Erin Lavender

We just discovered a population of Oregon-Grape (Berberis aquifolium) growing in one of our high quality forested natural areas. The plants are in and around a power-line right-of-way that looks like it was cleared a few years back (maybe arriving in the area on clearing equipment or birds using the cleared area). Does anyone have experience working with this plant in MI? Specifically: how invasive does this plant tend to be in natural areas? best control techniques? most common dispersal technique (birds eating seeds, rhizomes, etc.)? Thanks for any insight!