, Figure 2, Figure 3, Figure 4, Figure 5, Figure 6, Figure 7, Figure 8
• LEAFLET NUMBER
  • 2 - 4 pairs of leaflets arranged alternately
• LEAF MARGIN
  • shallowly toothed or with a few lobes
• LEAF HAIRS
  • upper/lower surface
• LEAF / LEAFLET SHAPE
  • heart / kidney / spade
    Figure 9
• LEAF WIDTH
  • <¹⁄₂ - 1 inch
• LEAF VENATION
  • pinnate
• LEAF ARRANGEMENT
  • alternate
    Figure 10
• ROOT TYPE
  • fibrous
    Figure 11
• FLOWER COLOR
  • white
    Figure 12, Figure 13, Figure 14, Figure 15

Figure 1. Hairy bittercress growth habit.

×

Figure 1. Hairy bittercress growth habit.

Print Image

Figure 2. Hairy bittercress growth habit.

×

Figure 2. Hairy bittercress growth habit.

Print Image

Figure 3. Hairy bittercress growth habit.

×

Figure 3. Hairy bittercress growth habit.

Print Image

Figure 4. Hairy bittercress growth habit.

×

Figure 4. Hairy bittercress growth habit.

Print Image

Figure 5. Hairy bittercress growth habit.

×

Figure 5. Hairy bittercress growth habit.

Print Image

Figure 6. Hairy bittercress growth habit.

×

Figure 6. Hairy bittercress growth habit.

Print Image

Figure 7. Hairy bittercress growth habit.

×

Figure 7. Hairy bittercress growth habit.

Print Image

Figure 8. Hairy bittercress growth habit.

×

Figure 8. Hairy bittercress growth habit.

Print Image

Figure 9. Hairy bittercress leaflet shape.

×

Figure 9. Hairy bittercress leaflet shape.

Print Image

Figure 10. Hairy bittercress leaf arrangement.

×

Figure 10. Hairy bittercress leaf arrangement.

Print Image

Figure 11. Hairy bittercress root type.

×

Figure 11. Hairy bittercress root type.

Print Image

Figure 12. Hairy bittercress flower color.

×

Figure 12. Hairy bittercress flower color.

Print Image

Figure 13. Hairy bittercress flower color.

×

Figure 13. Hairy bittercress flower color.

Print Image

Figure 14. Hairy bittercress flower color.

×

Figure 14. Hairy bittercress flower color.

Print Image

Figure 15. Hairy bittercress flower color.

×

Figure 15. Hairy bittercress flower color.

Print Image