Hi, 

We are actually trialing this right now at our research center in Clarksville, but since it just started, we will have to wait a few years to see the results. We planted Golden Alexander (Zizia aurea), River oats (Chasmanthium latifolium), Golden ragwort (Packera aurea), and Eastern Woodland Sedge (Carex blanda) - to observe if any of those species would outcompete Japanese Stiltgrass. 

It depends on the invasive plants you are trying to control. If it is English Ivy, Houttuynia (Chamelon plant), or Bishop's weed, it would be best to ensure that those are fully removed and treated if need be before planting. 

There is a great article with plant lists in the new Maryland Native Plant Guide for the Piedmont Region, which you can download a PDF version for free or order a hard copy from the Maryland Native Plant Society. On pages 46-51, there are plant lists that you will find helpful. 

Ferns are a powerhouse, and a species I am familiar with, that can take over an area, is Eastern Haysented Fern (Dennstaedtia punctilobula). Generally, ferns prefer more moisture, but Haysected fern is pretty adaptable once established. Any of the species I listed in the Stiltgrass study could work as well. Another herbaceous plant that I have personally seen hold its own is Salvia lyrata. It can easily self-seed, and you can even run a mower over it at a high setting to cut it back if needed. The thick leaves at the ground level help shade out weed seed from germinating. 

Thicket-forming understory trees and shrubs may also be helpful, with some herbaceous plants underneath and around them until they can take off. There are lists in the guide for these as well. Planting small saplings as close as 2-3 feet apart, to mimic forest growth, is an economical way to plant an assortment of plants. It also proves to be less maintenance over time since the weeds don't have as much room to take hold. In time, some plants will outcompete others, but you will be establishing a native plant community rather than the invasives. You will still likely have to remove invasive plants from time to time, as seeds can travel on animal fur, hooves, or by droppings. 

Using a thick layer of arborist wood chips around the plantings is beneficial, too.  You can typically find them for free or for a small donation by searching for a chip drop (if you're not familiar with this).

Let us know if you have further questions. 

Emily