Common Toad Flax, Butter and Eggs
By Jorg Breuning
Linaria vulgaris ~ Photo by Jorg Breuning
Linaria vulgaris is listed by the USDA as noxious weed for several western states. I believe that this plant can be tolerated on un-irrigated green roofs in states where it is not considered noxious. This plant helps to prevent wind and water erosion on extensive green roofs. In a green roof environment it’s height is stunted to 1/4 normally sees on ground dwelling plants. Linaria vulgaris is also a great food source for honey bees and is not considered a noxious weed in states east of the Mississippi River.
Tell us what your thoughts are on the use of introduced or non-native plants on green roofs.