Crown Vetch is native to central and Eastern Europe, and the Caucus region of Asia. It was introduced to the US as early as the mid-1800s, and by the 1950s became widely planted as a groundcover, cover crop, and bank and slope stabilizer along roads and waterways. It is now found across the continental U.S. and in most counties of Minnesota. In Minnesota, it has been planted as a cover crop and used for soil stabilization, but these uses are in decline due to the invasive nature of the plant.
As I read it.
The state of Minnesota along with the every other state had encouraged the use of crown vetch for soil stabilization, manure crops, forage, and fodder for now approaching 200 years. The plant is now a naturalized participant in the ecology of the state.
Although Restricted Noxious Weeds are not required to be controlled or eradicated by law, landowners are strongly encouraged to manage these invasive plants on their properties in order to reduce spread into new areas.
As I read it.
Although the State of Minnesota nurtures thousands of acres of crown vetch along thousands of miles of roads criss-crossing the state, the state will make no effort to eradicate it from state owned lands to protect your property and prevent the seed from being deposited in your soils by birds and other vectors. However, by all means, we encourage you to do whatever you can to eradicate it on your property to prevent its further spread.
Here is an example of Minnesota state sponsored crown vetch.
I liken crown vetch (in a state where its use isn't prohibited) much like I do Gambusia in Kansas. Its an invasive non native that has become ubiquitous in state waters. Can it really be argued that moving some into your pond is compounding the problem? Hardy so. Gams are there to stay and they will fill all spaces they can both contributing to and taking from ancestral ecology and diversity.
Transportation of non-native species is a GD shame that we can squarely put on well meaning scientists who were short sighted and in many cases just plain wrong. A classic case of Will Roger's quote that was added to my signature a few days ago.
Especially where agriculture and state sponsored use is involved, controlling such an invasive is very complicated. The plant offers benefits to agriculture that are often exploited and its use will be continued. This species is naturalized and it is going to fill its place, if it hasn't done so already in the ecology of Minnesota and in every other state where it has been used and conditions support its naturalization. Its a done deal. We will not eradicate it and it will be controlled or inhibited only at the expense of individual land owners.
We need to pick our battles. Rather than focusing on established ... naturalized ... non-natives that cannot be controlled cost effectively without economic incentives, we need to focus on not creating new problems. An example, let's not encourage stocking Rusty crayfish in Nebraska ... (something that has happened on this forum with no opposition) ... which is a problem (I hope) that doesn't presently exist there.
Crown vetch grows on slopes with no topsoil and with no special preparation. Pretty remarkable and YES effective at stabilizing barren poor soils. Can it fail? Yes, when the site incurs substantial erosion before establishment, these ruts will continue to expand while they go unnoticed. But is it ineffective? Hardly, how can you blame it for erosion in soil where it isn't established? That doesn't make sense. The world is full of half-truths that are designed to fit some underlying agenda which is often personal (like one's purpose in life for which he/she is compensated). To be sure, I sympathize with those who think their agenda has some higher purpose. They want to fix a problem which they wish weren't there. Like them, I wish crown vetch weren't here at all but it will fill the spaces it can naturally all on its own from the naturalized population with natural vectors and there is nothing we can do about it.