By Jeff Plakke, Matthaei-Nichols Field Services Manager
About this time of year people start asking, and the answer is still no, thankfully: we do not have the exotic giant hogweed growing on our properties. What people often report is in fact the native cow parsnip which looks quite similar. The obvious distinction, if you saw the plants side by side, is that giant hogweed grows much, much larger. Cow parsnip can get up to 7 feet tall, giant hogweed up to 14 feet tall. Leaves of cow parsnip can get almost 3 feet wide, giant hogweed leaves can get 5 feet wide. Giant hogweed has been in the news a lot in recent years and is intriguing and alarming because it is so big and the sap is very toxic. So far it is not widely spread in MI. It’s in three counties: Ingham County (Lansing), Gogebic County (borders Wisconsin in the upper peninsula) and Berrien County (southwest lower Michigan – St. Joseph).
You can find cow parsnip growing in a number spots at Matthaei including along the trails in the Fleming Creek floodplain, and along the edge of Willow Pond. At the Arb there are colonies of cow parsnip growing along the River Rd. (Nichols Dr.) and in the wetland boardwalk area. A large patch near School Girl’s Glen bridge has been reported to us numerous times over the past few years. It’s good that people are paying attention to the plants!