Yes, this twine will work. Make sure to use Sturdy Stakes and secure tightly to the supports.
The twine recently passed all Proposition 65 testing and was not found to be in violation of any chemicals on the list.
Thank you for your question. The twine will biodegrade over time, but you should easily be able to get one full season out of the twine when using for typical garden plant support.
I don't know either but it doesn't cut into the plant stems and grips to the bamboo sticks supporting my plants.