Chances are if you have driven along any country road in Illinois, you have seen a tall plant with a spiky silvery thistle-like flower head swaying in the wind. What you may not know is that this plant hides a sinister side. Cutleaf teasel (Dipsacus laciniatus) and its relative the Common teasel (Dipsacus fullonum) are prairie “bullies” and have been slowly taking over our high-quality agricultural landscapes.  

Brown Marmorated Stink Bug  

They are crawling on my windows, walls, and houseplants newly rescued from the lower night temperatures of the fall and creeping me out. They could be hanging out on your dishes, doing a balancing act on your toothbrush, resting in your clothing or hair, or be a rather interesting ornament on your Christmas tree. 

Giant hogweed

Wild parsnip often makes headlines because of its negative effects on naïve gardeners and hikers. Wild parsnip along with giant hogweed and poison hemlock are types of carrots gone bad.

If you didn’t know, we are cultivating invasive trees in backyards and urban settings. Tree-of-heaven (Ailanthus altissima) and Amur corktree (Phellodendron amurense) are outcompeting surrounding plants and invading natural areas contributing to the loss of native species in Illinois. 

Callery Pear on forest edge - Photo by Chris Evans, University of Illinois Extension

Do you see those beautiful white flowering trees lining the streets and backyards? These delicate white blossoms, made brighter by the months of winter endured, are actually an environmental hazard to the Illinois wilds. Callery Pear season is upon us.