Japanese Stiltgrass (IMAGE) Penn State Caption Japanese stiltgrass, or Microstegium, is one of the most common invasive plants in Pennsylvania, and is often seen around shale gas well pads and access roads. It establishes dense stands in forest understory and chokes out native vegetation. Credit Mortensen's Lab, Penn State Usage Restrictions Non commercial use only License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.