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Herb Robert

Geranium robertianum

Plant Description

Low-growing winter or spring annual or biennial with fern-like lacy green leaves that turn red as they mature or in high light exposure. Five-petalled pink flowers, seeds grow in elongated, pointed capsules. Stems are covered in fine, glandular hairs that exude a sticky, pungent-smelling substance giving the plant its nickname “stinky Bob.” Roots are shallow.

Plant Details

Life Forms
ODA Listing
Soil and Moisture Conditions
Suggested Actions
Shade Preference
Mature Height up to 10"
Distribution In Western Oregon and Washington.
Control Pull plants by grasping base firmly to avoid breaking brittle roots. Repeat for several years until seedbank has been depleted. If using herbicides, follow all label directions.
Disposal Methods Place plants that have set seed into a sealed bag for municipal waste disposal.
Reproduction and Spread Reproduces by seeds, which stick to and are moved by humans and other animals. Seeds can be ejected up to 20 feet from parent plant.
Introduced Introduced in Oregon in the 1980's. Originally from Europe, Asia, North Africa.
Look Alikes Shiny geranium and Erodium-genus (stork's bill) geraniums.
Impact Forms dense monocultures in forest understories, displacing native species, reducing diversity, and increasing landscape maintenance costs.
More Info
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