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Vilas County and Yellow Flag Iris

Non-native yellow flag iris (Iris pseudacorus) is becoming more common each year along northwoods lakes, streams and in wetlands.  Native blue flag iris (Iris virginica), also common in the northwoods, is much smaller and more delicate and does not present an environmental threat.  Yellow iris grows much taller and displays large, beautiful, bright yellow flowers.  It is very aggressive and capable of quickly overtaking native vegetation and altering shoreline/wetland habitat depended on by wildlife.
 
Does this sound something like purple loosestrife?  Look for yellow iris in the same areas.  But unlike the pretty purple flowered plants, there is no known biological agent we can use to control yellow iris.
 
Pulling young plants while their roots are relatively easy to remove is a better choice than waiting until plants are large with root masses the size of Volkswagen Beetles before trying to remove them, which would likely cause harmful and illegal shoreline disturbance (permits are needed before doing backhoe work, which is about what would be needed to extract the roots of a well established patch!). 
 
Yellow flag iris is classified as a noxious weed in many states.  It is proposed to be added to Wisconsin’s NR40 classification as a “Restricted” plant in the rule’s next update.