I often read about citrus varieties from other countries (ex. Japan) that aren't available in the US. Is it safe to assume that these are effectively impossible to obtain, or is there some legal path to import that doesn't require a quarantine program? And that is assuming the source countries are even willing to export them. I know citrus growing states have their own rules, are there also federal rules?
EDIT - I think I found my answer. Federal regulation only allows citrus imports under special permit, for the three below purposes, for 1-3 years.
Developmental purposes. The evaluation, monitoring, or verification of plant material for plant health risks and/or the adaptability of the material for certain uses or environments.
Experimental purposes. Scientific testing which utilizes collected data and employs analytical processes under controlled conditions to create qualitative or quantitative results.
Therapeutic purposes. The application of specific scientific processes designed to eliminate, isolate, or remove potential plant pests or diseases.