Narrowleaf Bittercress
Management Prioritization
Identification
Common Names: Narrowleaf Bittercress, Narrow-leaved Bittercress, Bushy rock-cress
Scientific name: Cardamine impatiens L.
Related species: C. pectinata Pall. Ex DC. (sometimes listed as a subspecies of C. impatiens)
Legal Status: Prohibited - Control
Efforts must be made to prevent seed maturation and dispersal of plants into new areas. Additionally, no transportation, propagation, or sale of these plants is allowed. Failure to comply may result in enforcement action by the county or local municipality. Minnesota Noxious Weed Law .
Background
Rapidly invading forested areas along rivers in eastern Minnesota, narrowleaf bittercress is raising concerns about its invasive potential. It is not known how narrowleaf bittercress was introduced to North America from Eurasia. It was first reported in the US in New England in 1916. The first report in Minnesota was in 2008. By 2009, multiple discrete infestations were reported in several counties.
Narrowleaf bittercress is an annual or biennial forb that has a height of 6- 31 inches.
Seedling and Rosette
First year plants form a rosette and rarely flower. More commonly, the basal leaves of the rosette die over winter and the plant bolts and flowers the second year on an erect stem.
Narrowleaf bittercress seedling
Narrowleaf bittercress basal rosette
Leaf
The rosettes have 3- 11 leaflets with rounded lobes. In contrast, bolted plants have 6- 20 sharply toothed leaflets.
Top: Rosette leaf Bottom: Bolted plant leaf
Flower
Multiple small flowers with 4 white petals produce slender seedpods (siliques) from May to September.
Narrowleaf bittercress flower Photo: Leslie J. Mehrhoff, University of Connecticut, Bugwood.
Seed
Narrowleaf bittercress reproduces exclusively by seed and a single plant can produce up to 5,500 seeds.
Narrowleaf bittercress siliques
Narrowleaf bittercress siliques Leslie J. Mehrhoff, University of Connecticut, Bugwood.org licensed under a Creative Commons Attribution 3.0 License .
Distribution
Predicted Distribution
- Point data collected from EDDMapS; not all locations in the state have been recorded, but points on distribution map have been reported and verified.
- Distribution model takes location data and environmental factors into account to create a prediction of current distribution
Management Prioritization
Influenced by:
- distribution models
- actual reports
- economic benefits
- land cover
- conservation features
- trails
High priority areas surround areas of high density to prevent further large infestations and loss of biodiversity.
Infestation Example
01 / 03
1
General Infested Area
Seedling, rosettes and bolted plants dominate the forest understory. Management here is involved.
2
Leading Edge
Sparse populations in the transition from infested areas to un-infested areas.
Management is involved but can prevent further spread or large establishment of stands.
3
Isolated Population
Location far from other known populations.
Management here is efficient and cost effective.
Lifecycle: Treatment Timing
Funding for this project was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR). The Trust Fund is a permanent fund constitutionally established by the citizens of Minnesota to assist in the protection, conservation, preservation, and enhancement of the state’s air, water, land, fish, wildlife, and other natural resources. Currently 40% of net Minnesota State Lottery proceeds are dedicated to growing the Trust Fund and ensuring future benefits for Minnesota’s environment and natural resources.
