Two Common Invasive Species

Unfortunately there are a bunch of non-native invasive plant species that are impacting our natural areas – two of the more common ones are garlic mustard (Alliaria petiolata) and glossy buckthorn (Frangula alnus).  I recently gave a talk about invasives management at the Ohio Invasive Plant Council Annual Meeting – here are a few pages from my notebook that I scanned for the presentation and the take home message for each.

This is a sketch of garlic mustard that has been cut off near the ground and left in the woods (a technique that is approved for management of large nasty monocultures of garlic mustard).  I think of this as a reduction not a control – the cut plants will often times have enough stored energy to re-flower and produce seed.  Similarly the cut stalks have enough energy to mature the young seed pods (seliques) and produce seed.  Take home message is that it is always best to pull these plants by their roods and get them out of your woods!

This watercolor sketch is of glossy buckthorn in a wetland – once these things grow too large to hand-pull the best management becomes cut and treat (with herbicide).  I tried to illustrate that once the plant is cut only a small window (5 minutes or so) exists in which an herbicide treatment is effective.  Oftentimes people call and want to know how to kill buckthorn and/or other woody invasive species on their own property – the vast majority of them are doing everything right except that they are treating with herbicide beyond the 5 minute window.