Biological Control of Non-Native Invasive Annual Grass Species

Here is an experiment from RLS on Texas Rescue Grass, Bromus Cartharticus, which is an annual non-native invasive grass. It behaves similar to Cheatgrass, Bromus Tectorum. They both love bacterially dominated soil systems and are early successional plants that thrive in damaged or disturbed soils.

At first glance it appears that the untreated side is a healthier and more vibrant system. This is actually in a paddock that was split in two, seeded with perennial grasses, and then treated. What is hard to see in the picture is that the broadleaf weeds are the same on both sides, and that there are perennial seedlings germinating on the treated side where there are none on the untreated side. Instead, on the untreated side the Rescue Grass is vibrant and healthy. Of course no one wants to grow a stand of Rescue Grass, so reducing the cover of Rescue Grass was the intention of this experiment. 

With the use of Provide and Revive, tools for increasing microbial balance, we were able to shift the fungal bacterial ratio and increase fungal activity to selectively discourage the invasive annual Bromus grass and encourage desirable perennial grasses.

Professor David Johnson has been working on this same idea. Here is a slide from his presentation that illustrates how the fungal to bacterial ratio affects plant community. If you want your desired plants to thrive, you will need to make sure you have the ideal soil microbial community.