The tag on a Chicago resident’s new parkway tree clearly shows the species as “Aristocrat” pear, one of some two dozen cultivars of the invasive callery pear tree. (Courtesy of Eliza Rohr)

Just because a species is known to be invasive doesn’t mean it’s officially regulated as such. One Chicagoan learned that lesson the hard way.

A non-native subspecies of common reed is an invasive bully (l), crowding out its native counterpart in wetlands. (Credits: Caleb Slemmons, National Ecological Observatory Network, Bugwood.org (l); Rob Rutledge, Sault College, Bugwood.org)

For the last in our series on invasive species that can be mistaken for natives, here’s one of the trickiest: phragmites, also known as common reed.

Prairie (or field) thistle on the left, cutleaf teasel on the right. Which is native and which is invasive? (USGS Bee Inventory and Monitoring Lab; Patty Wetli / WTTW News)

In honor of National Invasive Species Awareness Week, we'll be posting daily "dupes" — invasives that can easily be confused with native species. 

Callery pear blossoms. (sharonshuping0 / Pixabay)

The candidates include well-known banes like garlic mustard and wild parsnip, but also a plant adored by landscapers and property owners: the Callery pear tree.

How local forest preserves are using fire to maintain the Chicago area's natural ecosystem, much like Native Americans did prior to European settlement.