We travel in the Western states a lot and never had a HOUSE plant issue. When asked I always say we have some house plants.
Once we had tomatoes and green onions (tops only) taken coming into the US from Canada. That regulation came in to the US border agents that morning. Had a good discussion with the agent, I ate one tomato and we cut off the onion tops and gave them to him for disposal.
Firewood may be prohibited across state lines and is to be expected. At the Port Angeles ferry to Canada I asked what we could do with the firewood. He pointed to a truck and said when it's full the employees bid on it and the money is used to help local children. I was happy to donate.