Japanese stilt grass on the Run
by Maxine Kenny
Now that summer is only a memory we have time to reflect on our continuing struggle to combat garlic mustard, ailanthus and Japanese stilt grass – three of the most tenacious invasives on the Clinch Mountain Preserve’s 500-Year Forest. Fortunately for us we had the assistance of two young, energetic Eagle Scouts who pulled great patches of garlic mustard in the spring. One of the teenagers came back during the summer to help us stalk and destroy a great many ailanthus trees and saplings.
In an unexpected turn of events, nature itself may have set us on a path of biological elimination of the stilt grass that has swept across our lower acreage and along pathways that lead into our 500-Year Forest on the upper slopes of the Clinch Mountain. In early July a forester friend, Russ Richardson, told us about a fungus called Bipolaris that he thought was killing stilt grass on his West Virginia farm. He sent pictures to us of stilt grass that had brown lesions on its leaves and shared an academic paper regarding the phenomenon written by a biologist at Indiana University. Later in July, during a hiking trip to the Pinnacle Natural Area Preserve in southwest Virginia, we saw stilt grass along the hiking trails that appeared to be afflicted with the same brown lesions. Subsequently, that sample was confirmed as infected by Bipolaris fungus.
Soon after we saw what we believed to be Bipolaris lesions on the stilt grass along our own driveway. We sent it off to be analyzed and it too was confirmed as Bipolaris. We checked back with Russ in West Virginia to discuss the infestation on our property and he said that the fungus spreads in much the same way as stilt grass itself – that is, it rides along pathways traveled by both humans and animals – so he wasn’t surprised that after we waded through infected stilt grass at the Pinnacle that it had hitchhiked back home with us on our trouser legs. He also told us that much of the thriving stilt grass that he observed on his property last year was now reduced to a dead, dry thatch! Wouldn’t it be wonderful if nature could rid our fields and forests of stilt grass?