Sunn Hemp is definitely not Industrial Hemp.
Industrial hemp is Cannabis, where Sunn Hemp is Crotalaria, like you mentioned.
Every state has to set up a commision to set up rules and framework. The state's dept. of ag and university extension have to be involved.
Each state creates a pilot program from this process. It seems that each state can interpret what the pilot program should look like based on the 2014 Farm Bill allowing Industrial Hemp.
Most likely you are 1-2 years away from seeing anything significant in the ground.
North Carolina is way ahead of many states. Here's a brief snip of what is required:
"Rules for producing hemp have been approved and the commission has begun licensing growers to grow hemp under the rules. To grow industrial hemp in North Carolina, an individual must be a bona fide farmer in the state and provide tax information to show that.
Stewart says farmers must also agree to work with either North Carolina State University or North Carolina Agricultural and Technical State University to meet eleven research objectives established by statute in North Carolina.
Every farmer who grows hemp needs to address one or more of those objectives and turn over the information to the universities at the end of the year. We’re doing this so we can learn more about the crop,” Stewart says.
All planting of industrial hemp will be subject to sampling of THC, the psychoactive chemical found in marijuana. The North Carolina Department of Agriculture will conduct sampling of industrial hemp field and perform the sampling. By law, industrial hemp must have a THC level of 0.3 percent or less."
So, it will come down to how your state writes the rules.
NC State has a great site on this. Lots of great articles and links:
https://industrialhemp.ces.ncsu.edu/
And here is the application information page that a farmer wanting to sign up would go to, will answer a lot of your questions and maybe indicate what your state might mimic:
http://www.ncagr.gov/hemp/application.htm
The actual online application:
https://apps.ncagr.gov/AgRSysPortal/IndustrialHemp/
And the FAQ page for applying:
http://www.ncagr.gov/hemp/Application-FAQs.htm