Yesterday my neighbor showed up with a pickup load of firewood, which he was dumping off as an informal exchange for some work. Henry doesn't do chainsaw, ostensibly because his first wife told him not to, although as far as I know his current wife doesn't care. He also borrowed my splitter to process his holdings, including the portion I had sectioned. So I didn't refuse the donation.
Anyhow, I was scouting out where to build my woodshed, which might involve clearing some vegetation and even cutting into the hillside behind the house. I had a small stand of some sort of attractive shrub which I was thinking I'd regret removing, but Henry told me they were Russian olives, which are, as it turns out, an invasive alien species that all good people should destroy. I checked it out on your Intertubes and sure enough, he's right. So I broke out my trusty Stihl Farm Boss™ and terminated them with extreme prejudice.
By the way, Henry has also been volunteering on a crew to extirpate another invasive species called mile-a-minute weed from the banks of the Shetucket,* just a half mile from here. The plant is named, of course, for the rate at which it spreads.
The bad news is, this is hopeless. If you Google Russian olive, you will not only find stern orders to destroy it, you will also find nurseries selling it with lavish praise for its beauty and hardiness. Evidently this is legal, though evil. Most landowners will probably never even learn that it's a harmful invader. If they do, they are unlikely to possess the equipment and capability to remove it, and many won't even have the inclination. As for the mile-a-minute weed, those volunteers will just have to keep going back several times every year and yanking it out, but it is highly unlikely they will ever eradicate it.
BTW, I learned from William Cronon's book Changes in the Land that many of our most familiar weeds -- dandelions, plantains, burdocks -- are in fact European invaders, whose seeds arrived as contaminants in animal feed, apparently. Perhaps they are not so harmful, but humans just keep mixing up the flora and fauna of the continents and oceans, to nobody ever knows what result, but it's usually bad.
Oh well, too late.
*Wickipedia:"The river flows through an especially unspoiled rural section of southern New England, despite the historical prevalence of industry in the surrounding region. Parts of the rivers have been designated by the federal government as the Quinebaug and Shetucket Rivers Valley National Heritage Corridor. The National Park Service describes the river valley as the "last green valley" in the Boston-to-Washington megalopolis. In nighttime satellite photos, the valley appears distinctively dark amidst the lights of the surrounding urban and suburban regions." Just so you know, that's where we are.