Integrated Pest Management
Hoary Cress
Cadaria draba
Hoary cress flowers (Mark Schwarzlander, University of Idaho, Bugwood.org)
Hoary cress seedling (K. George Beck and James Sebastian, Colorado State University, Bugwood.org)
Hoary cress fruits (Joseph DiTomaso, University of California - Davis, Bugwood.org)
Description
- plant with upright growth up to 2 feet in height and oblong to lance-shaped leaves
- stems are slightly hairy and leaves are bluish-green in color and are directly attached to stems (no petiole)
- white flowers are small and grow in dense clusters
- seeds are produced inside inflated, heart-shaped pods
- plants produce rhizomes
Location
- commonly grows in planting beds
Life Cycle
- herbaceous perennial with early spring growth
- rosettes and flowers produced by late spring
- seeds mature by mid-summer; plants can flower and produce seed again by late summer
- fall frost will kill the aboveground portion of the plant
IPM Recommendations
- Hand-pull plants in planting beds prior to seed maturation.
- Effective control must target both aboveground and underground plant structures; manually remove underground structures to prevent re-sprouting.
- Shallow tillage or hoeing will control young plants in planting beds. Do not till established plants; root fragments will produce new plants.
- Apply an appropriate post-emergent herbicide directly to target weeds.