Goats.

You may or may not know, but there are two goats in use somewhere along the D&L trail to keep invasive species to a minimum.

I just read an article about how elsewhere, some rail trail system is employing 50 goats to get rid of an invasive species of plant that has outnumbered the native plants.

I also just read that goats will readily eat autumn olive.

What's the worst that can happen with 50 goats running around at Trex