First discovered in Switzerland around 30 years ago, yellow nutsedge (Cyperus esculentus) is a non-indigenous plant that has spread exponentially at the expense of local crops. Classified among the neophytic invasive species, it has been placed on the Blacklist.
Present on all continents, yellow nutsedge is an annual species adapted to temperate climates. Its spread in Switzerland represents a threat to agriculture, inflicting sizeable economic losses in numerous crops.
This species tolerates cold temperatures and is frost-resistant thanks to its numerous tubers present in the soil. The plant forms underground rhizomes which develop tubers on their ends during the summer. A large percentage of these tubers germinate the following year when environmental conditions are right. The rest remain in a dormant state in the soil.
Classic graminicides (grassy-weed killers) and the majority of other herbicides are not effective in controlling this member of the Cyperaceae family. Only a combination of different approaches allows for the long-term control of this species.
The working group coordination nationale Souchet comestible (‘Yellow Nutsedge National Coordinating Committee’), which brings together representatives from the authorities (Cantons, FOAG, FOEN), research (Agroscope, HAFL, FiBL), extension services (Agridea, specialised services, enterprises and others) and agricultural practice (sectoral branches, farmers, agricultural contractors) has been set up with the aim of coordinating control throughout the whole of Switzerland.