Terrestrial Invasives

Genista monspessulana

Genista monspessulanaMontpellier broom/ French Broom

Common Name 
Montpellier broom/ French Broom
Legal Status 
Target Species
NEMBA 1a
Description

A 1-3m high shrub native to Europe with unarmed, slender, erect, very leafy, green branches; young branches are ridged and hairy. Short racemes of 3-9 flowers positioned at the tips of lateral branches. Flowers are pea-like, bright yellow, up to 13mm long; flowering from August-January. Seed pods are rusty brown, covered with silky hairs, usually with 5-8 seeds per pod.

Close up of the leaves
Immature fruit
Where does this species come from? 
The invasive Genista monspessulana is native to Europe.
Why is it a problem? 
French broom can invade a wide range of habitats including roadsides, fields, logged areas, bluffs and coastal areas. Similar to Scotch broom, French broom can fix nitrogen through its association with soil fungi and thereby disrupt low-nutrient ecosystems. French broom can also interfere with re-forestation and can aid the spread of wildfires. High seed production and long-lived seeds make eradication of established populations very difficult.

Means of reproduction? 
French broom is a woody, tap-rooted shrub that reproduces by seed. It doesn't spread vegetatively from its roots, but plants can survive cutting and tend to re-sprout from the crown when cut or burned. Seeds are produced in hard, dry legume pods that burst open when mature. Seeds are generally dispersed close to the parent plant unless soil is moved through erosion, flooding or other means. Similar to other broom species, French broom seeds are hard and long-lived. Plants can produce over 8000 seeds a year.